2021.0009 16404 Infiltration16404 Middle Street Storm Infiltration Trench
Based on the provided soil logs and impervious area of 1,504 square feet, we propose to install an
infiltration trench with the following dimensions:
30 feet long
Two feet wide
18 inches deep
See attached cross section.
rod
PLAN VIEW drain
4" rigid ar !s flexbie
NTS perforated pipe
-------------------- —
..,...
---------------------------
-------------- q7surripw/solidlid
PLAN VIEW roof drain
NTS
overflow
C rigid or r flembie spm bkK*
perforated pipe
S
12" : a a washed rode __ 0� � ° o ' oc C14 1' 5.9 min
1 112"-w4 V Q V o a' 3' min
tine mesh scree �-- CB sump w/solid lid
3 A' min
SECTION A
NTS
4' rigid or V flexible
perforated pipe
washed rock
1 1/2"-W47
Figure 3.1.2 - Typical Downspout Infiltration Trench
Source: King County
Volume III — Hydrologic Analysis and Flow Control BM -Ps — December 2014
3-7
irom roof
9m�
overflow B" min
�b
1Ile -als'o°a aQve -
washed rod&... length
0 0 ej (3 Ur min f�TE Same 1 dunenseorzs
C3
,00 and site limitations as 4Ticatl system
L2' min 1$' Min
X -SECTION
[QTS
Figure 3.1.3 - Alternative Downspout Infiltration Trench System for Coarse Sand and Gravel
Sourcc: King County
Volume III — Hydrologic Analysis and Flow Control BMPs — December 2014
3-8
random fib
IN
filter t baric
eQ9 ,6Qp- _4-perfpipe .
16' Pain0. o O o VDO o Q 1Ile -:340 "stwd roi*
oQaq 4boq oq a bqq
O p
�4 n u° o e.Gn A¢fS y oa
H-- 2a' rri n
TRENCH X-SECTION
NTS
dope —.
to road
drainage system
zI x fly
level trench
WWP"
PLAN V19W.OF ROOF
NTS
Source: King County
Figure 3.1.8 - Perforated Stub -Out Connection
Volume III — Hydrologic Analysis and Flow Control BMPs — December 2014
3-18
W1�,Aj?72�
SFR INFILTRATION DISPERSION SYSTEM
SOIL LOG EVALUATION REPORT
(W1e ST 1 rte. Go7 ! Sheet
SOIL LOG NUMBER:
Number shalt match site -Ian -� _ ��=---- _-.-- —--'-
1. SITE ADDRESS:
2. PARCEL NUMBER: 1
3. SITE DESCRIPTfON:
(j Z�V�( C)fP.
/,,ITU2t' CRASS
4. LIST METHODS USED TO EXPOSE, SAMPLE AND TEST SOILS:
IY'o -_
5. NUMBER OF TEST HOLES 6. SATURATED INFILTRATION PAT_..
LOGGED:
U Inches i Hour
7. HAS FILL MATERIAL BEEN PLACED OVER 9, DEPTH TO SEASONAL HIGH WATER:
THE PROPOSED TRENCH AREA?
U'i o
8 N0 YES
10. CURRENT WATER 11. DEPTH TO IMPERVIOUS 12, PROFILE DESCRIPTION:
DEPTH: LAYER:--
Vo 7
MOTTLIT-413 I'vDUF AT10N
HORIZON See Note 1 DEPTH TEXTURAL CLASS
� _. _. _.. ._ _._ _ ..._ __
Note 1: Identify limits of any outwash type soils (i.e. those meeting USDA soil texture classes ranging from,
coarse sand and cobbles to medium sand.
I hereby state that I prepared this report, and conducted or supervised the performance of related ,vrirk. I state
that I am qualified to do this work. I represent my work to be complete and accurate within + ruff �;
uncertainty inherent to the actic8 f soil scien nd to be suitable for its intended ustx
SIGNED: 9
i
,'
LICENSED STAMP: w'�
DATE: «• l
'Sian &Date , t) .. ..P PA
9
n _... n e 11 C/ 1 G