SCOPE_OF_WORK.docx

PROPOSED SCOPE OF WORK

Arlington Memorial Bridge Traffic Modeling to Support User Cost Analysis

Purpose Significant structural work is necessary on the Arlington Memorial Bridge. The planned project predominately consists of the rehabilitation of the concrete arch approach spans, and the rehabilitation and/or replacement of Bascule span. Such work requires long-term closure on one or more existing traffic lanes on the bridge. Several alternatives have been developed and are currently under study, including a comparative life cycle cost analysis. The life cycle cost analysis includes a user cost component among other factors. A user cost analysis entails the determination of total vehicular delay and a corresponding cost per unit delay.

Given the level of usage and network connectivity of this bridge, coupled with the recurring traffic congestion in the study area, prediction about future travel conditions under long-term lane closure scenarios warrants use of a regional traffic model. As such, the Eastern Federal Lands Highway Division (EFLHD) of the FHWA is seeking technical services from the Metropolitan Council of Government’s Transportation Planning Board (TPB) to produce an analysis of these conditions through computer modeling.

The purpose of this traffic modeling work is to determine the effect on vehicular travel within the primary study area upon the various construction staging associated with the construction alternatives. The performance measures sought are the following:

· number of diverted vehicles

· representative vehicular travel delay by type of vehicle (passenger cars, buses, trucks)

· traffic maintained on the bridge,

· traffic diverted from the bridge,

· other traffic affected by traffic delayed on or diverted from the bridge

· increase in VMT For the purpose of this analysis, the primary study area should include the alternative river crossings and associated major streets and highways on both sides of the bridge (in Virginia and the District of Columbia) that would define the alternate routes. The extent of this affected area should be determined as part of the modeling analysis.

Scenarios The following table summarizes the long-term lane closure scenarios for the build alternatives followed by a brief description for each alternative currently being considered.

The start of construction on all alternatives is assumed to be March 2016. All days noted are calendar days (i.e., duration).

TABLE: Lane Closure Scenarios (days)

Alternative Initial Stage(s) 2 Lanes Closed Full Closure Stage All Lanes Closed Subsequent Stage(s) 2 Lanes Closed Total Duration

Alternatives 1 & 2:

a) Closure of two traffic lanes (1 westbound lane and 1 eastbound lane) for a period of 65 days, followed by

b) a full closure for a period of 50 days, followed by

c) closure of two traffic lanes (1 westbound lanes and 1 eastbound lane) for a period of 620 days.

Alternative 3:

a) Closure of two traffic lanes (1 westbound lane and 1 eastbound lane) for a period of 65 days, followed by

b) a full closure for a period of 80 days, followed by

c) closure of two traffic lanes (1 westbound lanes and 1 eastbound lane) for a period of 620 days.

Alternative 4:

a) Closure of two traffic lanes (1 westbound lane and 1 eastbound lane) for a period of 65 days, followed by

b) a full closure for a period of 100 days, followed by

c) closure of two traffic lanes (1 westbound lanes and 1 eastbound lane) for a period of 1,095 days.

Alternatives 5:

Closure of two traffic lanes (1 westbound lane and 1 eastbound lane) for a period of 1,548 days Technical Approach EFLHD proposes holding a meeting to discuss this need for TPB services upon TPB’s review of this project statement within one week from this transmittal. The intent is to discuss potential model outputs and applicability to support the User Cost analysis, further information needed to support the analysis, TPB’s recommendations, and TPB’s cost and availability to perform the analysis.