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• Echlb'd- Open s ace through stor p managazuenticT Helping to structure growth on the urban fringe Many current events described in the media point to the continua- . tion of a past trend: like it or not, most future growth will continue to occur in the suburbs. At subdivision and land development review meetings, one of the most frequently discussed topics is stormwater management. Unimaginative engineering approaches to stormwater management, though, often leave subdivi- sions pockmarked with city depressions in remote corners collecting debris, while re- maining "on standby" to control runoff from rare storm events. The costs are borne by future home buyers, but the ob- jectives of protecting water resources and reducing flooding downstream are not fully realized. This article advocates a holistic approach that views stormwater as a vital part of the hydrologic cycle involving management practices to insure infiltration, control runoff pollution, reduce thermal impacts and con- trol peak flows. Management practices for this kind of control put the landscape to work by utilizing processes of nature such as vegetative filtering during conveyance, cooling through shade trees, detention through depression storage, and infiltration. When implemented in settings that prior to the introduction of impervious surfaces did not experience much runoff, such manage- ment practices can be designed to form sys- tems that function as an extension of the ex- isting riparian landscape. The public is beginning to accept that bodies of water, wetlands, and floodplains are best used as permanent open space, protected through land use controls. These open spaces follow stream valleys and can be expanded and en- hanced through stormwater management practices on adjacent development sites (Fig- ure 1). Such management practices are also open space features and are designed in accor- dance with performance standards. Stormwater management measures and ri- parian lands can be integrated to form a 14 JOURNAL OF SOIL AND WATER CONSERVATION J. Toby Tourbier functional riparian "greenway" or open space system. When viewed comprehensive- ly, stormwater management offers an oppor- tunity to structure the present pattern of en- vironmentally destructive sprawling subdivisions known as -the suburban model," and provides as a bonus the protec- tion of vegetation and wildlife. The responsibility for accommodating land use and related stormwater manage- ment measures lies with municipalities who execute a review and approval process that is guided by subdivision and land develop- ment ordinances. Housing is expected to be the rust component of the economy to re- spond to the long awaited upturn from the current recession. Municipalities now have an opportunity to formulate an approach en- abling stormwater management to function as a tool to help structure growth that is cer- tain to occur. The stormwater concern Stormwater management had its origin.in what was known in legal language as the "common enemy rule ": draining runoff away from houses and backyards as fast as possi- ble. As populations grew, this practice proved to be detrimental because one per- son's backyard drained into someone else's front yard. The runoff then accumulated, re- sulting in flood damage downstream. For many years the federal government was heavily involved in flood control, only to discover an ever - increasing spiral of expen- ditures, but still mounting flood losses. Today, the pollution associated with runoff is an additional concern. The first flush of urban runoff from cities such as Washington, D.C., was found to be as polluted as raw sewage, due to paved surfaces collecting phosphorous -rich dust, nitrogen from acid rain, and automobile related trace metals. Urban and suburban runoff today is the sin- gle biggest source of water pollution, limit- ing the full use of one third of the nation's waters (6). In October 1992 the U.S. Envi-