Skip to content U.S. Department of Transportation/Federal Highway AdministrationU.S. Department of Transportation/Federal Highway Administration

Office of Planning, Environment, & Realty (HEP)
PlanningEnvironmentReal Estate

HEP Events Guidance Publications Awards Contacts

WOODROW WILSON BRIDGE PM2.5 CONFORMITY ANALYSIS

Built and Natural Environment

The project area is characterized primarily by a mix of residential, commercial, industrial and parkland uses. Land use development in the project area is governed by multiple layers of planning authorities including the City of Alexandria, Fairfax County, District of Columbia (D.C), and Maryland-National Capital Park and Planning Commission on behalf of Prince George's County. The built environment on the eastern side of the project area (in Maryland and D.C.) is more homogeneous than the western (Virginia) portion. On the eastern shore, there are large tracts of waterfront parkland (the historic 512-acre Oxon Cove Park/Oxon Hill Farm), utilities, and institutional uses, while the land use pattern in Alexandria and Fairfax County is more diverse. There, dense residential and commercial uses extend to the waterfront as do industrial uses and parklands. The most prominent parkland on the western shore is the 64-acre Jones Point Park (traversed by the elevated bridge). See Figure 3-4 in the 2000 FEIS for a depiction of existing land use in the project area.

There are several master and comprehensive plans in place that govern land use patterns and development in the project area. These were described in the 1997 FEIS, Section 3.3 and were updated in the same section of the 2000 FEIS. According the plans described in the FEIS, underutilized land is proposed to be redeveloped into large-scale mixed-use commercial/retail and hotel developments on several sites on the eastern side of the Potomac River (the largest being the redevelopment of DC Village east of I-295). On the Virginia side of the Potomac River, formerly commercial and industrially-zoned land will be redeveloped for mixed-use or high-density commercial uses.

Future Scenario

As shown previously in Figure 4, direct PM2.5 emissions are expected to substantially decrease in future years for the entire nonattainment area. This predicted decrease in emissions is due in large part to EPA's "Heavy-duty Engine and Vehicle Standards and Highway Diesel Fuel Sulfur Control Requirements - Final Rule," signed in December 2000. According to this rule, particulate matter emission levels are expected to be 90% lower on a per vehicle basis in 2030 than they were in 2000.

Figure 6 ­ 24-Hour PM2.5 Monitored Values (98th Percentile), Muirkirk Monitor
Bar graph showing monitored values (98th Percentile) of 24-hour PM2.5 emissions from the Muirkirk monitor.  The values are 38, 32, and 23 μg/m3 for 2004, 2005, and 2006, respectively. A reference line showing the 24-hour PM2.5 NAAQS (65 μg/m3) is drawn across the top of the chart.
Note: 2006 values based on partial year results.


Figure 7 ­ Annual PM2.5 Monitored Values, Muirkirk Monitor
Bar graph showing monitored values of the annual PM2.5 emissions from the Muirkirk monitor.  The values are 12.6, 13.4, and 10.4 μg/m3 for 2004, 2005, and 2006, respectively. A reference line showing the annual mean PM2.5 NAAQS (15 μg/m3) is drawn across the top of the chart.
Note: 2006 values based on partial year results.


Figure 8 ­ 24-Hour PM2.5 Monitored Values (98th Percentile), Franconia Monitor
Bar graph showing monitored values (98th Percentile) of 24-hour PM2.5 emissions from the Franconia monitor.  The values are 33, 35, and 36 μg/m3 for 2004, 2005, and 2006, respectively. A reference line showing the 24-hour PM2.5 NAAQS (65 μg/m3) is drawn across the top of the chart.


Figure 9 ­ Annual PM2.5 Monitored Values, Franconia Monitor
Bar graph showing monitored values of the annual PM2.5 emissions from the Franconia monitor.  The values are 13.2, 13.9, and 13.7 μg/m3 for 2004, 2005, and 2006, respectively. A reference line showing the annual mean PM2.5 NAAQS (15 μg/m3) is drawn across the top of the chart.

Results

Based on the year of expected peak emissions it was determined that the project opening year, 2008, represents the year for the potential worst case impacts of the project. In addition, an analysis of truck percentages and overall 2008 Build AADTs, determined that the area affected by the MA-5: I-295 HOV ramps phase represents the worst case analysis area of the remaining project phases.

Based on the site characteristics of the eleven PM2.5 monitoring stations located in the DC-VA-MD area, it was determined that the Muirkirk monitor has the most similar characteristics to the proposed project. As shown in Table 4, these characteristics include overall traffic volumes and truck volumes that are higher than those predicted near the project's worst case analysis site (e.g., 24,288 trucks near monitor as compared to 19,542 trucks in study area). A conservative approach was applied and the Muirkirk monitor has been used as the representative monitor for this analysis.

Values collected at the Muirkirk monitor in 2004 and 2005, as well as at the Franconia monitor from 2003-2005, did not violate the PM2.5 NAAQS (annual or 24-hour). The 2008 project truck impacts on a per vehicle basis should be less than currently observed at this monitor, based on the implementation of national diesel engine and diesel sulfur fuel regulations that are expected to cut heavy-duty diesel emissions. It may also be noted that control programs for other sources of PM2.5 in the region, geared toward meeting the 2010 attainment date for the PM2.5 standard, are likely to improve air quality in the project area.

Table 4
Summary of Traffic Conditions at Analysis Site, Muirkirk Monitor
Description AADT Truck Percentage Trucks per day
MA-5: I-295 HOV Ramp Project 244,275 8% 19,542
Muirkirk Monitor 303,6000 7.9% 24,288
Franconia Monitor 216,500 6.2% 13,423
Updated: 07/06/2011
HEP Home Planning Environment Real Estate
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000