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HomeMy WebLinkAbout2007-05-07; Traffic Safety Commission; ; At the intersection of Impala Drive and Orion Street, install a stop sign on each street( CITY OF CARLSBAD TRAFFIC SAFETY COMMISSION STAFF REPORT COMMISSION MEETING OF: May 7, 2007 LOCATION: INITIATED BY: Impala Drive at Orion Street Jack Mis sett 2460 Impala Drive Carlsbad, CA 92010 ITEMNO.6A REQUESTED ACTION: At their intersection of Impala Drive and Orion Street, install a stop sign on each street. BACKGROUND: At the April 2, 2007 Traffic Safety Commission meeting, the motion to install a stop sign only on Orion Street failed by a 2-2 vote. Due to a lack of majority vote, this matter was continued to the May 7, 2007 meeting of the Traffic Safety Commission. DATA: Orion Street intersects Impala Drive to create a 90° tum and with the location. of the entrance driveway to the City of Carlsbad maintenance yard, a T-intersection configuration exists. This intersection is located at the east end of the Palomar Woods Business Park and the northwest end of the City of Carlsbad Safety Center/Fleet Maintenance Complex. Orion Street is considered the stem of the T-intersection with Impala Drive/the Carlsbad Fleet Maintenance driveway representing the top of the T-intersection (see Exhibit 1). A Yield sign has previously been installed on the Carlsbad Fleet Maintenance exit driveway at the request of the Police Department to assign the right-of-way at this intersection for vehicles leaving the maintenance yard. Orion Street is a private street on public property that is not classified on the Circulation Element of the General Plan. It serves the Carlsbad Safety Center/Fleet Maintenance complex and also functions as a through street connection between Faraday A venue and Impala Drive. Orion Street has a curb-to-curb width of 40 feet and a daily two-way traffic volume of 530 vehicles immediately south of Impala Drive. Impala Drive is an industrial street with a curb-to-curb width of 52 feet that also is not classified on the Circulation Element of the General Plan. It serves a number of industrial lots and has a two-way daily traffic volume of 483 vehicles west of Orion Street. The Carlsbad Fleet Maintenance driveway is on the easterly leg of this intersection and is controlled by a Yield sign. Faraday A venue is being extended and is tentatively scheduled to open east of Orion Street in July 2007. At that time, it will provide a new east/west through street connection to Melrose Drive in the City of Vista. This new east/west connection will provide a direct link for Carlsbad's central industrial park area easterly to Melrose Drive and, as an alternate route, will help relieve congestion along Palomar Airport Road and at the El Camino Real/Palomar Airport Road intersection. It is anticipated that some westbound drivers on Faraday A venue may tum on Orion Street to reach Impala Drive and then Cougar Drive for access to northbound El Camino Real to by-pass the Faraday A venue/El Camino Real intersection. ( CITY OF CARLSBAD TRAFFIC SAFETY COMMISSION STAFF REPORT COMMISSION MEETING OF: May 7, 2007 (continued) ITEMNO. 6A For each stop sign request received by staff, appropriate traffic studies are undertaken. Unless installed for the purpose of assigning right-of-way, stop signs can cause substantial inconvenience to drivers and should be used only where warranted. One of the conditions at an intersection that may warrant consideration of installing a stop sign on the minor street is when the safe approach speed to the intersection for a driver on the minor street is less than 10 miles per hour due to visibility limitations. The 10 mile per hour safe approach speed to the intersection of vehicles on the minor leg is evaluated when there is a request to install a stop sign only on the minor street at the subject intersection. Except for unusual situations, the minor street at a T-intersection is generally considered to be the stem of the "T" with the major street being the top of the "T". For purposes of this report, two scenarios were investigated. First, Orion Street was analyzed as the minor street (and stem of the T-intersection) and Impala Drive/Carlsbad Fleet Maintenance driveway was considered the top of the T-intersection. Secondly, Impala Drive was analyzed as the minor street (and stem of the T-intersection) and Orion Street was considered the top of the T-intersection. Although a Yield sign has been installed on the Carlsbad Fleet Maintenance exit driveway at this intersection, the other two legs of the intersection are uncontrolled (Orion Street and Impala Drive). An uncontrolled intersection is one that does not have right-of-way assigned by the presence of a yield, stop sign, or a traffic signal. Drivers approaching an uncontrolled intersection consisting of either three legs or four legs have right-of-way assignment based upon the rules of the road. Additionally, the driver should have an unobstructed view of the entire intersection and sufficient length along the intersecting street for the vehicle operator to anticipate and avoid conflicts with approaching vehicles about to enter the intersection. When a driver on the minor street is traveling towards the intersecting major street, they reach a decision point where it is necessary to determine if braking to a stop is required because of a vehicle approaching the intersection on the major street that may constitute a conflict. The location of the decision point on the minor street must allow the driver sufficient distance to view to both the driver's right and left all approaching vehicles on the major street. The driver on the minor street, generally not having the right-of-way, can then initiate actions to slow, stop, or avoid a conflict with other vehicles, as necessary, when the minimum clear sight triangle distances are provided (see Exhibit 2). ( ( \ CITY OF CARLSBAD TRAFFIC SAFETY COMMISSION STAFF REPORT COMMISSION MEETING OF: May 7, 2007 (continued) ITEMNO. 6A For the analysis of local streets and, in this case, an industrial street, the minor street decision point is assumed to be 50 feet from the intersection conflict point when the vehicle on the minor street has an approach speed of 10 miles per hour. The design speed for an industrial street is 30 miles per hour as specified in the Carlsbad Engineering Department Design Standards. A distance of 200 feet (stopping sight distance for 30 miles per hour in accordance with the Sixth Edition of the Caltrans Highway Design Manual) along the major street must be provided to minor street drivers to view vehicles approaching the intersection. If the vehicle on the major street cannot be seen at the point of its minimum stopping sight distance from the intersection conflict point when the driver on the minor street is at the decision point location on the minor street, a stop sign can be considered for installation on the minor street so as to positively assign the right-of-way. A field investigation found that a driver on Impala Drive has sight visibility limited to approximately 102 feet when looking to the south for approaching vehicles on Orion Street. Similarly, a northbound driver on Orion Street has sight visibility limited to approximately 73 feet when looking to the west for a vehicle on Impala Drive. Line of sight limitations on the southwest corner of the intersection are due to landscaping growing at that location. A driver stopped or slowing on the minor street needs sufficient corner sight distance to safely perform a crossing maneuver or to turn left or right even when viewing the approaching vehicle. Consequently, with the 10-mile per hour safe approach speed criteria for drivers on both Impala Drive and Orion Street not being met to view approaching vehicles, a stop sign can be considered for installation on each street. RECOMMENDATION: The Traffic Safety Coordinating Committee recommends that at the intersection of Impala Drive and Orion Street a stop sign be installed on each street. It is further recommended by the Committee to replace the existing Yield sign at the Carlsbad Fleet Maintenance exit driveway with a stop sign. NECESSARY CITY COUNCIL ACTION: The City Council must adopt an ordinance to establish the stop signs on Impala Drive and on Orion Street, as recommended. --------L.~----------..------------LO CAT 10 N MAP EXISTING ''yl[LD" SIGN DR. LEGEND: © PROPOSED STOP SIGN LOCATION ~ EXISTING YIELD SIGN LOCATION @ TRAFFIC SIGNAL P-ROJECT NAME PROPOSED STOP SIGNS IMPALA DRIVE AND ORION STREET DRAl'tN BY: SCOTT EVANS, CARLSBAD ENG/NEERNG DEPT. J/14/07 C: lRAmc STOP S/GNS\STOP S/GN-/1,/PLALA-ORIONI.DWG NOT TO SCALE CARLSBAD SAFETY CENTER EXHIBIT 1 TITLE IMPALA DRIVE MINOR STREET I ◄ ( 50' -----7 DECISION POINT I I I NOT TO SCALE IMPALA DRIVE NOT TO SCALE REQUIRED LIN£ OF SIGHT ....... I ~ I ::i:.. I o "-:> I ~ 2 I r-- 1 8 I ~ ~ 200· REQUIRED I I ◄ 73' ACTUAL : ----------7 REQUIRED/ LIN£ OF SIGHT . I I I I VJ I a I I I 1- lli ~ Cf) ~ 0 -a::: 0 FLEET MAINTENANCE DRIVEWAY * FLEET MAINTENANCE DRIVEWAY DECISION POINT IMPALA DRIVE AND ORION STREET INTERSECTION APPROACH SIGHT TRIANGLE EXHIBIT 2 DRAltN BY: SCOTT EVANS, CARLSBAD ENGINEERING DEPT. J 14 07 C: 1RAmc STOP SIGNS STOP SIGN-IMPALA-ORION2.DWG