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HomeMy WebLinkAboutA001 - Council Action Form dated March 28, 2000 Item # 5(0 Date: March 28, 2000 COUNCIL ACTION FORM SUBJECT: SPEED LIMITS IN CONSTRUCTION ZONES BACKGROUND: In past years, City staff has experienced difficulties lowering traffic speeds in construction zones where hazardous conditions exist for the motoring public, as well as for the construction workers. These hazardous conditions had frequently included narrowed traffic lanes, encroaching construction equipment, rough street surfaces, sharp turning roadway alignments, one-lane streets, and other hazardous work elements. Construction sites where these hazards had existed include Airport Road (South Riverside to South Duff), E.13t" Street (1-35 off-ramps to Dayton Avenue), South16th Street (Hwy 30 overpass to Dayton Avenue), 13t" Street (Hyland to Stange Road), and other construction sites along higher speed/volume arterial streets. Several methods had been tried to lower traffic speeds such as posting advisory speed limit and warning signs, and locating the changeable message signs within the construction zones. These methods, in many cases, did not result in lowered speeds. It had been reported by City inspectors that many motorists simply ignore the signage, and traveled faster than considered safe along these construction zones. When conditions became particularly hazardous, police were called to monitor traffic speeds. However, this effort was not entirely effective since officers could not write tickets based on the advisory construction speed limits, but only on the higher speed limits as specified in the City Code. Due to these conditions, staff has explored alternative measures to lower traffic speeds within construction sites. As part of this work, staff queried other cities concerning their practices, whereas most had relied exclusively upon advisory speed limit signage as did the City. However, two cities (i.e., Iowa City and Omaha) did establish temporary "authorized" speed limits in the construction zones so that law enforcement could be utilized to effectively monitor speeds and write tickets. These temporary speed limits were established by two different methods. One method practiced by Iowa City was to designate temporary "authorized" speed limits as part of their traffic control plans for projects. With these plans, speed limits are designated in the construction zones by City Council approval (of the plans and specifications) and remain until the project is completed. The other method practiced by the City of Omaha is to authorize the City Traffic Engineer to designate speed limits within construction on an "as needed" basis if advisory signage is ineffective in controlling speeds. It should be noted that the Iowa Department of Transportation also designates temporary speed limits in construction zones along highways and interstates, and these are established by the regional construction engineer. According to traffic studies, designating temporary "authorized" speed limit zones in construction sites is one of the most effective methods in reducing traffic speeds. Texas DOT studies showed that law enforcement could reduce speeds by an average of 18%, or 12-13 mph on urban arterial streets with a 35-mph speed limit. As indicated in the study, this measure was more effective than other methods, such as placing changeable message signs CAF — Speed limits in construction zones March 28, 2000, - Page 2 and reducing lane widths to slow traffic speed. In these cases, the traffic speeds were reduced by 3-4 mph within construction zones in both cases. According to Iowa DOT engineer Mark Bortle, the lowered speed limits within construction sites along the interstate and highways have also enhanced safety, especially when enforcement is actively monitoring speeds. Staff believes that the temporary speed limits should be designated to enhance safety in construction zones. Attached is a proposed "Street Work Zone Regulations" that provides the mechanism to designating temporary speed limits within signed construction zones. According to this regulation, the City traffic engineer would reasonably designate a temporary speed limit, under standards of good engineering practice that would be the maximum rate of speed consistent with the safety of pedestrian workers engaged in construction or maintenance work. This speed limit should be posted on signs that mark the start of the Street Work Zone, and be designated in the zone that extends to the signing that ends the Work Zone. This street zone regulation would allow staff to designate these temporary speed limits within construction zones in a very short and timely manner to protect workers and the public when hazardous are present. In most cases, the speeds would be lowered to not less than 25 mph along arterial streets to accommodate sharp turns, restricted street widths, and untypical traffic conditions. To be effective, conditions would have to be continually monitored where temporary speed limits are applied to ensure that they are reasonable. This includes ensuring that speed limits are not designated along areas where construction work is not occurring, and/or street geometrics and conditions are normal. Staff does believe that the reduced speeds will be designated only in a few cases each year on an "as needed" basis for the protection of the motoring public, construction workers, and city inspectors. To be clearly marked, the zone will have signage designating the starting and ending point for the speed limit. ALTERNATIVES: 1. Approve the "Street Work Zone Regulations" that establishes a mechanism for implementing temporary speed limits in construction zones. 2. Establish temporary speed limits by inclusion in construction plans and specifications, which are subsequently approved by City Council. 3. Do nothing. MANAGER'S RECOMMENDED ACTION: It is the recommendation of the City Manager that the City Council adopt alternative number 1, thereby approving the "Street Work Zone Regulations" that establishes a mechanism for implementing temporary speed limits in construction zones. COUNCIL ACTION: