Key Concepts

Changing a Designated Use: Feasibility of Controls

A designated use is considered attainable if:

• It is an existing use, or
• It can be attained with
  • technology-based controls for point sources
  • cost-effective and reasonable best management practices (BMPs) for non-point sources

A designated use is considered not attainable if:

• It is not an existing use, AND
• Attaining the use is "not feasible" because of at least one of the six factors listed in 40 CFR 131.10(g)

An existing use is defined by the Water Quality Standards regulation as those uses actually attained in the water body on or after November 28, 1975, whether or not they are included in the water quality standards (40 CFR 13 1.3). See also Existing Uses in Module 2.)