The draft guidelines released by the EPA on March 22 endorse, among other practices, the installation of porous pavement and green roofs on federal lands in the Chesapeake Bay watershed –recommendations apparently unaffected by heated debate in Annapolis about how to handle the troubled bay ecosystem.

Cisterns for collecting and reusing rainwater as well as added vegetation were also recommended in the EPA guidelines.  According to the guidance draft, these practices were chosen “based on known performance data and cost.”

Low-Impact Development (LID) technology, according to the EPA, “…is now well-proven and shown to be adaptable for implementation at new development, redevelopment, and retrofit sites.” The guidelines also state that LID practices are “necessary to achieve the goals of protecting and restoring the Chesapeake Bay.”

These recommendations fall under stormwater management, one piece of the bay restoration puzzle, which also includes changes in agricultural and political practices. The guidelines are still a draft, subject to additional scrutiny and comment from the public and private sectors of the watershed during the next month.

Citing practices taken in 2004 by the City of Portland, Ore., the draft lists the following conservation guidelines:

• Fitting development to the terrain to minimize land disturbance
• Confining construction activities to the least area necessary and away from critical areas
• Preserving areas with natural vegetation (especially forested areas) as much as possible
• On sites with a mix of soil types, locating impervious areas over less permeable soil (e.g., till), and trying to restrict development over more porous soils (e.g., outwash)
• Clustering buildings together
• Minimizing impervious areas
• Maintaining and using the natural drainage patterns