The Staten Island Bluebelt: A Case Study in Urban Watershed Management

摘要

By the early 1990s, southern Staten Island was in desperate need of a drainage infrastructure. Asrnthe last significant part of New York City without any formal storm or sanitary system, the arearnwas plagued by flooded streets and polluted streams caused by failing septic systems. But SouthrnRichmond, as the area is known, is also home to the city’s last great stand of freshwaterrnwetlands. Since a conventional piped system would have permanently drained these protectedrnwaterways, the New York City Department of Environmental Protection created a program thatrnincorporated the existing wetlands into the overall drainage network. Using Best ManagementrnPractices (BMPs) as tools for conveying, storing, and filtering stormwater, the approach wasrnapplied over 10,000 acres covering 16 watersheds, collectively known as the Bluebelt.rnNow in its eleventh year, the program has constructed over 50 BMPs while providing the arearnwith almost 100 miles of storm and sanitary sewer. As one of the largest projects of its kind inrnthe Northeast, the Bluebelt contains a history of critical decisions that provide instruction onrnurban watershed management. One of its best examples is the Blue Heron watershed, completedrnin 2004. Covering 322 acres of suburban terrain, the watershed features seven BMPs, includingrnfour constructed wetlands, two outlet stilling basins, and one stream restoration, along with 5 ?rnmiles of storm piping and 10 miles of sanitary sewer. This paper will focus on choices made inrnthe development of its drainage network, including planning issues such as permitting andrninteragency coordination; design topics like hydraulic modeling, bioengineering, landscaping,rnand erosion control; construction issues such as scheduling and sequencing; and maintenancerntopics such as perimeter treatment and accessibility. The paper will conclude withrnrecommendations for improving the implementation of BMPs in an urban environment.