Government Drainage Regulations and Design Criteria
by Edwin Friedrichs, PE, PTP
Sourcing drainage regulations and design criteria can be challenging as there is no standardized way governmental entities store this information. In fact, most public agencies have regulations spread out across several different documents. In this article, you will learn common sources for this material. It is important to check with the governmental entity to ensure you have the correct edition of the design standard as design manuals are updated on a regular basis and all entities do not always use the latest edition of national or international design standards and codes.
Most local governmental entities have design criteria in a “Design Manual,” sometimes referred to as an “Infrastructure Design Manual.” This is most likely where you will find regulations related to storm water system and drainage design standards and storm water quality design requirements. Some governmental entities reference other governments’ design standards or design standards developed by national organizations such as the American Public Works Association (APWA).
If the local governmental entity is responsible for oversight of the Federal Emergency Management Agency’s Flood Insurance Program as the floodplain administrator, it is likely that they have a special section in their code of ordinances regarding development within the floodplain. These regulations primarily relate to requirements for setting the elevation of a structure’s finished floor and other requirements for development in the floodplain.
Governmental entities that issue permits for construction typically reference a standard building code such as the International Building Code (IBC) and the International Residential Code (IRC). It is common for entities to have their own “amendments” to these codes that are different than the information contained in the standard code. These codes typically have additional criteria related to required finished floor elevations and other floodplain and general drainage development requirements.
Many governmental agencies charge fees which are often dedicated sources of funding for the construction, operation, and maintenance of drainage infrastructure. Some charge a Drainage Impact Fee, a monthly Drainage Utility Fee, or both. Information regarding fees can normally be found by searching the agency’s website using key words such as “Drainage Fee,” “Drainage Impact Fee,” “Watershed Impact Fee,” and “Detention Fee.”