by George R. Frantz, AICP, ASLA
Stormwater management approaches in the US are evolving dramatically. For most of the past three decades, the standard approach was to store water and control its rate of runoff into the environment. In the past decade, the treatment of stormwater for urban runoff pollutants has gained traction as the impact of such pollutants has become apparent. Throughout the country, developing green infrastructure to treat stormwater pollution is moving from the fringe of the practice to mainstream acceptance.
New York strongly encourages the adoption of green infrastructure approaches to stormwater management to reduce urban runoff pollutants. The New York State Stormwater Management Design Manual released in 2015 sets as design objectives (1) the capture and treatment the full water quality volume of runoff; ( 2) the capacity to remove 80 percent of total suspended solids (TSS) and 40 percent of total phosphorous (TP); (3) mechanisms for the pre-treatment of stormwater; and (4) an acceptable operational lifespan for stormwater systems.
One issue that New York and other states and municipalities fail to address, however, are regulations that dictate a hodge-podge of small, privately owned and maintained (or not) stormwater management systems. General regulatory practice is that stormwater must be managed and treated on the parcel that generates it. This has resulted in a landscape of single-function detention or retention “craters” in developed areas, with little aesthetic appeal or function beyond stormwater management.