Waterloo, IA Environmental Rules: Stormwater Management (2026)

The Waterloo City Council created the stormwater management program to meet federal Clean Water Act and NPDES phase II permit mandates for reducing pollution in runoff (City Code section 8-4-2). The entire city is designated a stormwater drainage system district under Iowa Code section 384.84, governed by a stormwater management authority chaired by the city council and run day-to-day by the City Engineer (section 8-4-5). Every customer whose property connects directly or indirectly to the stormwater system pays a monthly user fee billed on the Waterloo Water Works schedule, funding operation, maintenance and improvement of the drainage system (section 8-4-7).

Fees are set per Equivalent Residential Unit (ERU): the City Engineer calculates ERUs from aerial photography and site plan impervious-surface data, with 5,000 square feet of impervious surface counted as one ERU. Duplex units count as two single-family ERUs and each unit in a multiple-family building counts as one. Properties that add impervious area after a fee ordinance are billed once construction is substantially complete, while demolishing a structure or removing impervious area can qualify a property for a fee reduction. The City Engineer, bearing credentials, may enter private property at reasonable times to inspect, sample and test stormwater discharges under section 8-4-6, and can seek legal remedies if entry is refused. Section 8-4-13 bars damaging drainage structures, entering manholes without authorization, or connecting a private stormwater system to the city's system without City Engineer approval.