Glossary of Terms

Commercial Unit – a utility billing classification used to describe other developed land such as commercial, industrial, and non-profit properties (including churches, schools, land, and community service organizations).

Equivalent Residential Unit (ERU) – a unit of measurement for determining the stormwater utility fee for detached dwelling unit properties and other developed properties. For Alcoa, one ERU equals 2,696 square feet.

Exempt Properties – a utility billing term used to describe properties in the city that are exempt from paying a stormwater utility fee.

Impervious Surface –surface areas that do not absorb rainfall resulting in stormwater runoff (i.e. roofs, patio areas, driveways, parking lots).

Residential Unit – a utility billing classification used to describe detached dwelling unit properties and multiple dwelling unit properties.

Runoff – rainwater that may be mixed with pollutants (oil, detergents, pesticides, fertilizers, sediments) that flows across impervious surfaces, travels through a drainage system, and ends up in our streams and rivers.

Stormwater – the flow of water that results from precipitation and occurs immediately following rainfall or as a result of snowmelt.

Stormwater Utility Fee – a fee calculated based on the amount of impervious surface area on a property. See the Fee Schedule page.

Stormwater Utility Fee Credits – a discount on stormwater fees for Commercial Units that complete an application and documentation describing best management practices that qualify based on the proportional benefit to the stormwater system. (i.e. stormwater/environmental curriculums for Alcoa City Schools).