395 - GSA Development of St. Elizabeths Campus

The purpose of this TTR document is to provide detailed technical information and analysis forreference by two separate regulatory approval documents: the new St. Elizabeths Master PlanAmendment EIS and the anticipated Interchange Justification Report. This TTR evaluatestransportation impacts associated with DHS Headquarters consolidation at St. Elizabeths, asproposed in the Master Plan Amendment EIS, and specifically assesses impacts associated withmodifications to I-295. As such, the TTR is an appendix of the EIS document. The TTR will alsobe used as supporting documentation included in the upcoming Interstate Justification Report(IJR) that must be produced to secure approval for a modification in access to the interstate at I-295 / Malcolm X Avenue interchange, as required by DDOT and FHWA.The TTR Study Area, referred to as the Interstate Access Approval Impact Area in the EIS,encompasses a total of 46 intersections and freeway segments in the vicinity of the St. ElizabethsCampus. The sub-set Study Area analyzed in the EIS includes 32 of the 46 intersections studiedin the TTR and is referred to as the EIS Transportation Analysis Study Area. The EISTransportation Analysis Study Area only includes intersections and freeway segments directlyassociated with the proposed action and impacted by the DHS Headquarters consolidation atSt. Elizabeths. This smaller Study Area is generally bounded by the Frederick DouglassMemorial Bridge to the north, the MLK Jr. Avenue intersection with South Capitol Street to thesouth, I-295 to the west, and Alabama Avenue/Stanton Road intersection to the east.1.3 Data SourcesTube count data was collected at 42 segment and ramp locations along Anacostia Freeway,Martin Luther King Jr. Avenue, South Capitol Street, Firth Sterling Avenue, Suitland Parkway,Alabama Avenue, and Malcolm X Avenue. Vehicle turning movement counts were collected for35 of the initial 46 intersections considered during the AM and PM periods - four hours in themorning (5:30 – 9:30 AM) and four hours in the afternoon-evening (3:00 – 7:00 PM). Recenttraffic counts collected for AM/PM peak periods under a separate contract were used at 11 ofthe intersections. Intersection count locations are shown in Figure 3-2.Additional data obtained and collected for use in the study includes:• Travel time runs along limited access facilities and arterials listed above• Base conditions VISSIM model results (existing conditions)• Existing data including mapping, aerials, GIS, land use (existing and future), etc.• Existing signal timings (DDOT)• South Capitol Street Synchro network• Field signal timings• Existing transit data (routes, ridership, projections) provided by Washington MetropolitanArea Transit Authority (WMATA) and Fairfax Connector1-9