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TIA August 2003Yelm Subdivision Yelm, WA Transportation Impact Study August 18, 2003 Prepared for: DND Associates, LLC PO Box 310 Gig Harbor, Washington 98335 Prepared by: Transportation Engineering Northwest, LLC Transportation Engineering/Operations • Impact Studies • Design Services • Transportation Planning • Forecasting Seattle Office: PO Box 65254 • Seattle, WA 98155 • Office/Fax (206) 361-7333 • Toll Free (888) 220-7333 Eastside Office: 16625 Redmond Way, Suite M, PMB #323 • Redmond, WA 98052 • Office (425) 485-4663 • Fax (425) 398-5779 Yelm Subdivision Yelm, WA Transportation Impact Study 8 8th Ave v oc d E m 510 1 SR 510/Yelm AvelKillion Rd g1 `' y I 7 R~ ~ b~ Project Site 3 a_ _c .9 c 3 0 ~ Valiev Rd e 0 Y SR 510/Yetm Ave/Culleru St /`~, in i 05 b8 /°~ ~y 41 / A'c\ 1 -7 0 ~ ~ 2 ~ R~ o ~. ~ ~3 "~ ~b I Canal Rd CuRens SUCoates Rd R 9 O 11~ 7 ~ ? 1 ~ ?O .~ 0 ~ H ~ 2 -~ ? / ~ 5 ~ d B6 u ~ _: ~ 13 70 N ~ 7 .r r 1 I ~r+ U ?D ~ 34 86 "OatP~R q 1 115, 900 I 17, 507 507 SR 510/SR 507/t'st St / yP~~ 5~~10~ ~--~~~ ~Le ~' °'~~ yy x.51 ~4z ~ R titi 104th Ave q5 ~ e~'-~ u (Not to Scale) ~. 2~9 y ~9ti ,~ Transportation Figure 3 Yelm ~J Engineering 2003 Existing Daily and subdivision Northwest, i.i_c p,M. Peak Hour Traffic Volumes Tr,nsportttlon Impatt Study Au ust 18, 2003 Transportation En~eering NorehWat, ~~c g Page 6 Yelm Subdivision Yelm, WA __ Transportation Impact Study LOS F at signalized intersections is often considered unacceptable to most drivers, but does not automatically imply that the intersection is over capacity. Jammed conditions could occur on one or all approaches, with periods of long delays and drivers waiting for multiple signal cycles to progress through the intersection. For unsignalized intersections, a level of service and estimate of average control delay is determined for each minor or controlled movement based upon a sequential analysis of gaps in the major traffic streams and conflicting traffic movements. In addition, given that unsignalized intersections create different driver expectations and congestion levels than signalized intersections, their delay criteria are lower. Control delay at unsignalized intersections include deceleration delay, queue move-up time, stopped delay in waiting for an adequate gap in flows through the intersection, and final acceleration delay. The City of Yelm's level of service standard is LOS D. Table 1: Level of Service Criteria for Si naGzed and Unsi nalized Intersections Level of Service Signalized Intersection Dela Ran a (sec) Unsignalized Intersection Dela Ran a (sec) A <_ 10 5 10 B > 10 to __<20 > 10to<_ 15 C > 20 to<_35 > 15 to<_25 D > 35 to __<55 > 25 to<_35 E > 55 to<_80 > 35 to<_50 F > 80 > 50 source: "Highway Capacity Manual", Speaal Report 209, Transportation Research Board, 2000, Update. Existing p.m. peak hour levels of service at study intersections are summarized in Table 2. As shown, all intersections currently operate at LOS D or better under existing conditions. Movements on the southbound approach of SR 510/Yelm Avenue and Cullens Street are estimated to operate at LOS E, however, maximum queuing on this approach is less than 2 vehicles. Detailed level of service summary worksheets are provided in Appendix A. Table 2: Estimated 2003 P.M. Peak Intersection Levels of Service P.M. Peak Average Delay Signalized Intersections LOS (seconds) SR 510/Yelm Avenue at SR 507/152 Street D 36 P.M. Peak Average Delay Unsignalized Intersections LOS (seconds) Cullens Street at Coates Road A g WB (A) (9) Edwards Street/Crystal at Coates Road B 10 EB (A) (11) SR 510/Yelm Avenue at Killion Road D 32 SB (E) (35) SR 510/Yelm Avenue at Cullens Street D 32 SB (E) (41) LUa a-r -average LUJ for stop controlled and yield movements. Average Delay (seconds) -Average delay per vehicle of stop controlled and yield movements (in seconds). Delay of worst movement at unsignalized intersections are also reported. ~~ Transportation Engineering Northwest, LLC August 18, 2003 Page 7 Yelm Subdivision Yelm, WA Transportation Impact Study Public Transportation Services Intercity Transit provides public transportation services within Thurston County. Transit route 93 stops on Cullens Street in the vicinity of the Easthaven Villa Assisted Living Community and on Coates Road. Route 94 stops along SR 510. All stops are within reasonable walking distance to the project site at less than'/z mile. - Route 93 provides Saturday service within the City of Yelm "to major attractors such as the -- Nisqually Plaza and the Post Office. Service is provided from 8:30 a.m. until 7:25 p.m. with stops every hour. Route 94 provides weekday and Saturday service from Olympia to Yelm. Weekday service is provided between 6:15 a.m. and 6:55 a.m. with stops every hour. Saturday service is provided from 8:25 a.m. until 7:55 p.m. with stops every 2 hours. Nonmotorized Transportation Paved and/or gravel shoulders are provided on Cullens Street, SR 510, Edwards Street/Crystal Springs Road, and SR 507. Raised sidewalks are provided along parts of SR 510 and on Edwards Street/Crystal Springs Road, south of Coates Road. Planned Roadway Improvements The City of Yelm's Six-Year Transportation Improvement Plan (TIP), 2003-2008, identified the following transportation improvement projects that would be impacted by vehicular trips from the proposed residential complex: - Yelm Avenue (SR 510) at Killion Road Intersection. Widen roadway, re-align intersection and provide safety improvements. - Yelm Avenue (SR 510) from Solberg Street to First Street. Widen roadway to Urban Arterial standards. These standards would include two lanes with 10-foot travel lanes, a 7-foot parking lane on one side, and an 8-foot planting strip between curbs and 5-foot sidewalks on both sides. TRANSPORTATION IMPACT ANALYSIS The following section describes transportation impacts the proposed Yelm Subdivision would have on critical intersections in the site vicinity. The discussion includes non-project related traffic forecasts, new trips generated by the proposed development, distribution and assignment of new project trips, impacts on levels of service at nearby significant intersections, site access, circulation, and safety issues, and public transit and nonmotorized transportation impacts. Transportation En~eering Northwest, LLC August 18, 2003 Page 8 Yelm Subdivision Yelm, WA Transportation Impact Study Non-Projeet Traffie Forecasts For the purpose of this traffic analysis, year 2008 was selected as the build-out year based upon completion of the project as anticipated by the proponent. Based on historical traffic volumes in the site vicinity, the average annual traffic growth rate is estimated at approximately 2 percent. However, to estimate future traffic volumes, 2003 traffic volumes were factored by 4 percent per year to estimate 2008 baseline conditions'. Projeet Trip Generation Trip generation rates compiled by the Institute of Transportation Engineers (ITE) Trip Generation, 6`b Edition, 1997, were used to estimate daily traffic and the City of Yelm's Trip Generation Kate Default Values (Yeltn's Municipal Code, Table 15.40.030B) were used to estimate p.m. peak hour traffic that would be generated by the proposed action. Average trip rates (ITE land use code 210 and City of Yelm's Single Family Detached land use) were applied based upon total dwelling units (the maximum potential number of 205 dwelling units) to estimate new trips generated. Entering and exiting distribution percentages during the p.m. peak hour were obtained from the ITE Trip Generation. Table 1 summarizes estimated trip generation by the proposed action. An estimated total of 1,960 daily and 205 p.m. peak hour vehicular trips (130 entering and 75 exiting) would be generated at full build-out and occupancy of the project. Table 1: Projeet Trip Generation ITE P.M. Peak Trip Land Use Generation Daily Trip Land Use Code Units Enter Exit Total Generation Single Family Detached Housin 210 205 130 75 205 1,960 Source: IT'E Trip Generation Manual, 6~ Edition, 1997. Trip Distribution and Assignment Based upon traffic studies previously completed for residential projects within the immediate site vicinity, historical traffic volumes and patterns, and the regional employment distribution within the area, p.m. peak hour traffic volumes generated by the proposed action would be generally distributed as follows (also shown in Figure 4): - 45 percent westerly via SR 510/Yelm Avenue; - 35 percent southeasterly/easterly via SR 507; - 5 percent southerly via SR 507; and - 15 percent locally within the City of Yelm. Services Engineer, City of Yelm, e-mail to TENW on ust 12, 2003. August 18, 2003 Page 9 I Source: Jim Gibson Transportation Engineering Northwest, t.~c Yelm Subdivision Yelm, WA Transportation Impact Study Traffic Volume Impacts Figure 5 summarizes daily traffic impacts along the major corridors of SR 510 and SR 507. SR 510 west of SR 507/15L Street would experience the greatest increase in daily traffic volumes at 1,100 vehicles. Daily traffic volumes would also increase on SR 510 east of Longmire Street with 800 additional vehicles and on SR 507 east of SR 50/15[ Street with 700 additional vehicles. SR 510 and SR 507 are minor arterials, which are designed to carry these additional vehicular capacities. Future Levels of Service Intersection levels of service impacts were evaluated at study area intersections assuming full occupancy and operation in 2008 and are summarized in Table 3. As shown, the intersection of SR 510/Ye1m Avenue at Cullens Street would operate at LOS F without the project in 2008 and LOS F with the project. Given that the intersection would not meet City LOS standards in 2008, additional intersection improvements were identified to include separate left-turning lanes on SR 510 or a two-way center left-turning lane to better facilitate flow along SR 510 and provide queue storage for critical left turns onto/off of SR 510. Additionally, a separate southbound right-turn only lane is recommended. With these improvements, this intersection would operate at LOS C with or without the project in 2008. Left-turn movements represent critical turning movements at unsignalized intersections, increasing the potential for intersection delay and safety issues. As such, the potential need for an eastbound left-turn lane on SR 510 at its intersection with Cullens Street was conducted considering typical evening commute periods. Based upon procedures and guidelines found in Highway Research Kecord No. 211 -Volume Wlarrants for Left-Turn Storage Lanes at Unsignali~ed Grade Intersections and WSDOT's Design Manual, Left Turn Storage Guidelines, Tsvo-Lane, Unsignali~ed, May 2001, a separate eastbound left-turn (minimum 125-foot length) is warranted at this location under existing conditions and under future 2008 conditions with or without the project. Table 3: 2008' Intersection Level of Service Impacts Without Average Delay With Project Average Delay Pro~ect LOS (seconds) LOS (seconds) SR 510/Yelm Ave at SR 507/1` St. D 51 D 53 Without Average Delay With Project Average Delay Unsi nalized Intersections Pro"ect LOS (seconds) LOS (seconds) Cullens Street at Coates Road A 9 A 9 WB (A) (9) WB (B) (10) Edwards Street/Crystal Springs Rd at B 11 B 11 Coates Road EB (B) (12) EB (B) (13) SR 510/Yelm Avenue at Killion Rd E 47 E 37 SB (F) (59) SB (F) (63) SR 510/Yelm Avenue at Cullens St F 66 F > 100 SB (F) (< 100) SB (F) (> 100) With Intersection Improvements C 14 C 18 SB (D) (26) SB (D) (26) Lva A-r -average LUJ for stop controlled and yield movements. Average Delay (seconds) -Average delay per vehicle of stop controlled and yield movements (m seconds). 1 - Assumes a 22 percent growth in traffic over 2003 existing conditions, averaging 4 percent per yeaz. `~ August 18, 2003 Transportation Engineering Northwest, LLC Page 11 Yelm Subdivision Yelm, WA Transportation Impact Study 88th Ave -- PrOJeCt ------- - Canal Rd L a Site _.......__ m 3 v _ c .~ c 0 TS ~ N H ~ O C ~ 510 = Y u ~ c r =a O s P~ ~ c. ~ .QL P H ~ _= ~ ~ N ~t ~./ c~ ~~4;/ a ~° 00 Ber Valle Rd 20,800 800 (21,600) i _ ~` '~'` 19 700 S 1,100 ~ ~~ (20,800) 510 ~ Phj~P S St IPGP ~ ~~ GP ~S~ ,~ ~D Longmire St f d, ~ ~ P 9, i 00 fxr 100 (8,200) 507 507 ~ , .r.`" 21,000 700 yPi '~ (2L7oo) ~De ~ Legend ~ / 2- ~ xx - 2008 Baseline Traffic Volumes xx -Project Traffic Volumes 104th Ave a V (Not to Scale) Cxxl - 2008 W/th Project Tiafl7c Volumes j,~~jn Transportation Fi ure 5 g Yelm { Engineering Su bdivision ~ Northwest, LLC 2008 Daily T raffic Volu me Impacts Traruportadon Impact Study J August 18, 2003 Transportation Engineering Northwest, LAC Page 12 Yelm Subdivision Yelm, WA Transportation Impact Study The intersection at SR 510/Yelm Avenue and Killion Road would operate at LOS E with or without the project in 2008. All other intersections analyzed would operate at LOS D or better with and without the project. Detailed level of service summary worksheets are provided in Appendix A. Figure 6 shows peak hour project-generated traffic, and Figure 7 summarizes traffic volumes with and without the project during the p.m. peak hour. Site Aeeess, Safety, and Circulation Issues Vehicular site access would be provided via two separate driveways: 1) on Killion Road and 2) on Cullens Street. All driveway approaches would consist of single lane approaches. The internal roadway within the development would provide adequate on-site, two-way circulation and fire and emergency vehicle access with separate driveway entrances onto Killion Road and Cullens Street. Sight distance is the length of the roadway or straight-line distance a driver can see ahead at any particular time, and is taken as the minimum sight distance required for a driver to stop a vehicle after seeing an object in the vehicle's path without hitting that object. Sight distance is directly related to vehicle speeds and resultant distances traversed during perception and breaking reaction time. Entering sight distance is the minimum sight distance needed for the driver of a vehicle stopped at an intersection to safely cross a roadway or enter and achieve average running speed without interrupting approaching vehicles on the major street. The minimum stopping sight distance is 200 feet and entering sight distance is 310 feet fora 30 mph design speed based upon guidelines in the City of Olympia's Development Guidelines and Public lYlorks Standards, November 21, 2000, which is used by the City of Yelm. These sight distance requirements were originally set forth by the American Association of State .and Highway Transportation Officials (AASHTO's) A Policy on Geometric Design of Highway and Streets, 2001 (commonly referred to as the "Green Book"). Field estimates made by TENW in February 2003 indicate both project site driveways onto Killion Road and Cullens Street would exceed AASHTO's minimum sight distance requirements by 400 feet for both stopping sight distance (650 feet field estimate) and entering sight distance (750 feet field estimate). Public Transportation Impacts There are no significant public transportation impacts related to the proposed project. Existing bus stops served by Intercity Transit are within proximity (less than'/a mile) to the proposed site with stops on SR 510, Cullens Street and Coates Road. Nonmotorized Impacts As part of the project, full curbs, gutters and sidewalks would be provided on all property frontages of the project site. No additional impacts would occur to nearby nonmotorized facilities as a result of the proposed action. ~~ August 18, 2003 Transportation Engineering Northwest, LLC Page 13 Yelm Subdivision Yelm, WA Transportation Impact Study August 18, 2003 Transportation Engineering Northwest, L.I.C Page 15 Transportation Figure 7 Yelm ~~ Engineering 2008 P.M. Peak Hour Subdivision Northwest, Lt.c Traffic Volume Impacts Tramporradon Impatt Study ,s Yelm Subdivision Yelm, WA Transportation Impact Study PROJECT MITIGATION MEASURES The following system improvements are necessary to accommodate future traffic volumes in the site vicinity regardless of the proposed Yelm Subdivision. - Enhance the SR 510 at Cullens Street intersection by providing the following: separate left-turn only lanes on east/west legs of the intersections or installation of a two-way center left-turning lane on SR 510. Additionally, construct a southbound right-turn only lane on Cullens Street at this intersection, with a minimum storage of 100 feet. This improvement would be a candidate project for inclusion in the transportation facility charge ordinance, and is consistent with the planned SR 510 (Y-5) improvements identified as part of the City's Comprehensive Plan, 2001. To mitigate project traffic impacts, the project would be required to construct full curbs, gutters, and sidewalks along its property frontages on Cullens Street and Killion Road and widen the roadway cross-section to the City's minimum standards between the site access roadway and the improved road section. In addition, the City of Yelm administers a traffic mitigation impact fee rate on all proposed developments within the City to be applied to traffic-related improvements projects. The City of Yelm would determine and apply the charge on a per unit basis at the time of building permit issuance. Currently, this traffic impact fee is approximately $750 per single- family home. No other mitigation measures would be required as part of the proposed Yelm Subdivision `~ August 18, 2003 Tnnspomcion Eegineeriey Northwest, PLC Page 16