Stormwater system

Before any statute says what a stormwater system is for, the local and federal codes say what it is made of, and the two lists are nearly the same.

• Collier County Code Sec. 54-65 defines the Stormwater Management System as "either or both of the public or privately owned systems of conveyances including roads with drainage systems, detention ponds, retention ponds, catch basins, curbs, gutters, ditches, man-made channels, or storm drains designed or used for collecting, storing, treating, and/or conveying Stormwater."
• The federal rule, 40 CFR 122.26(b)(8), defines a municipal separate storm sewer as "a conveyance or system of conveyances (including roads with drainage systems, municipal streets, catch basins, curbs, gutters, ditches, man-made channels, or storm drains)" that is owned or operated by a public body and designed or used for collecting or conveying storm water.
• The same federal paragraph goes on to exclude a combined sewer and a part of a publicly owned treatment works from that definition.

The water the system is built for is narrow in both codes. Collier's ordinance defines Stormwater as "the water that results from a rainfall event", and the federal rule defines storm water as "storm water runoff, snow melt runoff, and surface runoff and drainage." Everything else that gets in is a different matter, and what may not enter the system is the subject of the illicit discharge entry.

One difference between the lists is ownership. The county's definition covers public or privately owned conveyances, while the federal municipal separate storm sewer is one a State, city, county, district or other public body owns or operates. Grassy swales, which FDEP's washing guidance lists beside stormwater drains and ditches, have their own swale entry.

A local page shows the system in operation: the City of Naples' archived Streets and Stormwater page says the city's collection system is a Municipal Separate Storm Sewer System, or MS4, covered under an NPDES Phase II MS4 permit.

The state statute skips the list of parts and defines the system by its job. Florida Statutes 403.031(18) says a stormwater management system “means a system designed and constructed or implemented to control discharges that are necessitated by rainfall events, incorporating methods to collect, convey, store, absorb, inhibit, treat, use, or reuse water to prevent or reduce flooding, overdrainage, environmental degradation and water pollution or otherwise affect the quantity and quality of discharges from the system.”

Florida Statutes 373.403(10) carries a near-identical definition, with small differences in wording and punctuation. The two say the same thing but are not interchangeable as text, which is why only one is quoted here.

Read beside the county's list, the statute names the job and the county names the parts: the county's system is designed or used for collecting, storing, treating or conveying Stormwater, and the statute's purpose is to prevent or reduce flooding, overdrainage, environmental degradation and water pollution. The same section defines "Pollution" separately, in 403.031(11).

On an exterior cleaning job the system comes up as a destination for water. The drain-side question for a wash's rinse has its own answer, does the wash water go into the storm drain, and the county washing rule that says where that water must drain is quoted in the Florida rules for a roof cleaning. Who maintains the drains, ponds or ditches at a particular address is a question for the county or the city, not for a definition.