In traditional administrative law, agencies pass rules and courts review them. But what if agencies stopped acting by rule and started leading by example? The federal response to agricultural water pollution offers a case study in how this increasingly popular form of administration can work, by regulating not through rule, but through suggestion--specifically suggestion via best practices.

As most environmental observers know, runoff remains the most serious and least regulated form of water pollution in the United States. Of the principle sources of runoff pollutants, agricultural runoff is the most notable. The U.S. Environmental Protection Agency (EPA or Agency) has concluded that "[a]griculture is the leading source of pollutants in assessed rivers and streams, contributing to 59[%] of the reported water quality problems and affecting about 170, river miles."

But runoff, be it agricultural or any other kind, is treated differently than the other forms of water pollution addressed by the Clean Water Act (CWA). The CWA only imposes specific federal limitations on pollution from point sources, which are defined as "any discernible, confined[,] and discrete conveyance." Nonpoint source pollution includes everything else and, to the consternation of many observers, it has never been subject to federal prohibition.