(A) Alternative traffic management strategies should always be pursued before the decision is made to install speed humps. These strategies include:
(1) Reviewing, establishing, and/or revising and enforcing general laws and ordinances pertaining to speed limits and other traffic control management items.
(2) Educating residents and neighborhood groups so they can better understand causes of traffic problems, potential solutions to these problems, and the advantages and disadvantages of implementing different solutions.
(3) Installing specific regulatory, warning, and guide message signs or other traffic control devices.
(B) Speed humps are an effective and appropriate device for safely reducing vehicle speeds on certain types of streets when all of these other speed control alternatives have been investigated and determined to be ineffective. In order for speed hump installations to be effective, they should be located selectively in accordance with defined transportation engineering criteria. Proper installation will also minimize driver frustrations and encourage safe driving practices.
(C) If a location fails to meet any of the following criteria, the placement of speed humps should not be recommended.
(D) Operation criteria.
(1) The functional classification of the roadway is a local or major local street.
(2) Average weekly daily traffic (AWDT) volumes on the roadway segment are less than 3,000 vpd.
(3) The posted speed limit of the roadway segment is 30 miles per hour (m.p.h.) or less.
(4) The 85th percentile speed measured on the roadway segment exceeds the posted speed limit by 10 m.p.h. or more. This criterion may be waived from dead-end streets.
(5) The roadway segment is fronted by primarily (more than 50%) residential land uses.
(E) Geometric Criteria.
(1) The roadway has a vertical grade of 8% or less.
(2) The roadway segment is paved.
(3) The roadway segment has only 1 moving lane of traffic in each direction.
(4) The section length is greater than or equal to 2 blocks or 12,000 feet.
(5) The width of the street is greater than 18 feet.
(F) General conditions. The following general conditions should also be considered when locating speed humps:
(1) Motorists should have adequate sight distance to react to speed humps.
(2) Speed humps should not be placed over manholes, gate valves, utility vault accesses or other similar features.
(3) If a drainage inlet is near where a speed hump would be placed according to the general spacing criteria, an attempt should be made to locate the hump just downstream of the inlet.
(4) Speed humps should be placed to take advantage of existing street lighting.
(5) Speed humps should not be placed in front of driveways.
(6) Speed humps should be placed at property lines, if possible, rather than directly in front of a residence.
(7) Speed humps are placed perpendicular to the direction of travel.
(8) Speed humps should not be placed within an intersection.
(9) Speed humps should not be placed within a horizontal curve.
(10) When curbs are not present, alternate means should be provided to discourage motorists from driving around the speed hump (Figure 3 attached to Ord. No. 2006-02).
(11) Speed humps should follow the corresponding roadway cross-slope.
(G) Neighborhood support.
(1) (a) Property owners on the roadway segment must be in concurrence with the placement of the speed hump(s) and will be allowed 1 vote of record. Concurrence will be indicated by the signing of a petition to the county designee. The formula for calculating the percentage required for petition acceptance is:
Percent of Lot Owners Supporting the Placement of Speed Humps in the Petition Area = 75 – (.25 (Percent Absentee Lot Owners in Petition Area)).
(b) The petition will clearly state that those signing the petition would accept all warning signs and restricted parking associated with the placement of the speed hump(s).
(2) Prior notification and written comments must also be obtained from local fire, rescue, and police departments, as well as from transit providers and the transportation provider for the local public schools.
(H) Prioritization; implementation.
(1) The county will prioritize pending projects on a fiscal year basis by assigning points to each project. Projects will be scheduled for detailed design and implementation based on their point scores and the capital improvement funds available tor the fiscal year. Points will be assigned as follows:
(a) Speed. Two points will be assigned for every 1 m.p.h. that the 85th percentile speed is above the speed limit for the roadway.
(b) Pedestrian activity and facilities. Ten points will be assigned if the street has no sidewalks; 5 points will be assigned if the street has sidewalks on only 1 side or has discontinuous sidewalks. In addition, 10 points will be assigned for each pedestrian generator along the roadway section, for instance, a school playground, or park, and 5 points will be assigned if the street is designated as an on-road bike route.
(c) Street width. Five points will be assigned if the combination of street width and parking characteristic results in areas of single land, alternating flow.
(2) The street yielding the highest numerical point score will be considered to have the highest priority. The street with the earliest application date will have the highest priority among streets with the same point score.
(3) When a budgeted amount for speed humps has been approved, the county will, starting at the top of the ranking list and proceeding in descending order, determine which installations will be funded from the budgeted amount. Representatives of the applicants for all approved speed hump installations will be notified of which requests have been funded for the upcoming fiscal year.
(4) As funding allows, preference shall be given to those roads qualifying for speed humps for which other improvements are already planned to be constructed.
(I) Exceptions. On roadways which are classified as collectors, an exception may be granted to allow for speed humps if the traffic volume on the roadway is less than 3,000 vpd. The procedure for installation shall remain the same as outlined in this policy. Each case will be reviewed individually and a determination will be made based on consideration of adjacent land uses, function in the transportation system, and safety. In all cases, should speed humps be installed, the speed humps will be removed when the roadway volume exceeds 3,000 vpd.
(Ord. 2006-02, passed 3-17-2006)