4 Wsdot Regions and the Office of Urban Mobility

The roles of planning at WSDOT regions and at the Office of Urban Mobility (OUM) are similar in many ways. What follows are descriptions of the roles of planning at WSDOT regions and the OUM. (a) WSDOT Region Planning. Each WSDOT region has a Planning Office that has several roles, such as Conducting and overseeing special long range planning studies. Coordinating with other planning groups. Assisting in development of prioritized plans. Administering internal WSDOT programs. Performing...

5 Control Equipment

Controller assemblies can be either Type 170 controllers or National Electrical Manufacturers Association (NEMA) controllers with dual ring eight vehicle phase, four pedestrian phase, four overlap, operational capabilities. From a design perspective, identical operation can be obtained from either controller. Specify the Type 170 unless the region's policy is to use NEMA controllers. In situations where it is necessary to coordinate the traffic movements with another agency, it is necessary for...

4Establishment of Vegetation

Most WSDOT projects have 1 to 3 year plant establishment periods. Wetland mitigation projects often include additional years of monitoring to ensure that mitigation standards of success are met. The goal of plant establishment is to promote a healthy, stable plant community. Soil treatments, such as the use of slow release fertilizer incorporation of soil amendments such as compost into the soil layer and surface mulching, may improve the success rate of introduced vegetation. Consult the WSDOT...

33005 Project Definition Phase

Project definition is the initial phase of project development. The project definition effort is prompted by the State Highway System Plan. The project definition phase consists of determining a preliminary project description, schedule, and estimate. The intent is to make design decisions early in the project development process. During the project definition effort, the Project Summary documents are produced. Project Summary provides information on the results of the project definition phase...

71006 Beam Guardrail 1 Beam Guardrails

Standard beam guardrail systems are shown in the Standard Plans. Strong post W-beam guardrail (Types 1 through 4) and thrie beam guardrail (Type 10) are semirigid barriers used predominately on roadsides. They also have limited application as median barrier. Strong post beam guardrail that has been installed incorrectly can cause vehicle snagging or spearing. This can be avoided by lapping the rail splices in the direction of traffic as shown in the Standard Plans, by using crashworthy end...

7 Preemption Systems

Emergency vehicle preemption is provided if the emergency service agency has an operating preemption system. WSDOT is responsible for the preemption equipment that is permanently installed at the intersection for new construction or rebuild projects. The emergency service agency is responsible for preemption emitters in all cases. If the emergency agency requests additional preemption equipment at an existing signal, that agency is responsible for all...

Transitions and Connections

Two-way traffic and, therefore, a terminal is required on the trailing end. Case 10B is used for one-way traffic when there is no need to extend guardrail past the bridge pier and a Type 4 anchor is used to end the guardrail. Case 10C is used for one-way traffic when the guardrail will extend for a distance past the bridge pier. Case 11 (A, B, and C) is used at roadside hazards (such as bridge piers) when the guardrail is to be placed within 1 m of the hazard. Since there is no room for...

2 Terminals and Anchors

A guardrail anchor is required at the ends of a run of guardrail to develop its tensile strength throughout its length. In addition, when the end of the guardrail is subject to head-on impacts, a crashworthy guardrail terminal is required. (See the Standard Plans.) (a) Buried Terminals. The buried terminal (BT) is designed to terminate the guardrail by burying the end in a backslope. The standard BT is the preferred terminal because it eliminates the exposed end of the guardrail. The BT uses a...

Impact Attenuator Sizes

If it is anticipated that a large volume of traffic will be traveling at speeds greater than the posted speed limit, then the next larger unit can be specified. See Figure 720-5 for a summary of space, and initial cost information related to the impact attenuator systems. When considering maintenance costs, anticipate the average annual hit rate. If few impacts are I anticipated, lower cost devices such as inertial barriers might meet the need. Inertial barriers have the lowest initial cost and...

1 Cut and Fill Considerations

Due to the construction technique and base width required, some wall types are best suited for cut situations whereas others are best suited for fill situations. For example, anchored walls and soil nail walls have soil reinforcements drilled into the in-situ soil rock and, therefore, are generally used in cut situations. Nongravity cantilevered walls are drilled or cut into the in-situ soil rock, have narrow base widths, and are also well suited to cut situations. Both types of walls are...

5 Pedestrian Grade Separations

In areas where heavy pedestrian traffic is present and opportunities to cross the roadway are infrequent, consider providing a pedestrian grade separation. When considering a pedestrian structure, determine if the conditions that require the crossing are permanent. If there is a likelihood that the pedestrian activity generator might not exist in the near future, consider less costly solutions. Locate the grade separated crossing where pedestrians are most likely to cross the roadway. A...