Water Resources Research Act Program

Details for Project ID 2011DC123B

GIS-based Ecosystem Service Analysis of Urban Green Infrastructure as a Tool for Attaining Water and Air Quality Objectives in the District of Columbia

Institute: District of Columbia
Year Established: 2011 Start Date: 2011-03-01 End Date: 2012-02-28
Total Federal Funds: $10,100 Total Non-Federal Funds: $4,646

Principal Investigators: Tolessa Deksissa

Abstract: As the result of fast development activities within the District of Columbia and its surroundings, the decline of heavy tree cover and green area in the region is creating a challenge for the attainment of water and air quality objectives of the District. All main rivers, including rock Creek, Anacostia and Potomac Rivers are impaired mainly due to the impact of combined sewer overflows. The decline of green area or pervious area has resulted in increased flow volume of stormwater runoff that exceeds the capacity of the sewer system, and consequently a mixture of raw sewerage and stormwater runoff is being discharged to the receiving waters during as little as a half inch of rain. Despite the fact that ecosystem service is often considered as free goods and services, the estimated cost that the community must pay when the benefit of green area is lost is quite high. It is therefore important to estimate both economic and ecological benefit of green infrastructure in the District, including trees, green roof and other green areas to assess the change of those services over time. The goal of this study is to conduct Geographic Information System (GIS) based ecosystem service analysis of green surfaces in the District of Columbia. The objective of the study is three folds: (1) geo-coding the green area as well as gray area, (2) ecological benefit analysis of those green areas, including trees, green roof, and open surfaces, and (3) determine the effects of future land cover change on the Districts EPA attainment levels of air and water quality. The proposed ecosystem service analysis will be conducted using the GIS technologies with spatial analysis capability and the CITYgreen. In the CITYgreen modeling tool, three sub-models are integrated, such as stormwater runoff and water quality and air pollution. The result of such geo-referenced analysis of ecosystem service provides valuable benefit to the district for attaining water and air quality objectives. In the proposed approach, in addition to aesthetic values, integrating economic as well as ecological values of the green infrastructure in urban set, such as carbon sequestration, reducing energy use in the building, storm water management, can help the decision makers meet water and air quality objectives as well as mitigate climate change.