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Hydraulic Report 3APPENDIX A -Project Maps Vicinity Map SCS Soils Map Regional Topography FEMA 100-Year Flood Plain Map SHILLINGS CONNOLLY, INC. 5 Yelm Property Development LLC Hytlrology Report _I ________ t~ Z 300 1 i i xx Ii i i; • ° n e3oo 9 ;; -o D li i' , aoP.e,~,.,9 oeu~l,Ee A=, al~e,~~.,aE,la,Eo i i i i i ~ ~ ~ N ~ i i i ~ i _____y_________________i______ __________~ i i ~ ~ i___________I .___. \1,'V~... ~,. _~ ty _ .. 1. __ ,~ : ~~ui_.._.~ a .,. ~ , T77N _ .~,,, E , de ~ ~~ W I I,.. - ~ p ~ (V s. p m e . x.~ a i _ ~i CL~ 9 p C ___y[~~ _ ____'i.]E ~$d P_F___ ~_____.. 5 3A~i • 1I 0-29 I 1 2mxEr. Gxrx F e ,v..~c.. E_ A',. 12_ a ~ VICINITY MAP la~ZOne _ ~_~ ~ `... f I ~, .,..-. ~..- \.. I • 4 ..~ .~ -..... - ~ - -- • ~ y ~ -- e~~m ~ ~" rF - µ ~'~~~; f p o. ~ ~ ~ ~ '~ ~t~ 1 Flumo I .. f ; ~ .: ~ ~ . o ~ ~ J. ~ , ~~. ~ ~ ~~ ~ _ ~ {51Q/J \FO.. gg ~ ~ , I • • ~l l/ 11~ tl ~ 1¢. / ~ ~ ~ I V_.. .~ iy,. ~ .l S~TE~ r \ ~~,~I ~ ._ • , 1215 ,--- ;"' ~~ .Y \ K .\ ~ 343 °'.,. , 7 • ~ ` l r' 329 - - n • , • \ ~'~ ~ \ ~ ~ ,a, ~ p i f "~ .d . . 0 0.1 0.2 0.3 0.9 0.5 km 0.09 0.18 0.27 0.36 0.45 mi Map center is UTM 10 528969E 5200181N (WGSS4/NAD83) McKenna quadrangle Projection is UTM Zone 10 NAD83 Datum G ~m M=18 G=0.278 c mE 6 m 6 Ti E`oq OOE W o eE - f o Q `~ a 2 ¢ } w~ F Z i us~~'^ z 6uf w ~ yoBSF ~ - 6 ~ ~ ~ T W f SEO_ ~~ a ~ [.~Z d Z e _~EELL 4 co O~~K a ~ ~ ~4Yw a w ~8y~g SELL -°caE n~mv~ X30' 31VtlOdtlO~ avotl NOITIIM _r H ' pVOtl M31A ~1N dtlOtl APPENDIX B -Conveyance Calculations Water Quality Calculations Drywell Sizing Computer Calculations SKILLINGS CONNOLLY, INC. 6 Velm Property Development LLC Hytlmlogy Report yo u EC ~ `"~ q G ab - V u r w o ~ ~ i was ~n c ~ E°m° v~ o ~ _ I ~ a DP o a -~ ~_ ~ o ' L' m „ ++ C ~E °i ~ N F ¢m C J O ~ n'Y' L O LL£~ 3 c~e ~ rvv ai m°~-' ~ O O Y (Q O C 'o a` ~ ~ ;..zit _ - ~. w o~ m s,{ 'a i ,~ ~ ~ ~ _ a >a o ,.r ~~ w i 3 0< ~ ~! ua - -4 c '~ J ~ n ~ ~ c ~ EEz LL s i a LL ,. s dR o e, ~ ,~:, - ~_ _- 9 ~ s 7+ z° ~ E ,~ I ~ E pxn a ~~ {* _~ h i sX%,, & ego n r d z F. N~~ d9-` f n ate.. s~.;:r~t ~ ~c?a a^~ -[s` ~ - _~ STORHWATEA MANAGEMENT MANUAL FOA THE PUGET SOUND BASIN Figure III-3.17 Roof pownapout System CB ~/~r Trench) _-_~,. Roo 1 -Trench y~ ~_-- CB ~J Possible Alignments Raof drain PLAN VIEW ~ Nat to Scale Observation Well / 6" Perforated Pipe . ~ _______ ~,~1 1 1 I _ 1 _ _-_-_____. Sump wl `~ Infiltration Trench ~-J solid lid PROFILE VIEW nts OVerfIOV Observation Well Splash hloc:< A Sheet Cover Material Roof Drain r min .---_-- . L.wi ~ 1' mm. I G .I 1' min. i Fine t' min~R ~~~, _ __ i mash I 5' min. L.vI screen CB Sump with A 6" Perforated Pipe Solid Lid ICPEP single wall acceptable) varies 10' min. Observation Well Iw/metal cap & lock) Compact Backfill 4"-6" PVC Pipe 4 .~~ _ bw+~ ~ 6" Perforated Pipe 14" acceptable Iperforatedl for roof downspout systems) Wrap Trench Washed rack'/." - 1Y" Entirely With Filter Fabric • ~ SECTION A-A ~~ I Nat to Scala ~~ MGS FLOOD PROJECT REPORT Program Version: 2.27 Run Dale: 09/06/2006 3:44 PM •*+xx*++*******x**+*****xx**+********x*xx*:*+++*t**+***x***++:****+*r:**x:*xx****** Input Fi 1e Name: 06099 A.f1d Project Name The Hutch Analysis Title: Basin 'A' -~ Comments Extended Ti meseries Selected Climatic Aegion Number: 11 Full Period of Record Available used for Routing Precipitation Station 960040 Puget East 40 in NAP 10/01/1939-10/01/209"1 Evaporation Station 961040 Puget East 40 in NAP Evaporation Scale Factor 0.']50 HSPF Parameter Region Number: 1 HSPF Parameter Region Name USGS Default ********* Default HSPF Parameters Used (Not Modified by User) *************** Page 2 ********* Watershed Definition ********** Number of Subbasins: 1 *** ***** Subbasin Number: 1 ********* * *Tributary to Node: 1 **=Bypass to Node None Area (AC res) -- ----developed - ---- Predeveloped To Node Bypass Node Include GW Till Forest 0. 000 0 .000 0 .000 No Till Pasture 0. 000 0 .000 0 .000 No Till Grass 0. 000 0 .000 0 .000 No Out wash Forest 0. 000 0 .000 0 .000 No Ou[wash Pasture 8. 960 0 .000 0 .000 No Outwash Grass 0. 000 3 .250 0 .000 No Wetland 0 .000 0 .000 0 .000 No Impervious 0. 000 5 .']10 0 .000 HNHBABIN TOTAL 8 .960 8 .960 0 .000 *** Subbasin Connection Summary *** Subbasin 1 ----- > Node 1 *** By-Pass Area Connection Summary =** No By-Passed Axeas in Watershed Pond Inflow Node 1 Pond Outflow Node: 99 Page 10 ************* Flow Frequency Data for Selected Recurrence Intervals ************* Subbasin 1 Runoff Predevelopment* Tr (Years) Flow (cf s) 6-Month 0.001 2-Year 0.003 5-Year 0.005 10-Year 0.024 25-Year 0.048 50-Year 0.149 100-Year 0.165 200-Year 0.232 * Recurrence Interval Computed Using Subbasin 1 Aunoff Postdevelopment* Fl ow(cf s) 1.111 1.965 1.910 2.246 2.'125 3.124 3.561 9.042 Generalized Extreme Value Distribution Page 15 ****************** Water Quality Facility Data *************** H as is Wet Pond Volume (91% Exceedance): 24832. cu-ft Computed Large Wet Pond Volume, 1.5*Basic Volume: 39298. cu-ft 15-Minute Timestep, Water Quality Treatment Design Discharge Discharge Rates Computed for Node: 1 ~ On-line Design Discharge Rate (91% Exceedance) 0.99 c£s ~ YIlEA7/~7E./ /' Of£-line Design Discharge Rate (91% Exceedance): 0.55 cfs FGV6~JC&ava A') MGS FLOOD PROJECT REPORT Program Version: 2.27 Run Oate: 09/06/2006 3:58 PM ***x************+*****+*+***x**+++***xx*****+*x*x**+****:***************++*****xr.* Input File Name: 06099 B.f1d Project Name The Hutch Analysis Title: Basin 'B' ~- Comments Extended Ti me series Selected Climatic Region Number: 11 Full Period of Record Available used for Rou Cing Precipitation Station 960040 Puget East 40 in NAP 10/01/1939-10/01/2099 Evaporation Station 961040 Puget East 40 in NAP Evaporation Scale Factor 0.'150 HSPF Parameter Region Number: 1 HSPF Parameter Region Name USGS Default ********* Default HSPF Parameters Used (Not Modified by User) *************** Page 2 *****""** Watershed Definition "*"******* Number of Subbasins: 1 **** **** Subbasin Number: 1 ********* ***Tributary to Node: 1 ***Bypass to Node None Area(AC res) ------- -- --- -- ----Developed -- --- Predeveloped To Node Bypass Node Include GW Till Forest 0.000 0 .000 0. 000 No Ti11 Pasture 0.000 0 .000 0. 000 No Till Grass 0.000 0 .000 0. 000 No Outwash Forest 0.000 0 .000 0. 000 No Outwash Pasture 5.200 0 .000 0. 000 No Outwash Grass 0.000 3 .290 0. 000 No Wetland 0.000 0 .000 0. 000 No Impervious 0.000 1 .910 0. 000 SUBBASIN TOTAL 5.200 5 .200 0. 000 **' Subbasin Connection Summary *'* Subbasin 1 ---- > Node 1 *'* Hy-Pass Area Connection Sum mary *** No By-Passed Areas in Watershed Pond Inflow Node 1 Pond Outflow Node: 99 Page 11 *********"*** Flow Frequency Data for Selected Recurrence Intervals ************* Subbasin 1 RunoE£ Predevelopment* Tr (Years) Flow(cf e) 6-Month 0.001 2-Year 0.002 5-Year 0.003 10-Year 0.014 25-Year 0.028 50-Year 0.08'1 100-Year 0.096 200-Year 0.135 * Recurrence Interval Computed Lsing Subbasin 1 Runoff Postdevelopmeat* Flow (cf s) 0.3"]2 0.995 0.655 0.'180 0.962 1.11'1 1.292 1.48'] Generalized Extreme Value Distribution Page 16 ****************** Water Quality Facility Data *************** Basic Wet Pond Volume (91% Exceedance): 8348. w-ft Computed Large Wet Pond Volume, 1.5*Basic Volume: 12522. cu-ft 15-Minute Timestep, Water Quality Treatment Design Discharge Discharge Rates Computed Eor Node: 1 _ On-line Design Discharge Rate (91°s Exceedance): 0.30 cfs ~-/`~Fj,77J97E~/ / Off-line Design Discharge Rate (91% Exceedance) 0.19 cfs /G~GJ S/s" S/.J x*************:e**+r:******+******x****:*****r:**x*x:******++**** 5/8/06 3:37:35 pm Skillings Connolly, Inc page 1 THE HUTCH SC 06099 ____ _____________ _ __________ __________ ______________ __________________ ________________ BASIN ____________ SUMMARY __ BASIN ID: A-100YR NAME: BASI N A - 100 YR STORM EVENT SBUH METHODOLOGY TOTAL AREA.......: 8.96 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE....: TYPElA PERV IMP PRECIPITATION....: 4.00 inches AREA..: 3.25 Acres 5.71 Acres TIME INTERVAL....: 10.00 min CN....: 76.00 98.00 TC....: 30.00 min 20.00 min ABSTRACTION COEFF: 0.20 PEAK RATE: 4.85 cfs VOL: 2.26 Ac-ft TIME : 480 min BASIN ID: A-6M0 NAME: BASIN A - 6 MO STORM EVENT SBUH METHODOLOGY TOTAL AREA:......: 8.96 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE....: TYPElA PERV IMP PRECIPITATION....: 1.28 inches AREA..: 3.25 Acres 5.71 Acres TIME INTERVAL....: 10.00 min CN....: 76.00 98.00 TC....: 30.00 min ~ 20.00 min ABSTRACTION COEFF: 0.20 PEAK RATE: 1.19 cfs VOL: 0.54 Ac-ft TIME : 480 min BASIN ZD: B-100YR NAME: BASI N B - 100 YR STORM EVENT SBUH METHODOLOGY TOTAL AREA.......: 5.20 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE....: TYPElA PERV IMP PRECIPITATION....: 4.00 inches AREA..: 3.29 Acres 1.91 Acres TIME INTERVAL....: 10.00 min CN....: 76.00 98.00 TC....: 30.00 min 20.00 min ABSTRACTION COEFF: 0.20 PEAK RATE: 2.14 cfs VOL: 1.08 Ac-ft TIME : 460 min BASIN ID: B-6M0 NAME: BASIN B - 6 MO STORM EVENT SBUH METHODOLOGY TOTALAREA.......: 5.20 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE....: TYPElA PERV IMP PRECIPITATION....: 1.28 inches AREA..: 3.29 Acres 1.91 Acres TIME INTERVAL....: 10.00 min CN....: 76.00 98.00 TC....: 30.00 min 20.00 min ABSTRACTION COEFF: 0.20 PEAK RATE: 0.40 cfs VOL: 0.20 Ac-ft TIME : 480 min 5/8/06 3:37:35 pm Skillings Connolly, Inc page 2 THE HUTCH SC 06099 DETAIL BASIN SUMMARY BASIN ID: A-100YR NAME: BASIN A - 100 YR STORM EVENT SBUH METHODOLOGY TOTAL AREA.......: 8.96 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE....: TYPElA PERU PRECIPITATION....: 4.00 inches AREA..: 3.25 Acres TIME INTERVAL....: 10.00 min CN....: 76.00 TC....: 30.00 min ABSTRACTION COEFF: 0.20 PEAK RATE: 4.85 cfs VOL: 2.26 Ac-ft TIME : 480 min IMP 5.71 Acres 98.00 20.00 min TIFID DS6I Q] TIME OSEIGN TIME -ES SGN TIME DESIGN TIME OSS IGN TIME D&$IGN RUNOFF RUNOFF RUNOFF RUNOFF RUNOFF RUNOFF (min) (c£e) (min) (c£e) (min) (c Ea) (min) (nts) (min) tees) (m In) (c£sl 10 ]10 0.9394 610 5.6831 910 1.1050 1210 O.B1O 1510 OA900 20 J20 1.0909 620 1.625] 920 1.1106 1220 0.81]") 1520 ~ 0.0266 30 3J0 1.3909 630 1.5910 930 1.1146 1230 0.81]5 1530 O.OlJB 40 0.0099 J90 1.2593 640 1.56")1 940 1.1141 1240 0.81'12 1590 0.0120 50 0.0232 ]50 1.3090 650 1.556] 950 1.11]0 1350 0.8160 1550 0.0082 60 0.0526 360 1.]9")2 660 1.5513 960 1.1206 1260 O.B155 1560 0.0056 JO 0.1032 J]0 1.J55] 6]0 1.990p 9]0 1.0]06 12]0 O.B1B9 15]0 0.0038 BO 0.3]1] J80 LJ995 680 1.3955 980 0.009] 1280 0.81"1"1 1580 0.0026 90 0.2]50 390 1.3919 690 1.3369 990 0.8016 1290 0.81]0 1590 0.0018 100 0.1916 900 1.]955 ]00 1.3094 1000 0.]93] 1300 0.8209 1600 0.0013 110 0.]408 410 1.J56] "I30 1.3811 1010 0,]090 1]10 0.8191 1fi 30 0.0009 120 0.]828 920 1.J660 ]20 1.26]2 1040 0.68J6 ll20 0.8189 1620 0.0006 1J0 0.9 J95 930 1.")006 ]30 1.4629 10]0 0.]JOB 1]]0 0.]893 1630 0.0004 190 0.49J6 990 2.29J9 ]90 1.2566 1090 0.8181 1]40 0.]424 1640 0.0003 150 0.5391 450 4.5939 ]50 1.35]6 1050 0.8]28 1]50 0.]130 1650 0.0002 160 0.5]2") 960 3.2969 760 1.2558 1060 0.90]5 1]60 0.6909 1660 0.0002 1")0 0.6033 UO 4.3298 7]0 1.254] 10"/0 0.9296 1]]0 0.6806 16]0 0,0001 180 0.6261 480 4.8963 ]80 1.2541 1080 0.9990 1]00 0.6]41 1680 190 0.6934 990 9.6116 ]90 1.1900 1090 0.9349 1]90 0.6669 1690 200 0.660] 500 3.83'!5 800 1.1055 1100 O.BB1] 1900 0.6651 1]00 310 0.6]52 510 3.]]05 810 1.04]6 1110 0.8543 1910 0.664] 1J10 220 0.6850 520 3.0390 830 1.0115 1120 0.9983 1920 0.6602 1]20 330 0.6969 90 2.]]93 B]0 0.9091 1130 0.0965 1930 0.6612 3]JO 290 0.]061 540 2.6269 840 0.9]52 1190 0.7572 1990 0.6621 3J90 250 0.]J95 550 2.]959 050 0.999] 1150 0.'1809 1950 O. SJ 96 1]50 260 0.]]91 560 2.1199 860 1.OJ86 1160 0.]911 1460 0.39]9 1]60 2]0 O.B004 5")0 1.9410 8]0 1.0665 11]0 0.]991 19]0 0.2201 1]JO 280 O. Bd 11 580 1.BJ 99 880 1.0808 1180 0.80]1 1980 0.1421 1]BO 390 0.0]29 590 1.]J]5 890 1.0939 1190 0.8089 1990 0.0929 1]90 ]00 0.8420 600 1. ]J]8 900 1.1025 1200 0.8098 1500 0.0606 1800 5/8/06 3:37:35 pm Skillings Connolly, Inc page 3 THE HUTCH SC 06099 DETAIL BASIN SUMMARY BASIN ID: A-6M0 NAME: BASIN A - 6 MO STORM EVENT SBUH METHODOLOGY TOTAL AREA.......: 8.96 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE....: TYPElA PERU PRECIPITATION....: 1.28 inches AREA..: 3. 25 Acres TIME INTERVAL....: 10.00 min CN....: 76. 00 TC....: 30. 00 min ABSTRACTION COEFF: 0.20 PEAK RATE: 1.19 cfs VOL: 0.54 Ac-ft TIME: 480 min IMP 5.71 Acres 98.00 20.00 min TIME DESIGN TIME DE6IGN TIME DESIGN TIME DESIGN TIME DEE SGN TIME DESIGN RUNOFF RVNOFP RUNOFF RONO FP RUNOFF RUNOFF (mint (c Eel (min) (cfal (mial (cfs) (min) (c£el (min) (c fa) (min) (cfs) l0 310 e.n]e fila 0.3961 910 e.nn mo o.zo ]3 lsl0 e.oe e3 20 320 0.2563 620 0.]B]] 920 0.2]6] 1220 0.20D 1520 ~ 0.005] 30 330 O.d B]0 630 0.]]69 930 0.2]00 1230 0.20]9 1530 0.0039 40 340 0.3021 690 0.]]26 990 0.2]00 1z 90 0.2005 1590 0.0022 50 350 0.3162 650 0.]]15 950 0.3]92 1250 0.208) 1550 O.OOls 60 160 0.]2]1 660 O.J]15 960 0.2002 1260 0.20 BJ 1560 0.0010 ]0 3]0 0.]302 6]0 0.]5]1 9]0 0.256] 12]0 0.209] 15]0 0.0006 80 380 0.]203 600 0.33]9 980 0.2300 1200 0.2091 1580 0.0009 90 0.0005 ]90 0.]281 690 0.3203 990 0.19]] 1290 0.2090 1590 0.0003 100 0.0818 900 0.]294 ]00 0.]ll] 1000 0.1832 1300 0,2101 1600 0.0002 110 0.0106 910 0.3]2] ]10 0.3086 1010 0.1]54 1310 0.2090 1610 0.0001 120 0.0192 420 0.]39] ]20 0.3061 1020 0.1]06 1320 0.2090 1620 130 0.0]0] 9J0 0.4180 ]]0 0.3059 1030 0.1828 1330 0.2021 1630 140 0.0939 490 0.5595 ]90 0.3052 1040 0.3069 1390 0.189] 1640 150 O.OS59 950 0.6905 ]50 0.3052 1050 O.d208 1350 0.1821 1650 160 0.06]5 460 0.019s ]60 0.3069 1060 O.zz90 1]60 0.1]66 1660 1]0 0.0]88 4]0 1.0939 ]]0 0.3066 30]0 0.2]55 13]0 0.1]42 16]0 100 O.OB91 980 1.109] ]00 0.30]1 1000 0.2391 1]BO 0.1 ]2B 1600 190 0.098) 990 1.119] ]90 0.2931 1090 O. 21J9 1290 0.1]09 1690 200 0.10]] 500 0.91]3 800 0.2695 1300 0.2229 1900 0.1]09 1]00 210 0.1155 510 0.]968 010 O.d 553 1110 0.2159 3410 0.1]00 1J10 220 O. 1z 26 520 0.]119 020 O. d469 1120 0.2900 1920 0.1699 1]z0 90 0.129] 530 0.6901 030 0.2920 1110 0.2269 1430 0.1]09 1]]0 290 0.1362 590 0.611] 890 0.2392 1190 0.1899 1990 0.1]0] 1]90 250 0.1966 550 0.5562 Bs0 0.2450 1150 0.19]0 1950 0.13]] 1]s0 z60 0.1593 560 0.4886 860 0.2s]0 1160 0.2004 1960 O.Oesl 1]60 z]0 0.1692 5]0 0.4490 0]0 0.2645 11]0 0.2026 19]0 0.0529 I]]0 280 0.1]]9 580 0.4269 000 0.2604 1180 0.2099 1980 0.0330 1JB0 390 0.1896 590 0.41]6 890 0.2]19 1190 0.2055 1990 0.020] 1]90 300 0.1905 600 0.4065 900 0.2]4] 1300 0.2060 1500 0.0131 1000 5/8/06 3:37:35 pm Skillings Connolly, Inc page 4 THE HUTCH SC 06099 ________________________DETAIL BASIN SUMMARY_________________________ BASIN ID: B-100YR NAME: BASIN B - 100 YR STORM EVENT SBUH METHODOLOGY TOTAL ARE A.... ...: 5.20 Acres BASEFLOWS: 0.00 cfs RAINFALL TYPE. ...: TYPE lA PERU IMP PRECIPITATION.. ..: 4.00 inches AREA..: 3.29 Ac res 1.91 Acres TIME INTERVAL.. ..: 10. 00 min CN....: 76.00 98.00 TC_...: 3 0.00 mi n 20.00 min ABSTRACTI ON COEFF: 0.20 PEAK RATE : 2 .14 cfs VOL : 1. 08 Ac-ft T IME: 480 min TIME DESIGN TIME DESIGN TIME DESIGN S3ME DESIGN SIME DE6IGN TIME DESIGN RUNOFF RNNOFF RUNOFF RUNOFF RUNOFF RDNOFF (min) Icf s) (mivl (cE SI (min) Icfs) _ (miv) _~ . (cfs) . (miv) a~ (cf e) ~ (mivl (c Eel - ___ 10 _- __~~ _________ 310 __________ 0.]15] __ __ _ 610 _ _ _ _ 0.0991 _ _ _ 910 ______ ____ 0.5]]9 ____ 1210 ____ _______ 0.9 5] ________ 1530 _______ 0.0209 20 320 0.]]05 620 0.8220 920 0.5815 1220 0.9J SJ 1520 ~ 0.0200 30 3]0 0.9109 630 O.BO56 9]0 0.5093 1230 0.4354 1530 O.O3J9 40 0.0016 390 0.9416 640 0.]99J 990 0.5899 1340 0. 4J ]9 1590 0,009] 50 0.00]0 350 0.46]4 650 0.]09] 950 0.58]5 1350 0.9]]3 1550 0.0068 60 0.01]6 360 0.9900 660 0.]8]8 960 0.5895 1260 0.4]]1 1560 0.004] ]0 0.0]45 3]0 0.5019 6le 0.]601 9]0 0.5466 12]0 0.9]91 15]0 0.00]J 00 0.05]3 380 0.5066 680 0.]156 980 0.4]]6 1200 0.9]8] 1580 0.0024 90 0.0 ]B6 390 0.51]9 690 0.68]9 990 0.4]25 1290 0.4386 1590 0.001] 100 0.09]6 900 0.52]6 "100 0.6]12 1000 0.4013 1]00 0.4905 1600 0.0012 110 0.1190 910 0.5358 ]30 0.6596 1010 0.382) 3]10 0.4901 1610 0.0008 130 0.1281 420 0.59]0 ]20 0.6525 1020 0.3698 1J20 0.4400 1630 0.0006 1]0 0.1453 9J0 0.600] ]30 0.6501 1030 0.3891 1J30 0.4258 16]0 0.0004 190 0.1651 990 0.9199 J40 0.64]5 1040 0.9]10 1J90 0.4024 1690 0.000] 150 0.1003 950 1.0010 ]50 0.646] 1050 0.4586 3]50 0.38"11 1650 0.0002 160 0.1916 960 1.390] ]60 0.69]8 1060 0.4]]0 1J 60 0.325) 1660 0.0002 120 0.2019 920 3.022] ]]0 0.64]8 10]0 0.4899 1]20 0.3694 16]0 0.0001 100 0.2099 980 2.1395 ]BO 0.6409 1080 0.99]9 1J80 0.]659 1680 190 0.3152 990 3.0029 290 0.6222 1090 0.9099 3J90 0.]631 1690 200 0.2210 500 1.]]]9 800 O.PB1 1100 0.969] 3900 0.]600 1]Oc 210 0.2250 510 1.5912 810 0.5494 1110 0.9561 1410 0.3593 1210 220 0.2291 530 1.4530 020 0.900 1120 0.5010 1420 0.]5]1 D20 2J0 0.2330 90 3.J922 030 0.5109 1130 0.9]]6 1430 0.35]5 3]30 290 0.2362 590 1.2032 840 0.511] 1190 0.409] 1490 0.35]9 3]40 250 0.295] 550 3.1015 850 0.5199 1150 0.4196 3950 0.29]2 1]50 260 0.2509 560 1.0543 860 0.5910 1160 0.4292 3960 0.1982 1260 2]0 0.26]] 5]0 0.9]]9 8]0 0.5551 11]0 0.92]] 14]0 0.1332 1]]O 300 0.2]96 580 0.9290 080 0.56]0 1180 0.9312 1480 0.0901 1]00 290 0.2]86 590 O.B93] 890 0.5209 1190 0.9321 1990 0.O61J 1290 J00 0.2812 600 0.8]31 900 0.5]56 1200 0.4329 1500 0.0930 1800 5/8/06 3:37:35 pm Skillings Connolly, Inc page 5 '^HE HUTCH ~~ 06099 ________________ DETAIL BASIN SUMMARY BASIN ID: B-6M0 NAME: BASZN B - 6 MO STORM EVENT SBUH METHODOLOGY TOTAL AREA.......: 5.20 Acres BASEFLOWS: 0.00 cfS RAINFALL TYPE....: TYPElA PERV IMP PRECIPITATION....: 1.28 inches AREA..: 3.29 Acres 1.91 Acres TIME INTERVAL....: 10.00 min CN....: 76.00 98.00 TC....: 30.00 min 20.00 min ABSTRACTION COEFF: 0.20 PEAK RATE: 0.40 cfs VOL: 0.20 Ac-ft TIME: 480 min TII~ D65IGN TIIID DESIGN TIME DESIGN TI1~ffi DESIGN TIME DESIGN TIME DPSIQI AVNO PP RDNOFF RDNOFF RIIIiOFF RVNOPP AVNOFF (min) (cfsl (min) Icf ~) (min) (c fa) (mint lee=1 (min) fete) (min) (cep) 10 J10 0.0]26 610 0.1402 910 e.110J 3210 0.0900 1510 0.0098 20 ]20 0.005] 620 0.1360 920 0.311] 1220 O.OB01 1520 O.O OJ2 30 330 0.094] 630 0.335] 930 0.1121 1230 0.0883 1530 0.0022 90 390 0.1010 690 O. 1J 9t 940 0.1124 1290 0.0009 1590 0.0015 50 350 0.1050 650 0.1351 950 0.1132 1250 0.0009 1550 0.0010 60 J60 0.1099 660 0.1360 960 O.11J9 3260 0.0091 1560 0.000] 00 3]0 0.1105 6]0 0.1315 9]0 0.1050 12]0 0.0096 15]0 0.0005 00 380 0.1098 600 0.12J0 900 0.0908 1200 0.009] 1580 0.0003 90 0.0002 390 0.109] 690 0.1199 990 0.0820 1290 0.0090 1590 0.0002 100 O.OO lJ 900 0.1102 ]00 0.11"13 1000 0.0]62 3]00 0.090] 1600 0.0002 110 0.00]5 910 0.1112 ]10 0.1161 1010 0.0]29 1]10 0.090] 1630 0.0001 120 0.0064 420 0.3119 ]20 0.1156 3020 0.0]09 1320 0.0905 1620 1J0 0.0101 930 0.1401 ]30 0.1160 lOJO 0.0]56 1330 0.08]4 1630 140 0.0145 990 0.1855 ]90 0.1162 1090 0.0049 1J40 0.0024 1690 150 0.010] 950 0.2142 ]50 0.1166 3080 0.0909 1350 O.O]9J 3650 160 0.0226 960 0.2]25 ]60 0.11]5 1060 0.099] 1360 0.0]]0 1660 1]0 0.0263 9]0 0.]992 ]]0 0.1100 10]0 0.09]3 13]0 0.0]59 16]0 180 0.0290 900 0.39]9 ]80 0.1186 1080 0.0990 1300 0.0]53 1600 190 0.0329 990 0.3]96 ]90 0.1130 1090 0.091] 1J90 0.0]46 3690 200 0.0]59 500 0.3060 900 0.1051 1100 0.0929 1400 0.0]95 1]00 210 0.0386 510 0.2665 810 0.3001 1110 0.0903 1910 0.0]96 1]10 220 0.0910 520 0.3300 020 0.09]1 1130 0.1005 1920 0.0]42 1]20 2]0 0.0934 5J0 0.21]1 030 0.0959 1130 0.0952 19]0 0.0]99 1]30 290 0.0956 590 0.2059 090 0.0995 1190 0.0006 1990 0.0]46 1]90 250 0.0990 550 0.1092 050 0.0969 3150 0.0033 1450 0.0611 1]50 260 0.0533 560 0.1664 060 0.101] 1160 0.084] 1460 0.0392 1]60 2]0 0.0566 540 0.1590 0]0 0.1049 11]0 0.0056 14]0 0.0254 1]]0 200 0.0595 580 0.14]6 880 0.106] 1180 0.096] 1900 0.0165 1]00 290 0.063] 590 0.1442 090 0.1094 1190 0.00]0 1990 0.0300 1]90 J00 O.O6J] 600 0.1920 900 0.1096 1200 0.08]3 1500 0.0032 1000 5/8/06 3:37:35 pm Skillings Connolly, Inc page 6 THE HUTCH SC 06099 _____________________________________________________________________ ____________________ DETAIL HYDROGRAPH SUMMARY HYDROGRAPH No. 1 Peak runoff : 1 .1897 cfs Total Vol: TIME DESIGN TIME DCSIGN TIME DRSIGN TIME DESIGN TIME RUNOFF RUNOFF RDNOFF RUNOFF (miNl Ic Ea) (min) Ic£e) Iminl Ic£el (mint (c£sl Im1n1 10 410 0.332] 810 0.2553 1210 0.20]3 1610 20 920 0,339] 820 0.2469 1220 0.20]3 1620 30 430 0.9188 830 0.2920 1230 0.20]4 1630 90 990 0.5595 840 0.2392 1290 0.2085 1640 50 450 0.6905 050 0.2450 1250 0.2083 1650 60 960 O.B195 860 0.25]0 1260 0.2083 1660 >0 9]0 1.04]9 840 0.2645 12]0 0.2093 16]0 BO 980 1.189] BBO 0.2689 12 B0 0,2091 1680 90 0.0005 990 1.319] 890 0.3]19 1290 0.2090 1690 loo e.aa3e see 0.9 v3 900 e. n43 veo e.uol vee 110 0.0106 510 0.]968 910 0.2>51 1310 0.2098 1]10 IIO 0.0192 520 0.]119 920 0.2]6] 1320 0.2090 1]20 130 0.030] 530 0.6481 930 0.2]80 1330 0.2021 1]30 140 0. 09 J9 590 0.611] 940 0.2]80 1390 0.109] 1>90 150 0.0559 550 0.5562 950 0.2]92 1]50 0.3821 1]50 160 0.06]5 560 0.4886 960 0.2802 1360 0.1>66 1]60 1]0 0.0>88 5]0 0.4490 9>0 0.256] 13]0 01]92 1]>0 180 0.0891 500 0.4269 980 0.3200 1J B0 0.1]28 1]BO 190 0.0983 590 0.9136 990 0.19]] 1390 0.1]09 1]90 200 0.10]3 600 0.4065 1000 O.1 BJ2 1900 0.1]09 3800 210 0.1155 610 0,3961 1010 0.1]54 1410 0.1>OB 1810 220 0.1226 630 0.383] 1020 0.1]06 1420 0.1699 1820 230 0.129] 6]0 O.J]69 lOJO O.1 B20 1930 0.1]09 1830 390 0.1362 640 O.J]26 1090 0.2064 1490 0.1]0] 1840 250 0.1466 650 0.3]15 1050 0.2200 1450 0.13]] 1850 260 0.1593 660 0.]]15 1060 0.3398 1960 0.0851 1860 2]0 01692 6>0 0.]5>1 10]0 0.2]55 19]0 0.0539 18]0 200 0.1]]9 600 O.J339 3000 0.2391 1980 0.0330 1880 390 01096 690 O.J203 1090 0.23]9 1990 0.030] 1090 ]00 0.1905 ]00 0.3133 3100 0.2229 1500 0.01]1 1900 31- 0.21]0 ]10 0.3086 3110 0.2154 1510 O.OO B3 1910 320 0.256) ]20 O.JO61 1120 0.2908 1520 O.OO SJ 1920 ]30 0.2830 ]30 0.3059 1130 0.2269 15]0 0.0039 1930 390 0.3021 >40 0.3052 1140 0.1899 1590 0.0032 1940 ]50 0.3162 >50 0.3052 1150 0.19]0 1550 0.0015 1950 J60 0.]2>3 ]60 0.3069 1160 0.2009 1560 0.0010 ]960 3]0 O.J]02 ]]0 0.3066 11]0 0.2026 15]0 0.0006 39]0 300 OJSBJ >00 0.30>1 1100 0.2049 1500 0.0004 1980 390 0.]281 ]90 0.29J1 1190 0.2055 1590 0.0003 3990 400 0.]294 800 0.3695 1300 0.3060 1600 0.0003 2000 0.54 ac-ft DESIGN RUNOFF (rfal 0.0001 5/8/06 3:37:36 pm Skillings Connolly, Inc page 7 THE HUTCH SC 06099 _____________________________________________________________________ ____ ________________________________________ DETAIL HYDROGRAPH SUMMP.RY HYDROGRAPH No. 2 Peak runoff : 4 .8463 cfs Total Vol: 2.26 ac-ft TIME DESIGN TIME OSSIGN TIME DESIGN TIME DESIGN TIME DESIGN RUNOFF RUNOFF RUNOFF BONOFF RUNOFF (min) Ic ES) Imin) (c Fs) (min) IcEe) (min) IcEe) (mint Icfel 10 410 1.356] 010 1. 09 J6 1210 0.8143 1610 0.0009 20 920 1,3660 820 1.0115 1230 O.BllJ 1630 0.0006 30 430 1.J006 830 0.9891 1230 0.8135 1630 0.0004 40 0.0099 490 2.2934 840 0.9]52 1290 0.81]2 1690 0.0003 50 0.0232 950 2.5939 050 0.999) 1250 0.8160 1650 0.0002 60 0.0526 460 J.2969 060 1.0386 1360 0.0155 3660 0.0002 ]0 0.1032 4]0 4.2298 8]0 1.0665 13J0 0.0109 16]0 0.0001 eO 0.1]13 400 9.8963 880 1.0800 1280 0.81]] 3680 90 0.2350 490 9.6116 090 1.0939 1290 0.81]0 3690 100 0.2916 500 3.83 J5 900 1.1025 1300 0.8204 1]OO 110 0.3900 510 ].J]OS 910 1.1050 1310 0.8191 1J10 120 O.J028 520 3.0390 920 1.1106 1]20 0.8189 1]20 1J0 0.9395 530 2.]]92 9]0 1.1196 1]10 0.]893 - 1J30 190 0.4936 590 2.6369 990 1.1193 1]90 0.]929 1]40 150 0.5]91 550 2.J959 950 1.11]8 1350 O.J1J0 1]50 160 0.5]2] 560 3.3199 960 1.1206 1360 0.6909 1]60 1J0 0.6022 5]0 1.9418 9J0 1.0306 1]]O 0.6006 1]]0 380 0.6361 580 1.8J 94 980 O.BB9] 1300 0. 6J91 1]80 190 0.64]9 590 1.]]35 990 0.8016 3]90 0.6669 1]90 2OO 0.660] 600 1.]JJB 1000 0.]92] 1400 0.6651 1800 210 0.6]52 610 1.6031 1010 O.J090 1910 0.669) 1010 330 0.6E50 620 1.635] 1030 O.6BJ6 1920 0.6602 1020 230 0.6969 630 1.5910 1030 O.DOB 1930 0.6613 1030 240 0.]061 690 1.56]1 1040 O.B1B1 1990 0.6631 1890 250 0.]395 650 1.556] 1050 O.BJ28 1950 0.5396 3850 260 0.]]91 660 1.5513 1860 0.90]5 1960 0.3434 1860 280 0.8211 600 1.3955 1080 0.9940 1980 0.1421 3880 290 0.8329 690 1.3369 1090 0.9399 1990 0.0929 3890 300 O.B920 J00 1.J044 1100 0.001] 1500 0.0606 1900 310 0.9394 ]10 1.2811 1110 0.854] 1510 0.0900 1910 320 1.0909 ]20 1.26]2 1120 0. 998J 1520 0.0266 1920 330 1.190) ]30 1.2639 1130 0.0965 15]0 O.O1J8 19J0 390 1.2593 ]90 1.2566 3140 0.]5]2 1590 0.0120 1990 350 1.3090 ]50 1.3536 1150 0.]809 1550 0.0082 1950 ]60 1.J9 J3 J60 1.2550 1160 0.]931 1560 0.0056 1960 ]]0 1.J55] ]]0 3.2543 11]0 0.]991 15]0 0.00]8 19]0 300 1.3995 ]BO 1.3591 1100 0.80]1 1580 0.0026 1900 J90 1.J919 ]90 3.1988 1190 0.008] 1590 0.0018 1990 900 1.J955 800 1.1055 1200 O.B098 3600 0.0013 2000 5/8/06 3:37:36 pm Skillings Connolly, Inc page 6 THE HUTCH SC 06099 _____________________________________________________________________ _____________________________________________________________________ DETAIL HYDROGRAPH SUMMARY HYDROGRAPH No. 3 Peak runoff : 0 .3979 cfs Total Vol: TIME nS52GN TIME DESIGN TIME DESIGN TIME n85IGN TIME RUNOFF RUNOFF RDNO£F RNiD FF Iminl (c Ps) (min) Iceol (min) (c esl Iminl (ciB) (min) 1a 410 o.ll lz elo 0.1003 1230 o.oeea 3610 20 420 0.1119 820 0.09]1 3220 0.0081 1620 30 430 0.1901 830 0.0959 1230 OABB3 1630 40 990 0.1055 G40 0.0945 1290 O.OBB9 1690 50 450 0.2192 850 0.0969 1250 0.0889 1650 60 960 0.2]25 860 0.101] 1260 0.0091 1660 ]0 9]0 0.3492 0]0 0.1098 12]0 0.0896 36]0 BO 980 0.39]9 880 0.106] 1200 O.OB9> 3680 90 0.0002 990 0.3]96 890 0.1084 1290 O.OB9B 1690 300 0.001] 500 0.3068 900 0.1096 1300 0.0903 1]00 110 0.00]5 510 0.2665 910 0.1103 1310 0.090] 1]10 120 0.0064 520 0,2380 920 0.111) 1]20 0.0905 1"120 ll0 0.0101 530 0.21]1 930 0.1121 1330 0.00]4 1]30 190 0.0145 590 0.2058 990 0,1129 1340 0.0829 1]90 150 0.018> 550 0.1882 950 0.1132 1350 0.0]91 1]50 160 0.0226 560 0.1669 960 0.1139 1360 0.0]]0 1]60 1]0 0.0263 5>0 0.1590 9]0 0.1050 13]0 0.0]59 1]]0 100 0.0298 SBO 0.19]6 900 0.0908 1J80 0.0]53 1]00 190 0.0329 590 0.1942 990 0.0820 1390 0.0]96 1]90 200 0.0359 600 0.1920 3000 0.0]62 1900 0.0]45 1000 210 0.0386 610 0.1902 1010 0.0]29 1910 0.0]96 1810 220 0.0410 620 0.1368 3020 0.0]09 1420 0.0]42 1820 230 0.09]9 630 0.1353 1030 0.0]56 1930 0.0>99 3830 390 0,0956 690 0.139] 1040 0.0899 1990 0,0]96 3890 350 0.0990 650 0.1351 1050 0.0909 3450 0.0611 3850 260 0.053) 660 0.1]60 1060 0.094] 3960 0.0392 3060 2>0 0.0566 6]0 O.D15 30>0 O.o9]3 39]a 0.0259 36>0 280 0.0595 680 0.1230 1000 0.0990 1980 0.0165 1080 290 0.061] 690 0.1199 1090 0.09]3 1490 0.0100 1090 J00 0.06]] ]00 0.31]] 1100 0.0929 1500 0.00]2 1900 ]30 0.0]26 ]10 0.3161 1110 0.0903 1510 0.0048 1910 ]30 0.085] ]20 0.1156 1120 0.1005 1520 0.00]3 1920 IDO 0.099] ]30 0.1160 1130 0.0952 1530 0.0022 19]0 ]90 0.1010 ]90 0.3162 1140 0.0806 1590 0.0015 1990 ]50 0.1050 ]50 0.1166 1150 0.083] 1550 0.0010 1950 360 0.1099 ]60 0.11]5 1160 O.O B9] 1560 0.000] 1960 3]0 0.1105 ]]0 0.1180 11]0 O.OB56 15]0 0.0005 19]0 380 0.1098 ]80 O.11B6 1180 0.086] 1500 0.0003 1980 390 0.109] ]90 0.1138 1190 O.OB]0 1590 0.0002 1990 400 0.3102 800 0.1053 1200 0.08 ]J 1600 0.0002 2000 0.20 ac-ft nes1GN RUNOFF Ic[3) o.oool 5/8/06 3:37:36 pm Skillings Connolly, Inc page 9 THE HUTCH SC 06099 __________________ ________________________________________ DETAIL HYDROGRAPH SUMMARY HYDROGRAPH NO. 4 Peak runoff : 2 .1395 cfs Total Vol: 1.08 ac-ft TIME DESI QI TSME -ESIGN TIME D&SIGN SIM6 DEEIGN TIME DESIGN RUNOFF RUNOFF RDNOFF RNJO FF RUNOFF fmin) Ices) (min) (cfs) (min) (c EaJ (min) lcf e) Imin) (c Eel 10 910 0.5358 B1O 0.5494 1210 0.9353 1610 0.0008 20 920 0.54]0 020 0.5309 1220 0.9353 1620 0.0006 30 930 0.699] 830 O.S1B9 1230 0.4354 1630 0.0009 90 0.0016 990 0.9194 090 0.5113 1290 0.93>9 1640 0.0003 $O 0.00>B 950 1.0810 050 0.5199 1250 0.93]2 1650 0.0002 60 0.01]6 960 1.390] 860 0.5410 1260 0.4J]1 1660 0.0002 >O 0.0395 9>O 1.02]] 0]0 0.5551 12]0 0.4391 16>0 0.0001 00 0.05]3 400 2.1395 000 0.56]0 1200 0.930] 1600 90 0.0>96 490 2.0029 990 0.5]04 1290 0.9386 1690 100 0.09>6 500 1.]]]9 900 O.SJ56 1300 0.9905 1>00 110 0.1190 510 1.5912 910 O.5 ]]9 1310 0.9901 1>30 120 0.1281 520 1.4538 920 0.5815 1320 0.9900 3>20 ll0 0.1953 5]0 1.34]2 930 0.5043 1330 0.9258 1]]0 - 190 0.1651 540 1.2932 940 O.SB49 1390 0.9029 1]90 150 0.1903 550 1.1815 950 0.58>5 1350 0.38>1 ll50 160 0.1916 560 1.0593 960 0.5895 ]J 6O 0.3]53 1]60 1]0 0.2019 5]0 0.9]]9 9>0 0.5466 ll]0 O.J699 1»0 180 0.2099 580 0.9248 980 0.4]]6 1300 O.J659 1>BO 190 0.2152 590 0.892> 990 0.4]25 1390 O.J611 1>90 200 0.2210 600 0.8]]1 1000 0.901) 1900 0.]600 1800 210 0.2258 610 0.8991 1010 O.JBD 1910 O,J593 1930 230 0.2291 620 0.9220 1020 0.3699 1420 0.35]1 1020 330 0.2]30 630 0.9056 1030 O.J 891 1430 0.]5]5 10]0 240 0.2]62 690 0.>99] 1040 0.4]10 1490' 0.]5>9 1940 250 0.245] 650 0.]B9> 3050 0.4506 1950 0.29>2 1850 260 0.2509 660 0.]B>8 1060 0.9]]0 3960 0.1982 1860 2]0 0.26>] 610 0.]601 SO>0 0.9099 la]a 0.1332 16]0 280 0.2]96 690 0.]156 3080 0.49]9 1480 0.0901 1880 290 0.2]06 690 0.60>9 3090 0.9899 1490 0.0613 1090 300 .0.281] >00 0.6]12 1100 0.969] 1500 0.0420 1900 330 0.315> ]10 0.6596 1110 0.4561 1510 0.0209 1910 320 0.3>O$ ]20 0.6525 1120 0.5010 1520 0.0200 1920 ]JO 0.9109 ]30 0.6501 I1J0 0.9 J>6 15]0 0,0139 1930 340 0.9916 ]40 0.69>5 1190 0.409] 1540 0.009] 1940 J50 0.46]4 ]50 0.646] 1150 0.9196 1550 0.0069 1950 360 0.9900 ]60 0.69>8 3160 0.9292 1560 0.009] 1960 ]>0 0.5019 >]0 0.69]8 11]0 0.92>3 15]0 0.0033 19>0 ]90 0.5066 ]00 0.6904 1180 0.9]12 1580 0.0024 1980 J90 O.Sll9 ]90 0.622] 1190 0.9321 1590 0.001] 1990 400 0.5336 800 0.5]81 1200 0.4]29 1600 0.0012 2000 5/8/06 3:37:36 pm Skillings Connolly, Inc page 10 THE HUTCH SC 06099 _____________________________________________________________________ DETAIL HYDROGRAPH SUMMARY HYDROGRAPH No. 11 Peak runoff : 1 .1626 cfs Total Vol: TIME DESIGN TIME DESIGN TIME D65IGN TI!ffi -£S IGN TIMR RDNOFF RUNOFF RGNGFF RUNOFF Imin) (cfa) (min) Icf s) Imin) (cfa) (min) (cfa) (min) 10 410 0.3291 810 0.2]55 1210 0,2059 1610 20 420 0.]]15 020 0.25]0 1220 0.2069 1620 3o aJO aa34z 830 o.z4ee 123a o.zo]4 1630 40 440 0.3918 090 0.2429 1290 0.20]3 1690 50 450 0.5204 850 0.2398 1250 0.2081 1650 60 960 0.6299 060 0.2929 1260 0.2085 1660 ]0 9]0 0.]640 8]0 0.2538 12]0 0.2082 16]0 BO 480 0.9880 880 0.2632 3280 0.2090 1680 90 490 1.1626 090 0.26]6 1290 0,2093 1690 100 0,0004 500 1.1519 900 0.2]11 1300 0.2090 1]00 110 0.0028 510 0.9]11 910 0.2]39 1310 0.2098 1]10 120 0.008] 520 0.0165 920 0.2]50 1J20 0.2100 1]20 3]0 0.01]1 530 0.]319 930 0.2]62 1330 0.209] 1]30 190 0.02]5 540 0.6612 990 0.2]]0 1]90 0.2096 1]90 150 0.0402 550 0.6188 950 0.2]81 1]50 0.1928 1]50 160 0.0530 560 0.5]16 960 0.2]88 1]60 0.1035 1]60 1]0 0.0698 5]0 0.5099 9]0 0.2800 1]]0 0.3]]9 1]]0 100 0.0]61 580 0.4559 900 0.269) 1380 0.1]95 1]80 190 O.OB6] 590 0.4315 990 0.2291 1390 0.1]31 1]90 2OO 0.0962 fi00 0.9162 1000 0.201] 3900 0.3]19 1000 210 0.1051 610 0.90]8 1010 0.1065 1410 0.3]0] 1810 220 0.1136 620 0.3990 1020 0.1]60 1420 0.1]09 1820 230 0.1209 630 0.386] lO]0 0.1]1] 1430 0.1]02 1830 290 0.1200 690 0.3]80 3040 0.1]85 1940 0.1]01 1090 250 0.1340 650 0.3]36 1050 0.2003 1450 0.1]0] 1050 260 0.1938 660 0.3]15 1060 O.S1B] 1960 0,198) 1860 280 0.16A 680 0.3618 1000 0.2399 1480 0.0586 1880 290 0.1]59 690 0.3]9] 1090 0.2]84 1490 0.03]4 1890 ]00 0.1832 ]00 0.3226 1100 0.2359 1500 0.0231 1900 330 0.1091 ]30 0.3198 1110 0.2254 1510 0.019] 1910 320 0.2090 ]20 0.3096 1120 0.2166 1520 0.0093 1920 330 0.2465 DO 0.3066 1130 0.2322 1530 0.0060 19]0 390 0.2]]9 ]90 0.3050 1190 0.2399 1590 0.0030 1940 350 0.29]0 ]50 0.3055 1150 0.1992 1550 0.0025 1950 J60 0.]131 ]60 O.JO51 1160 0.1919 1560 0.0016 1960 3]0 0.3246 ]]0 0.3060 11]0 0.2013 15]0 0.0011 39]0 300 0.3301 ]80 0.306] 1180 0.2016 1580 0.000] 1900 J90 0.]290 ]90 0.3069 1190 0.2095 1590 0.0005 1990 400 0.]2]9 800 0.291] 1200 0.2055 1fi 00 0.000] 2000 0.54 ac-ft -ESIGN RUNOFF (cfa) a.aoo2 o.aool o.oom 5/8/06 3:37:36 pm Skillings Connolly, Inc page 11 THE HUTCH SC 06099 DETAIL HYDROGRAPH SUMMARY HYDAOGRAPH No. 12 Peak runoff : 1. 9670 cfs Total Vol: TIME -ESIGN TIME DESIGN TIME DESIGN TIME OFS IGN TIME RUNOFF RUNOFF RUNOFF RUNOFF Iminl (c PS) Imin) (cfe) (min) (cfs) (minl (c FS) (min) 10 910 1 3442 810 1.96]0 1210 0.0095 1610 20 420 1.3535 820 1.96>0 3220 0.0130 1620 30 +30 1.3691 930 1.96]0 123a 0.9144 1630 90 440 1.5935 890 1.96]0 1290 O.Bll] 1640 50 0.00]] 950 1.96]0 850 1.96J0 1250 0.0160 1650 60 0.01>9 460 1.96J0 860 1.4993 1260 0.8168 1660 ]0 0.0951 9]0 1.96>0 9]0 0.0696 12 J0 0.8154 16]0 90 0.0096 480 3.96>0 880 1.1199 1280 0.91>9 1600 90 0.1542 990 3.96>0 890 1.OSJ4 1290 0.0185 1690 100 0.2205 500 1.96]0 900 1.0900 1300 O.B1>0 1J00 110 0.2J05 510 1.96]0 910 1.090] 1310 0.8199 1>30 120 0.]296 40 1.96]0 920 1. ID5> 1J 20 0.8199 1>20 ll0 O.JJJ2 5]0 1.96]0 9]0 1.1005 1330 0.8109 1>30 140 0.9212 590 1.96J0 990 1.1191 1390 0.]98] 1>90 150 0.9>93 550 1.96>0 950 1.1195 1350 0.]592 1]50 160 0.5295 560 1.96>0 960 1.1165 1360 0.]183 1>60 1>0 0.5653 5>0 1.96>0 9>0 1.1201 13>0 0.6962 1JJ0 180 0.5959 SBO 1.96]0 900 1.0598 1380 0.6821 1>BO 190 0.6200 590 1.96]0 990 0,9249 1390 0.6>5] 1J 90 200 0.639] 600 1.96]0 1000 0.01>5 1400 0.6603 1000 210 0.6565 610 1.96>0 1010 0.>560 1910 0.6698 1810 220 0.6>20 620 1.96>0 1020 0.>151 1920 0.669] 1020 630 0.6029 6]0 1.96>0 1030 0.6923 14J0 0.6614 1930 290 0.6935 690 1.96]0 1090 0.]ls2 1940 0.6606 1940 250 0.]091 650 1.96>0 1050 0.]955 1450 0.6621 1060 260 0.]261 660 1.96>0 1060 0.86]2 3960 0,993 1860 2>O O.J643 6>0 1.96]0 SO>O 0.899e 19]0 0.3926 10>O 200 0.]954 680 1.96]0 1000 0.9253 1400 0.2929 1880 290 0.0162 690 1.96J0 1090 0.9909 1490 0.159] ]090 300 0.8300 >00 1.96]0 1100 0.9322 1500 0.102] 1900 310 0.0]90 ]10 3.96>0 1110 0.0920 1510 0.06>3 3910 320 0.9088 >20 1.96]0 1120 0.0589 1520 0.0992 1920 330 1.0530 ]30 1.96>0 1ll0 0.916) 1530 0.0299 19]0 340 3.1 J20 ]90 1.96]0 1390 0.9295 1540 0.019] 1940 350 1.2939 ]50 1.96>0 1150 0.>921 1550 0.013] 1950 360 1.2905 >60 1.96>0 1160 0 A609 1560 0.0090 3960 3]0 1.J386 J]0 1.96>0 11J0 0.]956 15J0 0.0061 19]0 ]00 1.J 55] >BO 1.96]0 1180 O.J956 1500 0.0092 1900 ]90 1.39>0 ]90 1.96>0 1190 0.8058 1590 0.0029 1990 900 1.]912 800 1.96>0 1200 0.000> 1600 0.0020 2000 2.26 ac-ft DESIGN RUNOFF I cfel 0.0019 o.aalo o.oa9> o.a6as o.oao3 0.0002 0.0002 0.0001 5/8/06 3:37:36 pm Skillings Connolly, Inc page 12 THE HUTCH SC 06099 ______________________________________ __________________________________________________________________ DETAIL HYDROGRAPH SUMMARY HYDROGRAPH No. Peak runoff: TIME -EBI GN TIME RUNOFF (min) (cfa) (min) 410 30 20 920 30 930 90 990 50 950 60 960 ]0 4]0 80 980 90 990 100 0.0001 500 110 0.0009 510 lzo o.oB29 s2o 1]0 0.005] 530 190 0.0092 s90 lsB a.an9 sm 160 0.01]] s60 v9 o.ozv no 300 0.0255 500 190 0.0290 590 200 0,0323 600 uB a.m sz 618 220 0.0300 620 no o.o4os 630 290 0.0928 690 250 0.0451 650 260 0.0981 660 280 0.0569 680 290 O.OSBe 690 300 0.061] 200 ]30 0.0632 ]10 RO 0.0699 230 330 O.O B2s IDO 390 0.0930 ]90 350 0.0996 250 360 0.1092 ]60 no oaoe6 no ]80 0.1104 ]00 390 0.1100 ]90 400 0.1092 000 13 0 -ESI GN RUNOFF f=£a) 0.1101 0.1109 0.1118 0.1311 0.1]91 0,2090 0.2556 0 .3306 O.J089 0.]853 a .3 z4e O.z231 0.2940 0.2214 0.2029 0.1931 0.1]1] 0.1562 0.1489 0.1948 O.lUO 0.1910 0.13]6 0.13s5 0.1398 0.3399 0.1230 0.125] a.lzal 0.11]] 0 .136J O.llsi 0,1158 0.1162 0.1166 o.un 0.11]9 O.11Bs 0.1159 3889 T I103 Imro) 810 ezo 830 840 850 860 B]0 080 890 908 910 9zo 930 940 950 960 920 980 990 1000 1010 1030 1030 1040 1050 1060 lO BO 1090 aloo 1110 1120 11]0 3198 1160 1160 11]a 11Bo 1190 1200 cfs DESIGN RUNOFF Icfa) 0.10]s o.lolo 0.09]8 a.o9n 0.099"1 0.0960 0.1004 0.109] 0.106] o.loeB 0.1099 8.110z 0.1110 0.1119 0,1129 0.1130 0.1138 0.10]9 0.0991 O .O B]6 0.0]]5 0.0 ]3s 0.0]13 0.0]39 0.0825 0.0890 0.0968 a.o982 0.0980 0.0991 0.090] 0.09]0 0.0981 0.0893 0.0811 O.oeso O .OB S2 0.0866 o.oe]o Tot TIME Imin) 1210 lzzo 1230 1290 1250 1260 12]0 3280 1290 1300 1310 13zo ll30 ll90 Ds0 1360 13]0 1380 1390 1400 1410 1920 1930 1990 1450 1460 1980 1990 lsaa 1510 1520 15J0 3540 1550 1660 lsio 1500 3690 16oa al Vol: -ESIGN TIME RUNOFF Ic£s) Imin O.OB4J 1610 0.00]8 1620 0.0802 1630 0.0882 3640 0,088] 1660 0.0090 1660 O.OB 90 16]0 0.0895 1680 0.009] 1690 0.009] 1]00 0.0902 1]10 o.o9a9 nzo 0.0904 1]30 O.OB89 1]90 0.003] 1]50 0.0]99 1]60 0.02]5 1]]0 o.oi61 v0a 0.0]55 1]90 0.0298 1800 0.0295 1010 0.0296 102a 0.0 ]9J 3830 0.0]9J 184C 0.0296 185L 0.0659 186[ 0.049) 16 ]( 0.02]9 10 B( 0.0185 1B 9[ 0.0120 190( 0.0080 191[ 0.0053 192( 0.0035 193[ 0.0024 194! 0.0016 195f 0.0011 196( 0.0008 19 ]{ a.ams 19e{ 0.0009 1991 B.BBO3 zm{ 0.20 ac-ft DSS IGN RUNOFF (cf e) 0,0002 O.oool 5/8/06 3:37:36 pm Skillings Connolly, Inc page 13 THE HUTCH SC 06099 DETAIL HYDROGRAPH SUMMARY HYDROGRAPH No. Peak runoff: TIME DESIGN TIME RUNOFF (minl (cfa) (min) 30 410 20 920 30 430 90 940 s0 0.0011 450 60 0.0060 960 t0 0.0151 4]0 00 O.OJ00 980 90 0.0516 490 100 0.0]30 s00 110 0.0932 510 lzo a.uo3 szo 130 0.1248 sJ0 140 0.1409 590 150 0.1603 550 160 0.1]J1 560 1]0 0.1091 5]0 180 0.1991 580 190 0.20]] 590 200 0.2190 600 210 0.2196 610 220 0.2298 620 230 0.2209 630 290 0.2320 690 250 0.2355 650 260 0.2929 660 2]0 0.255') 6]O 280 0.2661 680 290 0.2]30 690 300 0.2]]9 ]00 310 0.2009 ]30 ]20 O.JO50 ]20 330 0.3566 ]30 390 0.402s ]40 3so 9.4343 ]so 360 0.4616 ]60 3]0 0.4090 ]]0 ]80 0.9999 ]00 390 0.5058 ]90 400 0.5119 000 14 0 DEEIGN RUNOFF (cfa) 0.5212 0.92"1 O.s995 0.6939 0.0610 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 9260 TIME (mm) 910 020 030 840 960 8]0 080 090 900 910 920 9]0 990 950 960 9]0 900 990 1000 lalo 1020 1030 1040 3050 1060 1000 1090 1300 3110 l lzo 11]0 1190 use 1360 11]0 1190 1190 1200 cfs DESIGN RUNOFF (cfa) 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0.9260 0,9260 a.sz9s o.se o3 0.5]09 0.5]90 O.s]99 0.5090 O.s899 0.506] 0.5091 0.5606 0.4940 0.9409 0.9089 0.3059 O.3]2s 0.3019 0.4201 0.4536 0.9869 0.9960 0.9931 0.9]40 0.9584 0.9063 0.9910 o.a26e 0.9103 0.4260 0.925"1 0.4305 0.9321 TOt TIME ImIN 1230 1220 1D0 1290 1250 1260 12]0 1290 1290 1300 1310 1]20 1330 1390 13 s0 1]60 13"10 1380 1390 1900 1910 1420 1930 1990 1450 1960 1980 1990 1500 1510 l sao 15]0 1 s90 lsso 1560 15]0 1500 1s90 1600 al vol: D65I Q1 TItS RUNOFF lcfa) Irvin 0 9326 1610 0.4396 1620 0.9355 1610 0.4353 1690 0 .9J6B 1650 0 .9]]s 1660 0.93]0 16]0 0.4395 1600 0.4390 3690 0.4385 1]00 0.9]99 1]10 0.9904 1]20 0.9399 1430 0.9304 1]90 0.908] 1]s0 0.3900 1]60 O.J]81 1]]0 0.]]03 1]00 0. 3fi 64 1]90 0.3621 1900 0.3600 1810 0.3596 382C O.J5]B 10JC O.JS]2 184L 0.35]9 105C 0.316] 1861 0.1452 1BB[ 0.0996 189[ 0.06]1 190[ 0.0961 191( 0.0316 192( 0.0219 193( 0.0152 3941 o. om6 19so 0.00]9 1961 0.0052 19J( 0,00]6 1901 0.0026 1991 0.0018 2001 1.08 ac-ft DESIGN RUNOFF Icfal 0.0013 0.0009 0.0006 0.0009 0.0003 6.ooaz 0.0002 9.0001 5/8/06 3:37:36 pm Skillings Connolly, Inc page 14 THE HUTCH SC 06099 _____________________________ ____________________________________________________________ STAGE STORAGE TABLE CUSTOM STORAGE ID No. S1 Description: ROCK GALLERY STAG6 a----SROPAGE----> STAGE < ----6TOEAGE----> STAGE <----OTOPAGS----> BTAG6 ~----STORAGE----> (f U --- cf--- - -ACFC )f [ ) - --cf-- - -Ao-FC (f [) -- -cf--- - -AC-F[- (f [) --- cf--- --AC FC 330. 00 0.0000 0.0000 331. 10 3886 0.0]08 3J2. 20 6ll1 0.19ll 333. 30 925] 0.2125 3]0. 10 200.50 0.0064 331 .20 3366 0.0]]3 332. J0 6952 0.1981 333. 40 953] 0.2109 330. 20 561.00 0.0129 331 .30 ]64] O.O B3] 332. 90 6]32 0.1595 333. 50 9818 0.2259 3JO. J0 841.50 0.019] 331 .40 392] 0.0902 332. 50 ]013 0.1610 33]. 60 10098 0.2]18 3]O. gO 1122 0.0258 331 .50 9200 0.0966 3]2. 60 ]29J 0.16]4 ]D. ]0 10319 0.230] 330. 50 1903 0.0322 ]31 .60 9908 0.1030 332. >0 95]9 0.1]39 ]D. BO 10659 0.249] ]30. 60 1683 0.0386 331 .]0 9]69 0.1095 332. BO ]859 O.1B 0] J33. 90 10990 0.2511 330. 90 1969 0.0951 331 .80 5049 0.1159 3]2. 90 01]5 0.186] 339. 00 11220 0.25]6 330. 80 2249 0.0515 3]1 .90 930 0.1223 333. 00 8915 0.19]2 330. 90 245 0.0500 J32 .00 56ID 0.1200 33]. 10 0696 0.1996 331. 00 2005 0.0649 332 .30 SB91 0.1352 333. 20 09]6 0.2061 5/8/06 3:37:36 pm Skillings Connolly, Inc page 15 THE HUTCH SC 06099 STAGE STORAGE TABLE CUSTOM STORAGE ID No. S2 Description: ROCK GALLERY STAGE a----STORAGE----a BTAGE a---- STOPAGE----> GTAGE a----STOPAGE----a STAGE a----STORAGE----> (E C) ---cf--- - -AC-F[- If[) ---cf --- -AC-FC If [) --- cf--- --AC FO If t) --- cf--- --AC-FC- J 33 .00 0.0000 0.0000 D4. 30 1452 0.0333 3]5. 20 2909 0.066] 336. 30 4356 0.1000 333 .10 132.00 0.0030 3]4. 20 1509 0.0364 335. 30 30J6 0.069] 336. 90 4408 0.1030 333 .20 264.00 0.0063 ]]9 .30 1]16 0.0399 335. 40 3360 0.0]2"/ 336. 50 9620 0.1061 333 .30 J96.00 0.0091 334. 90 1898 0.0929 335. 50 ]]00 0.0]50 336. 60 4"!52 0,1091 3]] .q0 528.00 0.0131 ]]4. 50 1980 0.0955 335. 60 ]9J2 O.OpBB 336. ]0 4089 0.1121 333 .50 660.00 0.0152 ]]9. 60 2112 0.0985 335. ]0 3569 O.OB1B 336. 00 5016 0.1152 ]33 .60 ]92.00 0.0182 339. ]0 2299 0.0515 335. 80 ]696 0.0848 336. 90 5198 0.1182 333 .]0 939.00 0.0212 339 .80 2]]6 0.0595 ]]5. 90 ]020 0.00"19 33]. 00 5280 0.1212 3]] .BO 1056 0.0242 339 .90 2508 0.05]6 JJ6. 00 ]960 0.0909 333 .90 1188 0.0293 335 .00 2690 0.0606 J]6. 10 9092 0.09]9 334 .00 1J20 0.0]03 335 .10 2]]2 0.06J6 J]6. 20 9224 0.0970 5/8/06 3:37:36 pm Skillings Connolly, Inc page 16 THE HUTCH SC 06099 STAGE DISCHARGE TABLE DISCHARGE LIST ID No. D1 Description: INFILTRATION STAGE o--DISCHARGE--- a STAG6 <--DISCHARGE---a STAGE a--OISCHARGS---~ ETAGE c--DISCNARGS---> (f [) -cf~ (fe ) -cfs fEq -cfo (f t) -cfs 330. 00 1.96]0 JJ1. 30 1.96]0 332. 20 1.96]0 333. 30 3.96]0 330. 10 1.96]0 331. 20 1.96]0 332 .30 1.96]0 333. 90 1.96]0 330. 20 1.96]0 331. ]0 1.96]0 332 .90 1.96]0 3]3. 50 1.96]0 330. 30 1.96]0 331. 40 1.96]0 332. 50 1.96]0 3J3. 60 1.96]0 3J0. 90 1.96]0 J31. 50 1.96]0 332 .60 1.96]0 333. ]0 1.96]0 330. 50 1.96]0 JJ1. 60 1.96]0 332 .]0 1.96]0 333. 80 1.96]0 3J0. 60 1.96]0 331. ]0 1.96]0 3J2 .BO 1.96]0 ]D . 90 1. 96 ]O 330. ]0 1.96]0 331 .80 1.96]0 332 .90 1.96]0 JJ9. 00 1.96]0 330. 80 1. 96 ]O 331 .90 1.96]0 333 .00 1.96]0 ]]0. 90 1.96]0 332 .00 1.96]0 333 .10 1.96]0 ]31. 00 1.96]0 332 .10 y.96 ]0 33J .2O 1.96]0 5/8/06 3:37:36 pm Skillings Connolly, Inc page 17 THE HUTCH SC 06099 STAGE DISCHARGE TABLE DISCHARGE LIST ID No. D2 Description: INFILTRATION STAGS c--DISCHARGE---~ STAGE c--DISCHARGE---a STAGE c--DISCHARGE---> STAGE c--DISCHARGE---a (f [ ) -cfs (f q -cfs (f[) -cfs (f[) -cfs 333. 00 0.9260 ]39. 10 0.9260 -5. 20 0.9260 336. ]0 0.9260 ]JJ. 30 0.9260 334. 20 0.9260 ]35. 30 0.9260 JJ6. 90 0.9260 ]]3. 20 0.9260 339. ]0 0.9260 ]35 .90 0.9260 ]]6. 50 0.9260 ID3. J0 0.9260 3]4. 90 0.9260 335. 50 0.9260 336. 60 0.9260 J33. g0 0.9260 JJ4. 50 0.9260 335 .60 0.92fi0 336. ")0 0.9260 333. 50 0.9260 3]9. 60 0.9260 339 .70 0.9260 336. 80 0.9260 333 .60 0.9260 ID9. ]0 0.9260 3]5 .00 0.9260 3J6 . 90 0.9260 3]J .]0 0.9260 3]9. 00 0.9260 3]5 .90 0.9260 JJ] .00 0.9260 3JJ .00 0.9260 339. 90 0.9260 JJ6 .00 0.9260 JJJ .90 0.9260 335. 00 0.9260 ]]6 .10 0.9260 3]9 .00 0.9260 335. 10 0.9260 2]6 .20 0.9260 5/8/06 3:37:37 pm Skillings Connolly, Inc page 18 THE HUTCH SC 06099 LEVEL POOL TABLE SUMMARY M1LITCH INFLJW -STO- -D IS- <-PEAR-> OUTFIAW STORAGE c- -------06E CRI PLION------ --~ {c f e) (cf ~) --i d- --i tl- c-6 iAGEO id Icf e) VOL (cf) A 6 MO STORM EVEN'C O 00 1 19 SS D1 IDO 10 11 1.16 280 50 c£ A 100 YA STOEM EVENT ...... ... 0.00 4.05 S1 DI ]]].60 12 1.9] 10096 .]9 cf B 6 MJ BTORM EVENI ........ ... 0.00 0.90 52 D2 ]3].10 13 0.]9 132 .00 cf B 100 YR ETORM EVQI'f ...... ... 0.00 2.14 E2 -2 3]6.36 19 0.93 99J2 .91 c£ APPENDIX C -Supporting Data Soils Data SCS Soil Description SHILLINGS CONNOLLY, INC. 7 Velm Property Development LLC Hydrology Report Thurston Co'.: ntv. Washinc;on Inciuded areas make up about 10 percent of the total acreage. Permeabllny is moderately rapid in the Spana soil A ~allable water czpacny is moderate. Effective roof g de th is 20 to 40 Inches- A seasonal high water 1 le is at a depth of about 12 to 36 Inches from Novem r to April. Runoff is slow, and the hazard of water er sion is slight. Mos areas are used as hayland and pastu .This unit is s fled to hay and pasture. The main li nations are the s asonal high water table and the oderate available ater capacity. Proper stocking r tes, pasture rotation, an restricted grazing during we periods help to keep the asture in good condition a protect the soiNrom erns n. Rotation grazing help to maintain the quality of fora .Periodic mowing het s to maintain uniform growth, iscourages selectiv grazing, and controls weeds. most years irriga on is needed for maximum product n. Sprinkler irri lion is the best method of applying water. The a unt of water applied should be sufficient wet the ro t zone but small enough to minimize t e leachin of plant nutrients. A few areas are us as w Bland. On the basis of a 100-year site curve, th esti led site index for Douglas-fir is 144. On th b sis of a 50-year site curve, it is 110. The estimated g ~ah rate of an unmanaged, even-aced stand of Douel -#Ir Is 150 cubic feet per acre per year at 60 year o age. The main iimitation a ecti the harvesting of timber is the muddiness taus d by s asonal wetness. Use of wheeled and tracked quipmen when the soil is wet results in ruts ands compacti n. Unsurfaced roads and skid trails are s ft and can b impassable when wet. Logging road require suitabl surfacing material for year-round us .Rounded pebbl sand cobbles for road consiructio are re$dily availab on this unit. The seasonal high Ater fable limits the u e of equipment to dry periods. D' to rbance of the protect e layer of duff can be mini zed by the careful use of heeled and tracked equi ment. Seedlin establishment is the main con ern in the productio of timber. Reforestation can be accompli hed by planting Douglas-fir seedli s. It the stand I hides seed trees, natural reforestati by red alder curs periodically in culover areas. The easonal high Ater table inhibits root respiration and ih results ins e seedling mortality. When openings are ode in the anopy, invading brushy plants can prevent t es ablishmenl of planted Douglas-fir seedlings. Common forest understory plants are cascade regon-grape, salal, vine maple, western brackenfer , and Oregon white oak 89 nis ma ass Illw 110-Spanaway gravelly sandy loam, 0 to 3 percent slopes. This very deep, somewhat excessively drained soil is on terraces. It formed in glacial outwash and volcanic ash. The native vegetation is mainly grasses, ferns. and a few conifers. Elevation is 100 to 400 feet. The average annual precipitation is 45 to 55 inches, the average annual air temperature is about 51 degrees F, and the average frost-free period is 150 to 200 days. Typically, the surface layer is black gravelly sandy loam about 15 inches thick. The subsoil is dark yellowish brown very gravelly loam about 5 inches thick. The substratum to a depth of 60 inches or more is dark yellowish brown extremely gravelly sand. Included in this unit are small areas of Alderwood soils on till plains; Everett, Indianola, and Nisqually soils on outwash terraces; and Spana soils in depressions. Also included are small areas of Spanaway soils that have a stony sandy loam surface layer and small areas of Spanaway gravelly sandy loam that have slopes of 3 to 15 percent. Included areas make up about 20 percent of the total acreage. - Permeability is moderately rapid in the subsoil of the Spanaway soil and very rapid in the substratum. Available water capacity is low. Effective rooting depth is 60 inches or more. Runoff is slow, and the hazard of water erosion is slight. This unit is used mainly as hayland, pasture, or cropland, as a site for homes, or as a source of gravel. It is also used as woodland. The main limitation affecting hay and pasture is the low available water capacity. Proper grazing practices, weed control, and fertilizer are needed to ensure maximum quality of forage. Rotation grazing helps to maintain the quality of forage. Periodic mowing helps [o maintain uniform growth, discourages selective grazing, antl controls weeds. Animal manure can be applied periodically during the growing season. Areas that receive heavy applications should be harrowed at least once a year. In summer, irrigation is needed for maximum production of most forage crops. Sprinkler irrigation is the best method of applying water. The amount of water applied should be sufficient [o wet the root zone but small enough to minimize the leaching of plant nutrients. This unit is suited to crops. Wheat, oats, strawberries, raspberries, blackberries, and sweet corn are commonly grown. The main limitation is the low available water capacity. In summer, irrigation is needed for maximum production of most crops. 90 Sprinklers can be used, but a slow application rate is needed to minimize runoff. The amount of water applied should be sufficient to wet the root zone but small enough to minimize the leaching of plant nutrients. The application rate should be adjusted to the available water capacity, the water intake rate, and the needs of the crop: Animal manure can be applied periodically during the growing season. Areas that receive heavy applications should be harrowed at least once a year. This unit is well suited to homesites. Pebbles and cobbles should he removed, particularly in areas used for lawns. In summer, irrigation is needed for lawn grasses. shrubs, vines, shade trees, and ornamental trees. Mulch, fertilizer, and Irrigation are needed to establish lawn grasses and other small-seeded plants. The main limitation affecting septic tank absorption fields is a poor filtering capacity, If the density of housing is moderate or high, community sewage systems are needed to prevent the contamination of wat=_r supplies caused by seepage from onsite sewage disposal systems. Cutbanks are not stable and are subject to sloughing. Douglas-fir is the main woodland species on this unit. Among the trees of limited extent are Oregon white oak, lodgepole pine. and red alder. Douglas-fir and Scotch pine are drown on Christmas tree pL-ntations. On the basis of a 100-year sae curve, the mean site index for Douclas-fir Is 140- On the bads of a 50-year site curve, it is 108. The hiohest average growth rateof an unmanaged, even-aged stand of Douglas-fir is 145 cubic feet per acre per year at 65 years of age. This soil is suited to year-round logging. Unsurfaced roads and skid trails are slippery when wet. Logging roads require suitable surtacing material for year-round use. Rounded pebbles and cobbles for road construction are readily available on this unit. Disturbance of the protective layer of duff can be minimized by the careful use of wheeled and tracked equipment. Seedling establishment and seetlling mortality are the main concerns in the production of timber. Reforestation can be accomplished by planting Douglas-fir seedlings. If the stand includes seed trees, natural reforestation by Douglas-fir, Oregon white oak, and lodgepole pine occurs periodically in cutover areas. Droughtiness in the surface layer reduces the seedling survival rate. When openings are made in the canopy. invatling brushy plants can delay the establishment of planted Douglas- fir seedlings. Common forest understory plants are cascade Oregon-grape, salal, western brackenfern, western swordfern, Indian plum, and Scotch-broom. Soil Survey This map unit is in capability su bclzss IVs. 111-Spanaway gravelly sandy loam, 3 to 15 p rcent slopes. This very deep, somewhat excessiv dr ned soil is on terraces. It formed in glacial outw h and volcanic ash. The native vegetation is mainly gras s, ferns, and a few conifers. Elevation is 10 [o 400 f t. The average annual precipitation is 45 55 inches, the average annual air temperature is a out 51 degrees F, and the average frost-free period is 150 to 200 days Typical ,the surface layer is black gravel sandy loam about 15 inches thick. The subsoil is ark yellowish br wn very gravelly sandy loam bout 5 inches thick. he substratum to a depth 60 inches or more is dark y Ilowish brown extremely ravelly sand. Included in t is unit are small areas f Aldenvood soils on till plain and Everett, Indian a, and Nisqually soils on terraces. Iso included are all areas of Spanaway soils th t have a stony s ndy loam surface layer and small are s of Spanawa gravelly sandy loam that have slopes of to 3 percen .Included areas make up about 20 percent [he total creage. Permeability is mod rately r id in the subsoil of the Spanaway soil and ve rapid n [he substratum. Available water capacity ~s to .Effective rooting depth is 60 inches or more. Ru is slow, and the hazard of water erosion is slight. This unit is used main) hayland or pasture, as a site for homes, or as a s urc of gravel. It is also used as woodland. The main limitation ffecling hay and pasture is the low available water c pacify dur g [he growing season. Proper grazing prat ces, weed c nVOI, and fertilizer are needed to ensure aximum qualit of forage. Rotation grazing helps to aintain the quoit of forage. Periodic mowing helps to aintain uniform g wth, discourages selective grazin ,and controls weed Animal manure can be applie periodically during the rowing season. Areas that re eive heavy applications s ould be harrowed at east once a year. In summ r, irrigation is needed for aximum production of most rage crops. Sprinkler ~ rigation is the best method of a plying water. The am nt of water applied should be su -cient to wet the rod zone but small enough to minimize e leaching of pia nutrients. Th~ unit is suited to homesites. The main li nation is (h slope. Cutbanks are not stable and are s bled to slo ghing. A plant cover can be established and m intained through proper fertilizing, seeding. m thing, d shaping of the slopes. Pebbles and cobbles s ould e removed, particularly in areas used for lawns. In Thurston County. Washington sr, Irrigation is needed for lawn grasses, shrubsJJJJ shade trees, and ornamental trees. Mulch, ¢r, and irrigation are needed to establish law s and other small-seeded plants. Topsoil ca be tied and used to reclaim areas disturbed d nog The gin limitation affecting septic tank ohs rption fields is poor filtering capacity in the su bstr um. If the density of ousing is moderate or high, tom unity sewage sy ems are needed to prevent th contaminatio of water supplies caused b seepage from onsite s age disposal systems. T e slope hinders the ins Ration of the absorptio fields. Absorption lines hould be installed o the contour. Douglas-fir is t main woodland pecies on this unit. Among the trees o limited extent e Oregon white oak, lodgepole pine, and ed alder. Do gigs-fir and Scotch pine are grown on Ch istmas tre plantations. On the basis of a 100-year sit curve, a mean site index for Douglas-fir is 140. On t ba of a 50-year site curve, it is 108. The highest ave g growth rate of an unmanaged, even-aged st dot Douglas-fir is 145 cubic feet per acre per ye r t 65 years of age. This soil is suited toy ar-r and logging. Unsurfaced roads and skid trails ar slippe when wet. Logging roads require suitable urfacing aterlal for year-round use. Rounded pehbl and cobbl s for road - construction are re ily available this unit. Disturbance of the rotective layer duff can be minimized by the areful use o' whe ed and tracked equipment. Seedling es' blishment and seedling ortality are the main tooter in the production of timbe Reforestation can be act pushed by planting Douglas- it seedlings. If the stan includes seed trees, natural ref restation of cutover a eas by Oregon white oak and lodg pole pine occurs i frequently. Droughtiness in the surta layer reduce the seedling survival rate. When openi s are made in the canopy, invading brushy plants can elay the stablishment of planted Douglas-fir seedlings. ommon forest understory plants are cascade O egon-grape, salal, western brackenfern, western ordfern, Indian plum, and Scotch-broom. This map unit is in capability subclass IVs. 112-Spanaway stony sandy loam, 0 to 3 percent slopes. This very deep, somewhat excessively drained soil is on terraces. It formed in glacial ou[wash and volcanic ash. The native vegetation is mainly grasses, ferns, and a few conifers. Elevation is 200 to 400 fee[. The average annual precipitation is 40 to 50 inches, the average annual air temperature is about 51 degrees F, and the average frost-free period is 150 to 200 days. Typically, the surface layer is black stony sandy loam about i6 inches thick. The subsoil is very dark brown gravelly sandy loam about 6 inches thick. The substratum to a depth of 60 inches or more is grayish brown extremely gravelly sand. Includetl in this unit are small areas of Alderwood soils on till plains, Baldhlll soils on terminal moraines, and Everett. Indianola, and Nisqually soils on terraces. Also included are small areas of Spanaway soils that have a gravelly sandy loam surface layer and small areas of Spanaway stony sandy loam that have slopes of 3 to 16 percent. Included areas make up about 16 percent of the total acreage. Permeability is moderately rapid in the subsoil of the Spanaway soil and very rapid in the substratum. Available water capacity is low. Effective rooting depth is 60 inches or more. Runoff is slow, and the hazard of water erosion is slight. This unit is used mainly for hayland, pasture, or homesites. The main limitations affecting hay and pasture are the low available water capacity and the stones on the surface. Proper grazing practices, weed control, and fertilizer are needed to ensure maximum quality of forage. Rotation grazing helps to maintain the quality of the forage. Because of the surface stones, spreading animal manure, mowing, and seeding are difficult In summer, irrigation is needed for maximum production of most forage crops. Sprinkler irrigation is the best method of applying water. The amount of water applied should be sufficient to wet the root zone but small enough to minimize the leaching of plant nutrients. This unit is well suited [o homesites. Pebhles, cobbles, and stones should be removed, particularly in areas used for lawns. In summer, irrigation is needed for lawn grasses, shrubs, vines, shade trees, and ornamental trees. Mulch, fertilizer, and irrigation are needed to establish lawn grasses and other small- seeded plants. Cutbanks are not stable and are subject to sloughing. The main limitation affecting septic tank ahsorpiion fields is a poor filtering capacity in the substratum. If the density of housing is moderate or high, community sewage systems are needed to prevent the contamination of water supplies caused by seepage from onsite sewage disposal systems. This map unit is in capability subclass IVs. 113- p stony sandy to percent slopes. This very tl excessively drained soil i ces. It formed in glacial ou d t6a Spanaway Series The Spanaway series consists of very deep. somewhat excessively drained sails on terraces. These soils formed in glacial outwash and volcanic ash. Slope is 0 to 16 percent. Elevation is 100 fo 400 feet. The average annual precipitation is 40 to 0'S inches. the average znnual air temperature Is about 51 degrees F, and the average frost-free season is 150 to 200 days. These soils are sandy-skeletal, mixed, mesic Andic Xerumbrepts. Typical pedon of Spanaway gravelly sandy loam, 0 to 3 percent slopes. 4 miles southeast of Lacey; about 250 feet west and 400 feet south of the northeast corner of sea 25. T. 36 N.. R. 1 W. A-0 to 15 Inches'. black (10VR 2/1) gravelly sandy loam. very dark grayish brown (10YR 3/2) dry', weak fine granular structure: loose, very friable, nonsticky and nonplastic: many fine. medium, and coarse roots: 25 percent pebbles: strongly acid: clear smooth boundary. Bw-15 to 20 inches; dark yellowish brown (10YR 3/4) very gravelly sandy loam, light olive brown (2.SY 5:'4) dry: weak fine subangular blocky structure; loose. very friable, nonsticky and nonplastic, many fine, medium. and coarse roots', 55 percent pebbles: metlium acid, clear smooth boundary. C-20 to 60 inches', tlark yellowish brown (10VR 414) extremely gravelly sand. yellowish brown (10YR 5;4) dry; single grained; loose; few fine roots; 80 percent pehbles, 10 percent cobbles; slightly acid. The thickness of the solum ranges from 15 to 26 inches. The content of coarse fragments in the control section ranges from 50 to~85 percent. The weighted average texture of this section is very gravelly sand or extremely gravelly sand. The umbric epipedon is 10 to 20 inches thick. The A horizon has hue of 10YR or 7.SYR, value of 3 or 4 when dry, and chroma of 1 or 2 when moist or dry. It is medium acid or strongly acid. The Bw horizon has value of 4 or 6 when dry and 3 or 4 when moist. Il is very gravelly sandy loam, very gravelly loam, or extremely gravelly sandy loam. The C horizon has hue of 10YR or 2.SV, value of 5 or 6 when dry and 4 or 5 when moist, and chroma of 3 or 4 when dry or moist. II is extremely gravelly sand or extremely gravelly loamy sand and is slightly acid or neutral. Sulta The Sultan se eo mo Soil Survey tlrained soils on flood plains. These soils formed it ium. Slope is 0 to 3 percent. Elevation is 20 to 75 The average annual precipitation is 40 to 50 ,s, the average annual air temperature is about 0 ees F, and the average frost-free season is 75 to soils are fine-silty, mixed, nonacid, 200 Aquic erofluvents. Typi I pedon of Sultan silt loam, 7 miles e t of Lacey', a out 1,000 feet east and 1,975 feet rth of the southwes corner of sec. 16, T. 18 N., R. 1 Ap-0 to 7 chest dark yellowish brown (1 YR 3/4) silt loam, br wn (tOYR Sri) dry; moderat fine and medium g anular structure; slightly h rd, very friable. slag fly sticky and slightly pl slit; many fine, medium, an coarse roots; many ry fine and fine tubular pore ~ slightly acid; abrup smooth boundary. BA-7 to 20 inche ~ dark yellov silt loam, brown (10YR 6/3) medium subang ar blocky very triable, slight sticky a very fine, fine, and and fine tubular par boundary. Bw1-20 to 25 inches; d~ grayish hrown (2.SY prominent red (2.SYF and medium suban hard, very friable, is common fine and e and fine tuhular ore boundary. ash rown (10YR 4/4) dr moderate fine and ucture; silghtly hard, d slightly plastic; many roots; many very fine Ily acid; clear wavy mown (10YR 3/3) silt ;oam, dry; common fine mottles; moderate fine locky structure; slightly tacky and sllghUy plastic; i ots; common very fine gh y acid; gradual wavy Bw2-25 [0 45 in es; dark brow (tOYR 4!3) silt loam, light brownis gray (tOYR 6/2) ry; common medium pro anent red (25YR 5 B) mottles; moderate edium and coarse su angular blocky structure; lightly hard, very friabl slightly sticky and slag ly plastic; few very fine a fine roots; few very fin and fine tubular pores; slag fly acid; gradu wavy boundary. C-45 to 0 inches; grayish brown (10YR /2) silt loam, ligh gray (10YR 7/2) dry; common me 'um pr inen[ dark brown (7.SYR 4/4) mottl ;massive; sf Mly hard, very friable, slightly sticky a d slightly astic; slightly acid. ~7he soils are slightly acid or neutral in the a coon and range from slightly acid to strongly low a depth of 40 inches. Mottles that have e 3 or more are at a depth of more than 20 in< 26o Soil Survey THOLE 14.--ENGINEERING INDEX FROPERTIEE--Continued Classification ,Frag- Percentage passing Sail name and ,Depth', USDA texture '~Iments ~ sieve number-- ;Liquid ~ Plzs- map symbol i Unified ~ AASHTO ~ > 3 i limit i ticity ',Snches~ 4 l0 40 200 index In Pc[ Pct , , , i , - , , , , , , -~- 110, 833---------i 0-16iGravelly sandy ', GM, SM iA-1, A-2 i 0-5 ifs-85 'S0-]5 ,30-50 115-25 i 35-50 ~ NF-10 Spanaway i loam. X15-20~Very gravelly ii GM ',A-1, A-2 ', 0-10 135-55 ,25-50 ,15-45 X10-35 ~ 35-50 ~ NP-10 loam, very gravelly sandy loam, extremely gravelly sandy 1i loam. 20-60~Ex tremely iGP, GW iA-1 110-25 i2f-35 ,20-30 110-20 ~ 0-5 --- NP gravelly sand, extremely gravelly loamy sand. -~ 112, 333---------i 0-16~Stony sandy loam ,SM ,A-2 ' 5-20 i]0-90 ,60-BO ,40-50 i25-35 i 35-SD ~ NP-10 Spanaway 116-22 ,Very gravelly iGM ,A-1, A-2 ~ 0-10 ,35-55 i25-50 120-40 ,10-30 i 35-50 i NP-10 loam, very gravelly sandy loam, extremely gravelly sandy loam. 122-60~Extremely ,GP, GW iA-1 110-25 i25-35 '20-30 110-20 i 0-5 --- NP ~ gravelly sand, extremely gravelly loamy sand. , , , i , , , , , , 119*: , ~ , i , , ~ Spanaway--------~ 0-15~G: avelly sandy ,GM, SM ,A-1, A-2 i 0-5 153-85 ,50-]5 130-50115-25 i 35-50 ~ NF-30 loam. 115-20~Very gravelly 'GM ,A-1, A-2 i 0-10 ,35-55 '25-50 X15-46 ,10-35 ~ 35-50 ~ NP-10 loam, very gravelly sandy loam, eztremely gravelly sandy loam. X20-60~EZ treme ly ,GP, GW iA-1 ,30-25 i25-36 ,20-30 110-20 i 0-5 --- NR gravelly sand, ~• extremely gravelly loamy ~ sa d. , r i , i , i , Nisqually-------i 0-5 ,Loamy Eine sand ,SM iA-2 i 0 i 100 ~ 100 150-00 115-30 i --- i NP ~ 5-31iLOamy sand, loamyiSM iA-2 0 ~ lOD i 100 ,60-80 ,20-3D , --- NP ~ fine sand. 31-60 iLoamy Eine sand, ~iSP-SM, SM ,A-3, A-2 i 0 i 100 i 100 ~i66-05 i 5-20 , --- NP loamy sand, sand. 115--------------i 0-] ,Silt loam--------,ML ,A-4 i 0 i 100 i 100 i8D-90 ,70-60 i 20-30 i NP-5 Sultan i ]-60~Silt loam, silty iCL-ML, CL iA-4, A-6 , 0 i 100 ~ 100 195-100,00-90 ~ 25-35 ~ 5-15 clay loam. 116--------------. 0-0 Silt loam--------,ML, OL ,A-4 i 0 i 100 ~ 100 190-100 170-90 i 30-40 i NP-10 Tacoma ~ ]-50i5f1t loam, very ,ML ,A-9 0 ~ 100 i 100 i95-IOOiES-95 i 25-36 i NP-10 fine sandy loam. X50-60~6i1t loam, silty iCt ,A-6, A-] i 0 ~ 100 i 100 195-100190-1001 30-50 i 10-25 clay loam, clay. See footnote at end of table. Thur,:Dn County. Washington TABLE 15.--PHYSICAL AND CHEMICAL PROPERTIES OF THE SOILS--Continued Soil name and ,Depth, Clay ', Permeability Available Soil ~ Shrink-swell map symbol i i i ~ water capacity ,reaction, potential 27: 109--------------i 0-221 7-15 i 2.0-6.0 i 0.12-0 .14 15.6-6.0 iLOw------------10.241 5 1 5-15 Spa a ,22-26, 5-15 i 2.0-6.0 ~ 0.19-0 .1] 15.6-6.0 ,Low------------,0.1], ' 126-381 5-15 ~ 2.0-6.0 ~ 0.09-0 .12 ,5.6-6.0 ,Low------------10.101 ~ 3&-60, 2-5 ~ 6.0-20 , OAS-0 .08 15.6-6.0 ,Lox------------i0.05~ i i i i i i ~ i ~ 110,-F33---------i 0-15~ --- i 2.0-6.0 ~ 0.11-0 .13 15.1-6.0 ~LOx------------~O.15i 2 i 5-15 _ Hpanaway ,15-201 -- i 2.0-6.0 ~ 0.09-0 .12 ,5.1-6.5 ,Low------------10.101 ' 120-60, 0-5 ~ >20 ~ 0.03-0 .05 ,6.1-7.3 ,Low------------i0.02~ 112,-kkJ---------i 0-161 --- i 2.0-6.0 ~ 0.11-0 .13 X5.1-6.0 ~LOw------------'0.15 ~ 2 5-15 i 8panaway 116-22, --- i 2.0-6.0 i 0.09-0 .12 15.1-6.5 Low------------,0.10, i ' i 22-60, 0-5 i >20 i 0.03-0 .05 16.1-].3 ,Low------------, O. W, ~ 119*: 8panaway--------i 0-151 --- i 2.0-6.0 ~ 0.11-0 .13 15.1-6.0 iLOw------------~O.15i 2 1 5-15 15-201 -'- i 2.0-6.0 ~ 0.09-0 .12 ,5.1-6.5 iLOw------------10.101 20-601 0-5 ~ >20 i 0.03-0 .05 16.7-].3 ,Low------------, 0.@, ~ i Niscually-------. 0-5 ~ i 0-5 i i 2.0-6.0 i 0.09-0 .12 i ,5.6-6.5 i i i iLOw---------~--~0.20i i 5, 3-10 ~ 5-311 0-5 i 2.0-6.0 ~ 0.08-0 .12 15.6-6.5 ,Low------------i0.28~ ~ 31-601 0-5 ~ )20 ~ 0.04-0 .0] ,6.1-73 iLOw------------i0.24~ ~ 115--------------i 0-] ~ 15-20 ~ 0.6-2.0 ~ 0.18-0. 20 ,6.1-].3 iLOw------------,0.3 ], 5 ~ 5-10 Sultan i ]-601 20-30 ~ 0.6-2.0 ~ 0.18-0 .20 ,6.1-73 ~Pioderate-------,0.32, ~ 116-------------i 0-7 ', 5-18 ~ C.6-2.0 ~ 0.25-0 .35 13.6-5.5 iLOw------------,0.28, 5 i 10-20 Tacoma , 7-50; 5-18 ~ 0.2-0.6 ~ 0.20-0. 30 ,3.6-5.5 ,Law------------10.321 ' 50-50, 2G-50 ~ 0.2-0.6 ~ 0.19-0. 21 ,3.6-5.0 ,Moderate-------i0.32~ ~ 11], 118, 115----~ 0-11, 10-15. ~ -0.6-2.0 i 0.12-0. 14 ,5.1-6.0 ~LOw-----------~0.20i 2 i 5-10 Tenino ill-36, 10-15 ~ 0.6-2.0 ~ 0.12-0. 14 ,5.1-6.0 ,Low------------i 0.20, ~ 136-401 i --- i --- i ___ ~ ___ i i_______________i____i i ~ i 140-60, 2-10 ~ >20 ~ 0.06-0. 0] ,5.1-6.0 ,Low------------i 0.021 120--------------~ 0-11, --- ~ 0.6-2.0 , 0.25-0. 35 ,5.6-].3 ~LOw------------i0.28~ 5 ~ 3-10 Tisch ill-50, --- i 0.2-D.6 i 0.25-0. 35 ,5.6-].3 ,Low------------,0.28, 50-601 --- i 0.6-2.0 i 030-0. 40 15.6-].3 ,Low------------10.001 121, 122---------i 0-f0, --- ~ 0.6-2.0 i 0.25-0. 35 15.1-6.0 ,Low------------,0.24, 3 i 5-10 Vailton 110-15, --- i 0.6-2.0 i 0.25-0. 35 ,5.1-6.0 ,Low------------,0.24, 15-481 --- i 0.6-2.0 , 0.20-0. 30 ,5.1-6.0 ,Low------------,0.15, ~ ~ g8 i i i i ___ i i_______________~____i i i i ~ 123, 124---------i 0-11, 10-25 ~ 0.6-2.0 ~ 0.1]-0. 20 ,5.1-6.0 iLOw------------i0.32~ 5 i 5-10 Wilkes on ,11-4]i 25-35 ~ 0.6-2.0 ~ 0.12-0. 1] ,5.1-6.0 ,Moderate-------,0.20, 4]-60, 18-35 ~ 0.6-2.0 ~ 0.15-0. 20 15.1-6.0 iMOderate-------0.20 125. %eror[hen is ' 126, 12], 128----i 0-8 ~ --- ~ 2.C-6.0 ~ 0.25-0. 35 5.6-6.5 .Lax------------i032~ 5 ~ 3-9 Ye 1m i e-461 --- . 2.0-6.0 0.15-0. 25 ,5.6-6.5 ,Low------------,0.321 146-60'1 0-5 i 6.0-20 ~ 0.04-0. 09 ,5.6-6.5 ,Low------------,0.10, ~ * See description of the map unit Eor composition and behavior characteristics of the map unit Thurston County, lNZShingtOn Soil name and mop symbol 277 TABLE 16.--WATER FEATURES--Continued Flooding Hiqh water table Hydrologic group Frequency Duration ~ Months Depth Kind ~ I9onths : 100r 101 ________________i p Scamman 102, 103________________i B Schneider 109_____________________i C Sem iahmoo : : 105_____________________i p Shalcaz 306_____________________i D Shalcaz Variant 107, lOB----------------i D Skipopa 109_____________________i D Spana ~ uD,~r,~ uz, 1i3------~ a Spanaway : 119*: : : SPanawaY_______________i g 9 Y____________ Nis call --. 6 115_____________________i C Sultan 116_____________________i D Tacoma 117, 118, 119-----------i C Ten ino 120_________________~___i D Tisch 121, 122________________i 8 Vailton 123, lI9________________i B Wil kwon 125_____________________i C Xeror [hoots 126, 127, 12E----------i C Yelm Ft --- --- 0.5-1.6 liPerched : : : : : ___ ' ___ ' >6 0 i ___ --- --- i 1.5-3.0 iAppazent --- --- +1-0 iApparent : ~ ~ : i : ig----------i Nov-May ~ +1-0 iAPParent --- --- ~ 1.0-2.0 ~~Perched --- --- i 1.0-3.0 ~AppazenY : : : : : ___ ___ ~ )6.0 ~ ___ ___ : ___ i >6 0 i ___ : : : : ___ ' ___ ' )6 0 i ___ : : : : : ---------i Nov-Apr ~ 2.0-9.0 ,Apparent : i ~ : i : ---------~ Nov-Jun ~ +1-0 ~Appazent i : ~ ___ i ___ i )6.0 i ___ --- --- 0-1.0 ~Appazent ___ ___ )6.0 ___ : : : : : -- i --- i >6.0 i --- --- --- >2.0 iApparent --- : --- i 1.5-3.0 ~Appazenf * See description of the map unit Eor composition and behavior characteristics of the map mit. APPENDIX D - BMPs SK/LL/NGS CONNOLLY, INC. a Velm Property Development LLC Hytlmlogy Report THE HUTCH SOIL TEST HOLES April 2006 Test Hole 1 0" - 12" Loam 12" - 78" Brown Sandy Gravel w/ Cobbles 8" - 138" Gray Sandy Gravel w/ Cobbles Test Hole 2 0" - 30" Loam w/ Cobbles 30" - 96" Med Sand w/ Cobbles 96" - 126" Sandy Gravel Test Hole 3 0" - 30" Loam w/ Cobbles 30" - 78" Brown Med Sand w/ Cobbles 78" - 120" Gray Med Sand /Cobbles Test Hale 4 0-42" Loam w/ Cobbles 42" - 108" Brown Med Sand 108" - 144" Gray Sandy Gravel Test Hole 5 0"-28" Loam w/ Cobbles 28"-90" Brown Sandy Gravel w/ Cobbles 90"-128" Gray Sandy Gravel w/ Cobbles Test Hole 6 0" - 20" Loam 20" - 105" Brawn Med Sand Gravel w/ Cobbles Test Hole 7 0" - 30" Loam 30" - 96" Brown Med Sandy Gravel Test hole 8 0"-20" Loam w/ Cobbles 20"-75" Brown Sandy Gravel w/ Cobbles 75"-120" Gray Sandy Gravel w/ Cobbles Stormwater Program Guidance Manual Volume l1 PURPOSE Many products and practices commonly used in and around our houses are hazardous to both ourselves and the environment. The purpose of this chapter is to give alternatives, where possible, for those types of products and practices. There are two categories of BMPS in this chapter. The first category of BMPS includes "goad housekeeping" practices that everyone should use. The second category of BMPS deals with erosion and pollution control practices for people who raise large animals. RECOMMENDED POLLUTION CONTROL PRACTICES FOR HOMEOWNERS It has been said that the average home today contains more chemicals than the average chemical lab of .100 years ago. When many of these chemicals are used industrially, they can be subject to various health and safety standards; yet these same substances are used freely and often carelessly in homes across the nation. The BMPS in this section are divided into four categories: Household Hazardous Wastes, Pesticides, Remodeling, and Septic Maintenance. Each section includes information on available alternatives. Household hazardous wastes Many of the cleaning agents, solvents, polishes, etc. used commonly in the home are considered hazardous wastes. Theseproducts may be toxic, corrosive, reactive, flammable, and/or carcinogenic.. It is critical that these products are disposed of properly. A list of some common household hazardous wastes is presented in Table 1. In addition, many hazardous household chemicals persist for long periods of time in the environment. Manufacturers may truthfully state that a product is "biodegradable"; most products are biodegradable, but what is important is the r eat which they are broken down and the r uc they. are6roken down into. The term "hiodegradable" on its own is thus rather meaningless unless the product is rapidly degraded into harmless breakdown products. Residential Best Management Practices Stormwaier Program Guidance Manual Volume Il It is important to note here that the term "biodegradable" currently has no legal definition in this state. This means that any product can use this term according to the manufacturer's own definition. This definition may not be at all similar to the consumer's perception. Household oroduct manacement Buy only those detergents that contain little or no phosphorus. Phosphorus can cause algae blooms if it is washed into lakes, streams, bays ar from septic systems into ground water. Most detergents which are low or phosphate free are labeled as such. 2. Use only the manufacturer's suggested amount of any cleaner. More is not necessarily better. . 3. Products such as oven cleaner, floor wax, furniture polish, drain cleaners, and spot removers often contain chemicals that are toxic.. Buy the least toxic product available, and use anon-toxic substitute if one can be fountl. Ovens, for example can be cleaned by applying table salt to spills, then scrubbing with a solution of washing sodaand water. Table 2 lists some substitutes for commonly used household cleaners. If it is necessary to use a product that contains toxic chemicals, then use the product only as directed. Do not combine products, as they may become more dangerous when mixed (such as chlorine bleach and ammonia). Use protective clothing and rubber gloves. Contact the Hazardous Substance Hotline at 1-300-633-7585 if you have any Questions regarding how to dispose of a product or empty container. Many areas now have either hazardous waste collection days, or permanent facilities where residents can bring hazardous wastes. Call your county's environmental health department for further information. 4. Chemicals left over from such hobbies as photography era hazardous and should not be flushed down the sink. This is especially important if your home is hooked up to a septic system. Toxic chemicals can kill the bacteria in the tank that treat sewage. Residential Best Management Pracrices Stormwater Program Guidance Manual Volume ll 5. Buy toxic products in small quantities. If you cannot use all of the product, try to give it away instead of disposing of it. 6. Be sure that the contents of all containers are clearly marked. Common (not automobile) batteries are one of the worst sources of heavy metals found in landfills: Instead of throwing them away, dispose of them at a hazardous waste collection site. AUTOMOTIVE USAGE, CARE AND MAINTENANCE 1. Cars should be serviced regularly. Any leaky lines or valves should be replaced. Dumping oil, degreasers, antifreeze, and other automotive liquids into a stream or a storm drain is illecal. Do not dump them onto the ground because they will'end up in stormwater runoff once it rains. Do not use oil to reduce dust levels on unpaved areas. 2. If possible, recycle used oil and antifreeze. Keep them in separate containers. Call the Recycling Hotline at 1-B00-RECYCLE for the location of the nearest recycling center or call your local gas stations. 3. Wrap empty oil or antifreeze containers in several layers of newspaper, Yie securely and place in a covered trash can. Antifreeze is sweet-tasting, but poisonous to people, fish, pets and wildlife. 4. Sweep your driveway instead of/or before hosing it down. Many toxicants and heavy metals associated with automobiles can build up on driveway surfaces and be washed into local surface water when driveways are hosed down. 5. When washing vehicles, direct soapsuds onto the lawn or another vegetated area to keep the soap from washing into the local surface water. 6. Small spills of oil and other fluids can be absorbed by using materials such as kitty litter or sawdust. Wrap the used kitty litter and any contaminated soil in a plastic bag and then place it in the garbage. If a spill reaches surface water, you must notify the nearest regional office of the Department of Ecology: Residential Best Management Practices Stormwater Program Guidance Manual Volume /l Northwest Region -Redmond 867-7000 (24-hour) Southwest Region -Olympia 753-2353 124-hour) There are fines for failure to notify the appropriate agency when a spill occurs Deicing chemicals (most commonly salt) are often used on private sidewalks and driveways during cold winter weather. These chemicals can harm concrete less than three years in age, and burn vegetation. They are also corrosive to cars and other metal objects. Not only are the deicing chemicals pollutants, but the additives are often pollutants as well. Cyanide is formed from the breakdown of a common anti-caking agent used in deicing chemicals: Urea salts have been proposed as an alternative to other types of salt deicers, but great care must be used in applying them. These salts contain large quantities of nitrogen, which can severely burn plants if over-applied. ' The use of these chemicals should be minimized or avoided if possible. While deicing chemicals are more effective in removing snow from roads than are grits such as sand, they cause much worse pollution and if used at all should be used in moderation. SMALL BOAT USAGE, CARE AND MAINTENANCE In narrow creeks and coves boat wakes can contribute to shoreline erosion. To minimize erosion, boats should not produce wakes within 500 feet of shore. A speed greater than 6 knots can cause a wake with great erosive force. 2. When washing a boat, use low phosphate or phosphate free detergent. Using a brush and scrubbing the boat down after each use can minimize the need for washing. When possible, avoid stain-removing products as they are generallytoxic. Residential Best Management Practices S[ormwater Program Guidance Manual ' ; Volume tl Table 1 Hazardous Household Substances List Reoair and Remodelin 1. Adhesives, glues, cements. 2. Roof coatings, sealants. 3. Caulking and sealants. 4. Epoxy resins. ~ 5..Solvent-based paints. ~'~. 6. Solvents and thinners. 7. Paint removers and strippers. Cleaning Agents t. Oven cleaners 2. Degreasers and spot removers 3. Toilet, drain and septic tank cleaners I 4. Polishes, waxes and strippers 5. Deck, patio and chimney cleaners 6. Solvent cleaning fluids Pesticides t. Insecticides 2. Fungicides 3. Rodenticides 4. Molluscicides 5. Wood preservatives 6. Moss retardants 7. Herbicides 8. Fertilizers Auto,.BOat and Eouioment Maintenance 1. Batteries 2. Waxes and cleaners 3. Paints, solvents and thinners 4. Additives 5. Gasoline 6. Flushes 7. Auto repair materials 8. Motor oil 9. Diesel oil 10. Antifreeze Hobbv and Recreation 1. Paints, thinners and solvents 2. Chemicals-(photo and poo!1 3. Glues and cements 4. Inks and dyes 5. Glazes 6. Chemistry sets 7. Bottled gas 8. White gas 9. Charcoal starter fluid MiSCellane 1. Ammunition 2. Asbestos 3. Fireworks Source: Guidelines for Local Hazardous Waste Planning, Ecology, No. 87-78, 7987. Residential 5 Best Management Practices S[ormwater Program Guidance Manual lrolume 11 Table 2 Non-Toxic or Less Toxic Alternatives to Toxic Products Hazardous Product Alternative(s) Air fresheners Set out a dish of vinegar or simmer cinnamon and cloves or set out herbal bouquets or potpourri in open dishes or burn scented candles. .Bleach Borax or oxygen bleaches or reduce bleach by %, and add %. -'h C. baking soda, or let clothes dry in the sun. Brass polish - Worcestershire sauce. Chrome polish Apple cider vinegar or a paste of baking soda and water or a lemon peel. Coffee stains Moist salt paste. Coffee pot cleaner Vinegar. Copper cleaner Mix lemon juice and salt or use tomato catsup. Drain cleaner Use a plunger followed by '/: C. baking soda mixed in 'h C. vinegar. Let sit 15 minutes, pour down 2 qts. boiling water. Furniture polish Linseed, olive or almond oils or a mixture of 3 parts olive oil to 1 part white vinegar or a mixture of 1 Tbsp. lemon oil and 1 pint mineral oil. Garbage disposal deodorizer Used lemon rind or baking soda. Glass cleaner Mix 2 Tbsp. vinegar with 1 quart water. Residential g Best Management Practices Stormwater Program Guidance Manua! Volume 11 Grease remover Make a paste of borax on a damp cloth. Ink stain remover - Spray with leftover non-aerosol hairspray before washing. Laundry soap Borax, baking soda or washing soda. Linoleum floor cleaner 1 C. white vinegar in 2 gals. water. Mildew remover Equal parts vinegar and salt. ~,. Mothballs Cedar chips or blocks, or use dried tansy, lavender or peppercorns in drawers and closets. Oil spills Kitty litter, sawdust. Oil stain removal White chalk rubbed into the stain prior to washing. Over cleaner Pour lots of salt on fresh spills and scrape off after the oven cools. A. soda water solution will cut grease. Paint ammonia on spills with a paintbrush; then rinse off. Paint brush softener Hot vinegar. Paint/grease remover Wear gloves or use baby oil. Paint stripper Use mechanical sanding instead of chemical strippers. Pet odor removal Cider vinegar. Pitch or sap remover Butter, margarine or vegetable shortening. Porcelain stain remover Baking soda. i Residential ' - 7 Besi Management Practices Siormwater Program Guidance Manual Volume l! Refrigerator deodorizer Rug/carpet cleaner (general) Rug/carpet cleaner (spots) ~, Rust removal Rusty bolt remover Scorch mark remover Spot remover Scouring powder Silver polish Stainless steel polish 'i, Toilet bowl cleaner Tub and file cleaner Upholstery spot remover Water mark remover Water softener Open box of baking soda. Use asoap-based non-aerosol rug shampoo, vacuum when dry. Pour on club soda or sprinkle cornmeal or cornstarch on the rug, let sit at least 30 mins. then vacuum. Lemon juice plus salt plus sunlight. Carbonated beverage. Grated onion. Club soda, lemon juice or salt or rub with a cornstarch paste, brush off when dry. Baking soda or anon-chlorine scouring powder. Soak silver in warm water with 7 Tbsp. soda, 1 Tbsp. salt and a piece of aluminum foil. Mineral oil. Past of borax and lemon juice. '/. C. soda and %, C. white vinegar mixed with warm water. Club soda. Toothpaste. %. C. vinegar. Residential g Hest Management Practices i Sfdrmwaier Program Guidance Manual Vn/ume // Boat hulls may have been repainted with tributyltin (a paint) to prevent fouling. This type of paint is eMremely toxic to marine life. When scraping the boat bottom, catch the scrapings with a drop cloth. Compress the scrapings into as small a can as possible, label the can and turn it in to the nearest household hazardous waste collection center. Repaint the hull using acopper-based paint. Copper-based paints are less toxic (although not non-toxic) to marine life. PESTICIDES' AND FERTILIZERS Pesticides (such as insecticides and herbicides) and fertilizers are commonly used by homeowners in their quest for bigger, healthier plants. These chemicals are easily overused. Homeowners often do not know just how much fertilizer is necessary in their soil. Often, people assume that more is better. These chemicals are easily introduced into stormwater runoff and can cause algae blooms (fertilizers) or kill off aquatic organisms Ipesticidesl. Fertilizer management 1. Before fertilizing, test your soil. This can be easily done by using kits that are available, or through tests provided by the County Cooperative Extension office in your area. Use only the recommended amount of fertilizer. - 2. Use fertilizers that are appropriate for your area, and for fhe type of plants you are growing. Work the fertilizer into the soil directly around the plant's drip line. By incorporating the fertilizer into-the soil, there will be less likelihood of contaminated runoff. 3. Water before fertilizing. Water enough to dampen the ground thoroughly, but not enough to cause surface runoff. 4. Many soils can benefit from the use of organic fertilizers such as compost or peat. Not only do these substances add nutrients to soil, they also increase the porosity of the soil and increase its ability to hold water. ' As used here, the word pesticide can mean any herbicide, insecticide, rodenticide, miticide or other types of chemicals used in the same manner. Residential Best Management Practices Stormwater Program Guidance Manual Volume /l 5. Slow release fertilizers (which are generally resin-coated) can be used in addition to organic fertilizers. They are not mobile in the soil, and are only applied once, which saves work. Integrated nest manacement Rather than bringing out the sprayer whenever a pest infestation occurs in the garden, consider using Integrated Pest Management (also known a5 IPM). IPM emphasizes the •evaluation of all factors including environmental effects before chemicals are applied. Pesticides should only be used as a last resort. IPM maximizes the use of natural pest controls. Some of the tactics that can be used to decrease or eliminate the use of pesticide sprays include: tr~n of Natural Predators. Pathocens: Because sprays generally kill many beneficial insects instead of just the target pest, it may be necessary to introduce natural predators back into the garden. Ladybugs, lacewings, predatory wasps, and nematodes are all commercially available. Gartersnakes and toads are also predators and should not be eliminated from the garden. ~. There are some bacteria, viruses, and insect parasites that are specific to pests and will not harm other insects or animals. A commonly used bacterium in the Puget Sound area is Baci/!us thuringiensis IBtI, which is intended to control infestations of tent caterpillars. Habitat Chances: Many times a change of habitat can control pest infestations. Removal of old tires can cut down on the mosquito population by removing a convenient water-filled location that they can breed in. Crop rotation, even in a small garden can reduce the number of pest infestations. Removing last year's leaves from under rose bushes can cut down on the incidence of mildew and blackspot, as these Tungi overwinter in tlead leaves. Timinc: Craps that can overwinter Isuch as leeks or carrots) should be planted in the fall. This gives them,the time to become established before pests appear in the spring. Mechanical: Many eggs, larvae, cocoons, and adult insects can be removed by hand. Be sure that the insect is properly identified prior to removing it so that Residential t p Best Management Practices Stormwater Program-Guidance Manual Vclume Il 4. Never apply pesticides near streams, ponds, or wetlands. Do not apply them to bare or eroded ground. Many pesticides bind to soil particles and can be easily carried into a stream or storm drain. 5. Pesticides should be stored well away from living areas. Ideally, the storage area should have a cement floor and be insulated from temperature extremes. Always keep pesticides in their original containers with labels intact. Labels often corrode and become illegible in this climate and may have, to be taped onto the container. 6. Federal law now requires that all pesticides be labelled with the appropriate disposal method. Leftovers should never be dumped anywhere, including a landfill. Many counties in this area conduct hazardous waste collection days or collect waste regularly at the landfill. Contact the county environmental health department for more information. 7. Empty containers should be triple-rinsed and the leftover rinse water used as spray. Once containers are triple-rinsed, they are not considered hazardous waste and may be disposed of in most landfills. However, call your local landfill before putting the container in the garbage. 8.' If a pesticide is spilled onto pavement, it can be absorbed using kitty litter or sawdust. The contaminated absorhent should be bagged and labeled and taken to a hazardous waste collection site. If the pesticide is spilled onto dirt, dig up the dirt, place it in a Dlastic bag and take it to a hazardous waste collection center. 9. Many pest control companies and licensed applicators have access td pesticides that are more toxic than those available to the consumer. Check with the company before they spray indoors or outdoors to find out what spray they will be using and what precautions, if any, are necessary after the operator leaves. HOME REMODELING Remodeling uses some of the most toxic substances found in the home. Paints, preservatives, strippers, brush cleaners, and solvents all contain a wide range of chemicals, some of which are suspected to be carcinogens (cancer-causing). These products should never be dumped in a landfill or put down a sewer or septic system. Residential 12 Bes[ Management Practices Stormwater Program Guidance Manual Volume 11 1. When building a deck consider using wood instead of concrete. Wood decking allows rainwater todrip onto the ground below, keeping it from becoming surface runoff. 2. Decks and sidewalks can also be built out of brick interlocking pavers or modular concrete. If these surfaces are placed on a bed of well-drained soil, gravel or sand, rainwater can infiltrate into the ground through them. 3. To reduce disposal problems, buy only the amount you need. Used turpentine or brush cleaner can 6e filtered and reused. Paint cans should be allowed to dry and then be disposed of during a hazardous waste collection day or at a permanent collection location. 4. Large amounts of .leftover paint canbe given away, for example to a theater group. Currently, the City of Seattle is experimenting with recycling latex paint turneff in as hazardous-waste. It is blended, cleaned, tinted, and is now being sold on a trial basis as "Seattle Beige." 5. Roof downspouts cambe adapted to infiltrate runoff where the soil is well drained. The runoff from them can enter a gravel bed where it can infiltrate into the ground. "For design criteria, see BMP RI-15, Roof Downspout Systems in Volume III ofthe Stormwater Management Manual for the Puget Sound Basin. 6. When gardening on slopes, reduce the potential for surface runoff by using terraces across the face of the hill. These can be as simple as little soil "bumps" or can be elaborate using such products as pressure-treated wood 4x4s or rock walls. SEPTIC SYSTEM CARE AND MANAGEMENT While septic systems do not seem to have a direct relationship with Stormwater runoff, they can in some instances be related. Roof drains and Stormwater runoff should be diverted away from drainfields. Excess water reduces the capacity of the drainfield to absorb effluent from the septic tank. Residential 13 Bes[ Management Pracfices Stormwater Program Guidance Manual Volume 1/ _ 2. Water from hot tubs should not be drained into a septic system all at once. They are not designed to handle large volumes of chlorinated water. Either use the water on plants in the yard, or drain the hot tub slowly over a period of days. Septic tank tanks should be pumped regularly. Ponded water, damp places in the yard, foul odors and/or a dark gray or hlack soil color may indicate septic drainfield failure. Effluent from a malfunctioning septic tank can cause disease and nitrate problems in groundwater. LARGE ANIMAL MANAGEMENT People often own livestock in low-density residential areas. Horses are the most popular animal, but goats, cows, sheep, llamas, pigs and chickens are also kept. Nearby streams and lakes can be adversely affected by manure-contaminated Stormwater draining from pastures. Overgrazing, a common problem, denudes pastures and allows excessive runoff and erosion. Contamination frequently occurs when animals defecate directly info a lake or stream. Streambanks can also be broken down. It is essential for livestock owners to install BMPS similar to those described below. Not only will they help in controlling water quality, but they willhelp maintain productive pastures by increasing the grass cover and reducing erosion. Pasture management Pastures should be fenced to keep animals away from surface water. If stock must be watered•at a stream, use cramp-and-fence system to keep them out of the water (Figure 1). A minimum t0-foot strip of vegetation should be left between the fence and the water. 2. If the buffer area around the water cannot be fenced., it should be planted with a "living fence," vegetation that is impenetrable to livestock. The buffer strip should 6e at least 25 feet wide. Consult with local government for any other restrictions and/or the restrictions contained in a Sensitive Areas Ordinance, if passed. 3. Avoid overgrazing. Restrict grazing during the winter months when grasses are dormant and easily overgrazed. Grazing when the soil is wet can cause compaction Residential ~q Besf Management Practices Stormwater Program Guidance Manua/ 1/nhimo // of the soil and can result in reduced plant growth, erosion; and contamination of surface water. 4. If animals must be kept in a pasture over the winter, a small "sacrifice" area should be used for feeding and watering. This will limit the amount of land disturbed and reduce the area of pasture that will need reseeding. The sacrifice area should be located away from streams or standing water. Portahle electric fencing can 6e used to keep the animals in this temporary area. 5. Always limit the number of animals pastured based on the amount of land available and pasture productivity. The local Conservation District can offer advice on the proper stocking rate for your land. The smaller the acreage grazed, the greater the chance for vegetative destruction, even when hay is provided. 6. Intensive livestock use may necessitate reseeding of a pasture every two to three years to optimize production and minimize the chance of erosion. Ideal renovation entails plowing the pasture and sowing an annual crop such as corn, oats, or annual rye grass for one year and reseeding again the following year. Animals should be kept off the new seeding for the first year. Fields may be hayed towards the end of the first growing year. 7. Ifplanting an alternate crop for one year is not possible, some coverage and plant species improvement can be achieved by disking the pasture and reseeding. 6. Overgrazing can also be avoided by dividing the pasture into three or more units and establishing a grazing rotation period that allows foliage three to four weeks of regrowth between grazing periods. A portable electric fence can also be used in this situation. 9. The Soil Conservation Service and the County Conservation District can provide growers with details of these practices. Residential t 5 Best Managemenf Practices Storm water Program Guidance Manual Volume lI Figure 1 zxy"aR onr~ sroy DevrcE ~ P,cEV~r CA7TtE /rOOVbS PPphl SL/PPINrs IN1U 3'+XEAAl Hof ~ _ i ii ~ = ~ . "~ _~~ WIRE ~~/ RAMP // // /% ~ / Animal waste manacement 1. Manure should be collected regularly and stored. The storage site should be an area well away from creeks, ditches, marshes, and ponded or flowing water, where off- site runoff cannot mix with manure and where seepage from manure cannot enter surface water. 2. Stored manure should be covered with either a roof~or plastic sheeting to prevent the entry of rainwater.. Rooftop runoff from the manure storage area should be diverted away from the storage area by using gutters and downspouts. This clean water can be infiltrated back into the ground to recharge ground water. BMPs III-RI-t 5 and III- RI-16 in Volume III of the Stormwater Management Manual for the Puget Sound Basin give design criteria for roof downspout infiltration systems. 3. Small watercourses adjacent to the manure storage area should be redirected or enclosed. To do any work in or on streambanks, a short-term water quality modification permit or a hydraulic permit approval may be required. 1 Residential I 76 Best Management Practices i I Stormwater Program Guidance Manual I Volume lI 4. Concrete slabs with walls or curbs will provide the most control for manure storage. The storage area should 6e designed so that liquid wastes are retained and directed to a liquid storage area. 5. Manwe may be given away, or used as fertilizer on seeded pastures. i I REFERENCES Puget Sound Water Quality Authority, Manacinc Nonooint Pollution - an Action Plan for Puaet Sound Watersheds, 88-81, June, 1989. Washington State Dept. of.Ecology, Water Quality Guide -Recommended Pollution Control Practices for Homeowners and Small Farm Operators 87-30, revised June, 199E - Washington State Dept. of Ecology, Hazardous Waste Pesticides, 89-41, August, 1989. Washington State Dept. of Ecology, Turnino the Tide on Toxics in the Home 1989. Residential 17 Besi Management Practices BMPS for Description of Pollutant Sources: Landscaping can include grading, soil Landscaping transfer, vegetation removal, pesticide and fertilizer applications, and and Lawn/ watering. Stormwater contaminants include toxic organic compounds, Vegetation heavy metals, oils, total suspended solids, coliform bacteria, fertilizers, and Management pesticides. Lawn and vegetation management can include control of objectionable weeds, insects, mold, bacteria and other pests with chemical pesticides and is conducted commercially at commercial, industrial, and residential sites. Examples include weed control on golf course lawns, access roads, and utility corridors and during landscaping; sap stain and insect control on lumber and logs; rooftop moss removal; killing nuisance rodents; fungicide application to patio decks, and residential lawn/plant core. Toxic pesticides such as pentaehlorophenol, carbamates, and organometallics can be released [o the environment by leaching and dripping from treated parts, container leaks, product misuse, and outside storage of pesticide contaminated materials and equipment. Poor management of the vegetation and poor application of pesticides or, fertilizers can cause appreciable s[ormwa[er contamination. Pollutant Control Approach: Control of fertilizer and pesticide applications, soil erosion, and site debris to prevent contamination of stormwa[er. Develop and implement an Integrated Pest Management Plan QPM) and use pesticides only as a last resort. If pesticides herbicides are used they must be carefully applied in accordance with label instructions on U.S. Environmental Protection Agency (EPA) registered materials. Maintain appropriate vegetation, with proper fertilizer application where practicable, to control erosion and the discharge of s[ortnwa[er pollutants. Where practicable grow plant species appropriate for the site, or adjust the soil properties of [he subject site [o grow desired plan[ species. Applicable Operational BMPS for Landscaping • Install engineered soil/landscape systems to improve [he infiltration and regulation of s[ormwater in landscaped areas. • Do not dispose of collected vegetation into waterways or storm drainage systems. Recommended Additional Operational BMPS for Landscaping: • Conduct mulch-mowing whenever practicable • Dispose of grass clippings, leaves, sticks, or other collected vegetation, by composting, if feasible. August 2001 Volume IV -Source Control BMPS 2-23 • Use mulch or other erosion control measures when soils are exposed for more than one week during [he dry season or two days during [he rainy season. • If oil or other chemicals are handled, store and maintain appropriate oil and chemical spill cleanup materials in readily accessible locations. Ensure [hat employees are familiar with proper spill cleanup procedures. • Till fertilizers into the soil rather than dumping or broadcasting onto the surface. Determine the proper fertilizer application for the types of soil and vegetation encountered. • Till a topsoil mix or composted organic material into [he soil [o create a well-mixed transition layer that encourages deeper root systems and drought-resis[an[plants. • Use manual and/or mechanical methods of vegetation removal rather than applying herbicides, where practical. Applicable Operational BMPs for the Use of Pesticides: • Develop and implement an IPM (See section on IPM at end of BMP) and use pesticides only as a last resort. • Implement a pesticide-use plan and include a[ a minimum: a list of selected pesticides and [heir specific uses; brands, formulations, application methods and quantities to be used; equipment use and maintenance procedures; safety, storage, and disposal methods; and monitoring, record keeping, and public notice procedures. All procedures shall conform to the requirements of Chapter 17.21 RC W and Chapter 16-228 WAC (Appendix IV-D R.7). • Choose the leas[ toxic pesticide available that is capable of reducing the infestation to acceptable levels. The pesticide should readily degrade in the environment and/or have properties that strongly bind it to the soil. Any pest control used should be conducted at the life stage when the pest is most vulnerable. For example, if it is necessary to use a Bacillus thurin iex ns is application [o control [en[ caterpillars, i[ must be applied before the caterpillars cocoon or it will be ineffective. Any method used should be site-specific and not used wholesale over a wide area. • Apply the pesticide according to label directions. Under no conditions shall pesticides be applied in quantities that exceed manufacturer's instructions. • Mix the pesticides and clean the application equipment in an area where accidental spills will no[ enter surface or ground waters, and will not contaminate the soil. 2-24 Volume IV -Source Control BMPs August 2001 • Store pesticides in enclosed areas or in covered impervious containment. Ensure that pesticide contaminated stormwater or spills/leaks of pesticides arc not discharged to storm drains. Do not hose down the paved areas to a storm drain or conveyance ditch. Store and maintain appropriate spill cleanup materials in a location known to all near the storage area. • Clean up any spilled pesticides and ensure [hat the pesticide contaminated waste materials are kept in designated covered and contained areas. • The pesticide application equipment must be capable of immediate shutoff in the even[ of an emergency. • Do not spray pesticides within 100 fee[ of open waters including wetlands, ponds, and streams, sloughs and any drainage ditch or channel that leads to open water except when approved by Ecology or the localjurisdic[ion. All sensitive areas including wells, creeks and wetlands must be flagged prior [o spraying. • As required by the local government or by Ecology, complete public posting of the area [o be sprayed prior to the application. • Spray applications should only be conducted during weather conditions as specified in [he label direction and applicable local and state regulations. Do not apply during rain or immediately before expected rain. Recommended Additional Operational BMPs for the use of pesticides: • Consider alternatives to the use of pesticides such as covering or harvesting weeds, substitute vegetative growth, and manual weed control/moss removal. • Consider the use of soil amendments, such as compost, that are known ' to control some common diseases in plants, such as Py[hium root rot, ashy stem blight, and parasitic nematodes. The following are three possible mechanisms for disease control by compost addition (USEPA Publication 530-F-9-044): 1. Successful competition for nutrients by antibiotic production; 2. Successful predation against pathogens by beneficial microorganism; and 3. Activation ofdisease-resistant genes in plants by composts. Installing an amended soilAandscape system can preserve both [he plant system and the soil system more effectively. This type of approach provides a soiUlandscape system with adequate depth, permeability, and organic molter to sustain itself and continue working as an effective stornnvater infiltration system and a sustainable nutrient cycle. August 2001 Volume IV -Source Control BMPs 2-25 • Once a pesticide is applied, its effectiveness should be evaluated for passible improvement. Records should be kept showing the applicability and inapplicability of [he pesticides considered. • An annual evaluation procedure should be developed including a review of the effectiveness of pesticide applications, impact on buffers and sensitive areas (including potable wells), public concerns, and recent toxicological information on pesticides used/proposed for use. )f individual or public potable wells are located in the proximity of commercial pesticide applications contact the regional Ecology hydrogeologist to determine if additional pesticide application control measures are necessary. • Rinseate from equipment cleaning and/or triple-rinsing of pesticide containers should be used as product or recycled into product. • The application equipment used should be capable of immediate shutoff in the event of an emergency. For more information, contact the WSUExtension Home Assist Program, (253) 4#5-4556, or Bio-Integral Resource Center (BIRC), P.O. Dox 7414, Berkeley, CA.94707, or the Washington Department of Ecology to obtain "Hazardous Waste Pesticides" (Publication #89-41); and/or EPA to abtnin a publication entitled 'Suspexded, Canceled and Restricted Pesticides" which lists all restricted pesticides and the speck uses that are n/Iowed. Ya/uable informationv from these sources may also be available on the Internet. Applicable Operational BMPs for Vegetation Management: • Use at least an eight-inch "topsoil" layer with a[ least 8 percent organic matter [o provide a sufficient vegetation-growing medium. Amending existing landscapes and turf systems by increasing [he percent organic matter and depth of topsoil can substantially improve the permeability of the soil, the disease and drought resistance of [he vegetation, and reduce fertilizer demand. This reduces the demand for fertilizers, herbicides, and pesticides. Organic matter is [he least water-soluble form of nutrients [hat can be added to the soil. Composted organic matter generally releases only between 2 and 10 percent of its total nitrogen annually, and this release corresponds closely to [he plant growth cycle. If natural plan[ debris and mulch are re[umed to the sail, this system can continue recycling nutrients indefinitely. • Select the appropriate turfgrass mixture for your climate and soil type. Certain tall fescues and tye grasses resist insect attack because the symbiotic endophytic fungi found naturally in their tissues repel or kill common Icaf and stem-eating lawn insects. They do no[, however, repel root-feeding lawn pests such as Crane Fly larvae, and are toxic to ruminants such as cattle and sheep. The fungus causes no known 2-26 Volume IV -Source Control BMPs Augusf 2001 adverse effects to the host plant or to humans. Endophytic grasses are commercially available and can be used in areas such as parks or golf courses where grazing does not occur. The local Cooperative Extension office can offer advice on which types of grass are best suited to the area and soil type. • Use the following seeding and planting BMPs, or equivalent BMPs [o obtnin information on grass mixtures, temporary and permanent seeding procedures, maintenance of a recently planted area, and fertilizer application rates: Temporary Seeding, Mulching and Malting, Clear Plastic Covering, Permanent Seeding and Planting, and Sodding as described in Volume II). Selection of desired plant species can be made by adjusting the soil properties of [he subject site. For example, a constructed wetland can be designed to resist the invasion of reed canary grass by layering specific strata of organic matters (e.g, compost forest product residuals) and creating a mildly acidic pH and carbon-rich soil medium. Consult a sail restoration specialist for site-specific , conditions. Aerate lawns regularly in areas of heavy use where [he soil [ends [o become compacted. Aeration should be conducted while [he grasses in the lawn are growing most vigorously. Remove layers of thatch greater than'/a-inch deep. Mowing is astress-creating activity for [urfgrass. When grass is mowed too short its productivity is decreased and there is less growth of roots and rhizomes. The turf becomes Tess tolerant of environmental stresses, more disease prone and more reliant on outside means such as pesticides, fertilizers and irrigation to remain healthy. Se[ [he mowing height at [he highest acceptable level and mow at times and intervals designed [o minimize stress on [he turf. Generally mowing only 1/3 of the grass blade height will prevent stressing the turf. 7rrisation: The depth from which a plant normally extracts water depends on the rooting depth of [he plan[. Appropriately irrigated lawn grasses normally root in the [op 6 [0 12 inches of soil; lawns irrigated on a daily basis often root only in [he top I inch of soil. Improper irrigation can encourage pest problems, leach nutrients, and make a lawn completely dependent on artificial watering. The amount of water applied depends on the normal rooting depth of the [urfgrass species used, the available water holding capacity of the soil, and the efficiency of the irrigation system. Consult with the local water utility, Conservation District, or Cooperative Extension office to help determine optimum irrigation practices. August 2001 Volume IV -Source Control BMPs 2-27 Fertilizer Management: • Turfgrass is most responsive to nitrogen fertilization, followed by potassium and phosphorus. Fertilization needs vary by site depending on plant, soil and climatic conditions. Evaluation of sail nutrient levels throu_h regular testing ensures the best possible efficiency and economy of fertilization. For details on soils testing, contact [he local Conservation District or Cooperative Extension Service. • Fertilizers should be applied in amounts appropriate for the target vegetation and a[ the time of year that minimizes losses [o surface and ground waters. Do no[ fertilize during a drought or when the soil is dry. Alternatively, do not apply fertilizers within three days prior to predicted rainfall. The longer the period between fertilizer application and either rainfall or irrigation, [he less fertilizer runoff occurs. • Use slow release fertilizers such as methylene urea, IDBU, or resin coated fertilizers when appropriate, generally in [he spring. Use of slow release fertilizers is especially important in areas with sandy or gravelly soils. • Time the fertilizer application to periods of maximum plant uptake. Generally fall and spring applications are recommended, although WSU turf specialists recommend four fertilizer applications per year. • Properly trained persons should apply all fertilizers. A[ commercial and industrial facilities fertilizers should not be applied to grass swales, filter strips, or buffer areas that drain [o sensitive water bodies unless approved by [he localjurisdiction. /ntegrated Pest Management An IPM program might consist of the following steps: Step l: Correctly identify problem pests and understand their life cycle Step 2: Establish tolerance thresholds for pests. Step 3: Monitor to detect and prevent pest problems. Siep 4: Modify the maintenance program [o promote healthy plants and discourage pests. Step 5: Use cultural, physical, mechanical, or biological controls first if pests exceed [he tolerance thresholds. Step 6: Evaluate and record the effectiveness of [he control and modify maintenance practices to support lawn or landscape recovery and prevent recurrence. For an elaboration of these steps refer to Appendix IV-F. 2_pg Volume IV -Source Control BMPs August 2007 BMPs for Description of Pollutant Sources: Common road debris including eroded Maintenance of soil, oils, vegetative particles, and heavy metals can be sources of Roadside Ditches stormwater pollutants. Pollutant Control Approach: Roadside ditches should be maintained to preserve the condition and capacity for which they were originally constructed, and to minimize bare or thinly vegetated ground surfaces. Maintenance practices should provide for erosion and sediment control (Refer to BMP landscaping and Lawn/Vegetation Management). Applicable Operational BMPs: Inspect roadside ditches regularly, as needed, to identify sediment accumulations and localized erosion. Clean ditches on a regular basis, as needed. Ditches should be kept fret of rubbish and debris. Vegetation in ditches often prevents erosion and cleanses runoff waters. Remove vegetation only when flow is blocked or excess sediments have accumulated. Conduct ditch maintenance (seeding fertilizer application, harvesting) in late spring and/or early fall, where possible. This allows vegetative cover to be re-established by the next wet season thereby minimizing erosion of [he ditch as well as making the ditch effective as a biofilter. In the area between the edge of the pavement and the bottom of [he ditch, commonly known as the "bare earth zone," use grass vegetation, wherever possible. Vegetation should be established from the edgc of the pavement if possible, or at least from the rop of the slope of [he ditch. Diversion ditches on top of cu[ slopes that are constructed to prevent slope erosion by intercepting surface drainage must be maintained to retain [heir diversion shape and capability. Ditch cleanings are no[ [o be left on [he roadway surfaces. Sweep dirt and debris remaining on [he pavement at the completion of ditch cleaning operations. Roadside ditch cleanings, not contaminated by spills or other releases and not associated with a stormwater treatment system such as a bioswale, may be screened [o remove litter and separated into soil and vegetative matter (leaves, grass, needles, branches, etc.). The soil fraction may be handled as `clean soils' and the vegetative matter can be composted or disposed of in a municipal waste landfill. For more information, please see "Recommendations for Management of Street Wastes," in Appendix IV-G of this volume. Roadside ditch cleanings contaminated by spills or other releases known or suspected to contain dangerous waste must be handled following the Dangerous Waste Regulations (Chapter 173-303 WAC) unless testing determines i[ is not dangerous waste. 2.38 Volume IV -Source Control BMPs August 2007 Examine culverts on a regular basis for scour or sedimentation a[ [he inlet and outlet, and repair as necessary. Give priority [o [hose culverts conveying perennial and/orsalmon-bearing streams and culverts near streams in areas of high sediment load, such as those near subdivisions during construction. Recommended Treatment BMPs: Install biofdtration swales and filter strips-See Chapter 9, Volume V) to treat roadside runoff wherever practicable and use engineered topsoils wherever necessary [o maintain adequate vegetation (CH2M Hill, 2000). These systems can improve infiltration and stormwater pollutant control upstream of roadside ditches. August 2001 Volume IV -Source Control BMPs BMPs for Description of Pollutant Sources: Facilities include roadside catch Maintenance of basins on arterials and within residential areas, conveyance systems, Storm Water detention facilities such as ponds and vnul[s, oil and water separators, Drainage and biofilters, scttling basins, inFltration systems, and all other types of Treatment stormwatec treatment systems presented in Volume V. Roadside catch Systems basins can remove from 5 [o I S percent of [he pollutants present in stormwatec. When catch basins are about 60 percent full of sediment, they cease removing sediments. Oil and grease, hydrocarbons, debris, heavy metals, sediments and contaminated water are found in catch basins, oil and water separators, settling basins, etc. Pollutant Control Approach: Provide maintenance and cleaning of debris, sediments, and oil from stormwatec collection, conveyance, and treatment systems to obtain proper operation. Applicable Operational BMPs: Maintain stormwatec treatment facilities according to the O & M ~ procedures presented in Section 4.6 of Volume V in addition to Ihe following BMPs: • Inspect and clean treatment BMPs, eonveynnce systems, and catch basins as needed, and determine whether improvements in O & M are needed. • Promptly repair any deterioration threatening the structural integrity of the facilities. These include replacement ofclean-out gates, catch basin lids, and rock in emergency spillways. • Ensure [hat storm sewer capacities are no[ exceeded and that heavy sediment discharges to [he sewer system are prevented. • Regularly remove debris and sludge from BMPs used for peak-rate control, treatment, etc. and discharge to a sanitary sewer if approved by the sewer authority, or truck to a local or state government approved disposal site. • Clean catch basins when the depth of deposits reaches 60 percent of the sump depth as measured from the bottom of basin to the invert of the lowest pipe into or out of the basin. However, in no case should there be less than six inches clearance from the debris surface [o the invert of the lowest pipe. Some catch basins (for example, WSDOT Type IL basins) may have as little as 12 inches sediment storage below the invert. These catch basins will need more frequent inspection and cleaning to prevent scouring. Where these catch basins are part of a stormwatec collection and treatment system, the system owner/operator may choose to concentrate maintenance efforts on downstream control devices as part of a systems approach. 2-40 Volume IV -Source Con(ra18MPS August 2001 • Clean woody debris in a catch basin as frequently as needed ro ensure proper operation of the catchbasin. • Post warning signs; "Dump No Waste -Drains to Ground Water," "Streams," "Lakes," or emboss on or adjacent to all storm drain inlets where practical. • Disposal of sediments and liquids from [he catch basins must comply with "Recommendations for Management of Street Wastes' described in Appendix IV-G of [his volume. Additional Applicable BMPs: Select additional applicable BMPs from this chapter depending on the pollutant sources and activities conducted at [he facility. Those BMPs include: • BMPs for Soil Erosion and Sediment Control at Industrial Sites • BMPs for Storage of Liquid, Food Waste, or Dangerous Waste Containers • BMPs for Spills of Oil and Hazardous Substances • BMPs for Illicit Connections to Storm Drains BMPs for Urban Streets. August 2001 Volume IV -Source Control BMPs 2-41