Pima County enforces stormwater management through the Pima County Regional Flood Control District (RFCD) and the county MS4 permit under the Clean Water Act. The Sonoran Desert monsoon season (July-September) drives strict drainage and retention requirements. All new development must retain the first inch of stormwater on-site per county standards.
The Pima County Regional Flood Control District administers stormwater regulations for unincorporated areas. Under the county MS4 (Municipal Separate Storm Sewer System) permit issued by ADEQ, all construction sites disturbing one acre or more must file an Arizona Pollutant Discharge Elimination System (AZPDES) Notice of Intent and implement a Stormwater Pollution Prevention Plan (SWPPP). The county requires on-site retention of the first inch of rainfall (the 100-year, 2-hour storm standard) for new developments. Green infrastructure practices including bioswales, retention basins, and permeable paving are encouraged. The county participates in the National Flood Insurance Program (NFIP) and maintains detailed floodplain maps through RFCD. Monsoon flash flooding is the primary stormwater concern, with arroyos and washes subject to strict no-build buffers. Contact RFCD at 520-724-4600.
Failure to implement required stormwater controls may result in stop-work orders, permit revocation, and fines up to $10,000 per day under AZPDES. Illicit discharges to storm drains are prohibited and subject to both county code enforcement and state ADEQ penalties. Report stormwater pollution to the RFCD hotline.
Pima County, AZ
Pima County Code §9.30.070 restricts outdoor construction noise to permitted hours. Concrete work: 5 AM–7 PM (Apr 15–Oct 15) and 6 AM–7 PM (Oct 16–Apr 14). A...
Pima County, AZ
Pima County Code Chapter 9.30 and animal control code (Chapter 6.04) cover excessive animal noise. Pima Animal Care Center (PACC) handles barking dog complai...
Pima County, AZ
Pima County Code Chapter 9.30 prohibits excessive, unnecessary, or offensive noise that disturbs the peace or quiet of any neighborhood or causes discomfort ...
Pima County, AZ
Pima County has no outdoor music or amplified sound ordinance for unincorporated areas. ARS 13-2916 applies to unreasonable noise. Event venues may have CUP ...
Pima County, AZ
Pima County Zoning Code Chapter 18.67 regulates fences and walls in unincorporated areas. Front-yard walls max 3 feet in residential zones. Side/rear walls m...
Pima County, AZ
ARS 36-1681 requires 5-ft pool barriers with self-closing, self-latching gates in Pima County. Applies to all pools 18+ inches deep. Door alarms or safety co...
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