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KITTITAS COUNTY <br />DEPARTMENT OF PUBLIC WORKS <br />PUBLIC WORKS — BOARD OF COUNTY COMMISSIONERS <br />ENGINEER'S REPORT — NO 81 RD SPEED LIMIT REDUCTION REQUEST <br />PUBLIC HEARING DATE JUNE 6, 2017 <br />ACTION REQUESTED CONSIDER REDUCING THE POSTED <br />SPEED FROM 35 MPH TO 25 MPH <br />LEAD STAFF: Lucas Huck, County Engineer <br />RECOMMENDATION: <br />Reduce the current posted speed of 35 MPH to 25 MPH. <br />BACKGROUND: <br />The 2017 — 2022 Six Year Transportation Improvement Plan included a pedestrian <br />improvement project along No. 81 Road from Clerf Road to Alpine Estates. Recently Public <br />Works has found that the existing ditch and water conveyance along this portion of roadway <br />can support a four to five foot shoulder widening with minimal impact. This is a low cost high <br />benefit solution that will result in a sufficient width of pavement to accommodate a shared <br />use pedestrian and bicycle facility. <br />Currently the posted speed limit along No. 81 Road from Clerf Road to Palmero Park is 25 <br />MPH, at which it transitions to 35 MPH. The City of Kittitas has noticed the County of <br />increased pedestrian traffic along No. 81 Road from Alpine Estates to Palmero Park. The <br />notice resulted in our placement of the proposed improvement project on our current annual <br />2017 construction program. <br />DISCUSSION: <br />A variety of factors must be considered when determining safe and reasonable speed <br />limits. The prevailing speed is a major consideration in setting speed limits. <br />Engineers recommend setting speed limits so that 85% of the freely flowing traffic <br />travels at or below that speed (the 85th percentile). Guidance is provided in MUTCD <br />2B.13, recommending posted speed limits to be set "within 5 mph of the 85th <br />percentile speed of free-flowing traffic." Another consideration is the highest safe <br />speed for which the road was designed. This takes into account road type, road <br />geometry, and adjacent land use. Other factors include presence of non -vehicular <br />road users, driver or vehicle characteristics, enforcement capability, and public <br />attitudes. <br />The request to reduce the speed limit on No. 81 Road is driven by a concern for safety <br />of non -vehicular road users; although lowering the posted speed limit below the 85th <br />percentile may potentially make the road less safe for motorized travelers it has the <br />potential to reduce the risk of conflicts with non -vehicular road users. Traffic studies <br />Page 1 of 5 <br />PUBLIC WORKS BOARD OF COUNTY COMMISSIONERS ENGINEER'S REPORT <br />