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i <br />TURN LANE DESIGN CHECKLIST(PAGEI OF2) <br />STEP 1 - DATA GATHERING <br />Location-� <br />State Roadway: 1 Intersection: - r <br />k <br />Left Turn Lane Design for Approach: N / S / E / W <br />❑ Right Turn Lane Design for Approach: N / S / E / W <br />Vehicle Speed Choose one. Shown in order of preference. <br />Page 3-2 Design Speed: !�O— mph z �r*.c <a ,� �" {- 'P <br />❑ 85th Percentile Speed: mph <br />❑ Statewide Average Speed: mph (page B-2, Figure B-1) <br />Forecast Traffic Choose one. Shown in order of preference. <br />Volumes Year Volumes (provided by District/Central <br />��,Design <br />Page 3-3 <br />ce Planning Staff) <br />❑ Historic Volumes (existing volumes extrapolated to L <br />estimate 20 year forecast volumes) <br />I <br />{ ❑ 20-Year Multiplier (documented by State Aid and found <br />the following County Reference Data: <br />at website under <br />'f —'�► <br />' http','/wNw.dot.state,mn.us/'stateaid/sa_ sah.htmI <br />I Turning Volumes: see graphic at right, also note the <br />fk number of lanes for each movement. <br />1 Daily Volumes <br />Major Street Daily Traffic Volumes: y a'' vehicles per day <br />I <br />� Minor Street Daily Traffic Volumes: _vehicles per day <br />Heavy <br />Commercial <br />Page 8-5 <br />Grade <br />Page 3-5 <br />Seasonal <br />Variations <br />Page 3-4 <br />Roadway <br />Geometry and <br />Corridor <br />Characteristics <br />Page 3-6 <br />Percent Heavy Vehicle: % (If percentage of heavy commercial is high special consideration should <br />be taken in Step 4 for deceleration and storage length of turn lane) <br />❑ Upgrade ❑ Downgrade <br />Grade of approach: —4—% (If greater than 3%, apply deceleration adjustment in Step 4) <br />Is there a large seasonal variation within the corridor (recreational routes, primary farm to market routes, etc)? If <br />yes, consider the variation and potential increase in traffic volumes during peak periods. Is it enough of an <br />increase to change the design? ❑ Yes, adjust traffic volumes XNo <br />Is the intersection located on a horizontal curve? If yes, adjust taper in Step 4. (See Page B-17 and Table B-8) <br />❑ Yes, on horizontal curve X No <br />Are there adjacent intersections that may influence the turn lane design? If yes, consider adjustments to the turn <br />lane design to better accommodate the constrained conditions. (See Pages B-23 and 24) <br />XYes, constrained location ❑ No <br />� <br />STEP 2 — DETERMINE FACILITY TYPE <br />Determine Rural vs. Urban (based on Access Management CategoryAssignments: ��TT <br />Facility Type -- <br />Page 3-3 Urban ❑ Rural <br />Expressway vs. Conventional (determined by Mn/DOT Office of Traffic, Safety and Technology) <br />❑ Expressway, Conventional <br />Intersection <br />Control ❑ Signalized: <br />Page 3-9 <br />sec cycle length �A Unsignalized ❑ Future Signal? (see Figure B-3) <br />Development of Turn Lane Design Guidelines <br />