Local Stormwater Management.  Stormwater is a primary cause of water pollution in the United States, and as such, has resulted in many federal, state, and local regulations.  Stormwater is runoff that flows into pipes, ditches, streams, and other receiving water bodies.  The Clean Water Act of 1972 established the regulatory framework to address stormwater pollution control through the restoration and maintenance of the chemical, physical, and biological integrity of United States' waters.
 
Local stormwater management is typically provided through a stand-alone governmental utility.  A stormwater utility may be operated by a city or county, and provides stormwater services to a jurisdiction through user fees.  Stormwater management activities may vary depending on a jurisdiction's geographical needs, but often includes the ongoing operation and maintenance of publicly owned stormwater facilities, drainage basin planning, education and outreach, water quality programs, monitoring, and capital improvement projects.
 
Stormwater utilities generate a majority of their revenue through utility rates based on impervious surface area.  Stormwater utilities may also rely on city street funds or county road funds, as well as special assessments, local improvement districts, direct charges and fees, capital facilities charges, or conventional debt instruments.  The revenue generated from stormwater utility rates provide for capital construction of stormwater systems and controls to prevent flooding and improve quality and maintenance and operations.

Diking, Drainage, and Sewerage Improvement Districts.  Diking, drainage, and sewerage improvement districts (districts) are special purpose districts established to improve dikes, drains, sewerages and ditches to provide an efficient system of drainage and flood control for land within the district.  Districts are governed by a board of three elected supervisors, and are authorized to impose assessments on properties within their borders in proportion to the benefits those properties receive from diking improvements and maintenance.  Districts may also impose a one-year regular property tax levy or issue general obligation debt.
 
The districts may provide an array of improvements to the land within the boundaries of the jurisdiction, including:

• construct or improve all rivers, watercourses or streams causing overflow damage, including perform activities that straighten, widen, or deepen such watercourses;
• establish diking and drainage systems or erect flood dams to prevent inundations; and
• plan, construct, and operate facilities to collect, treat, and dispose of sanitary, industrial, and other sewage.

 
In 1985, the Legislature adopted standardized provisions governing districts creation and operation.  Separate statutory provisions continue to apply to diking, drainage, and sewerage districts and their actions. 

A county must consult a district prior to constructing or improving any stormwater control facility within the district's boundaries.
 
A district must accept responsibilities for the maintenance and operation of a stormwater control facility or portion of a facility within the district boundaries.
 
Any revenue generated from county stormwater service charges and rates collected within a district must be deposited into the district's revenue account.  A district may retroactively collect no greater than seven years of service charges and rate revenues from the county treasury.