Environmental Rules in Tempe, AZ

If you live in Tempe or are thinking about moving there, environmental rules are one of those things you probably won't think about until they affect you directly. Tempe has 4 specific rules on the books covering different aspects of environmental rules, and some of them might surprise you.

Stormwater Management

Tempe bans discharging anything but storm water into the public storm drain system under Chapter 12, Article VI of the general code. Section 12-115 sets the purpose: cutting pollutants from spills, dumping, and improper storage to meet the City's federal Clean Water Act and state AZPDES storm water permits, with the Public Works Director enforcing prohibitions, inspections, and civil penalties up to $2,500 per violation per day.

Key details: Discharge rule: Only storm water may enter public storm drains. Enforcing agency: Public Works Director (§12-115, §12-123). Spill notice deadline: Phone within 24 hours, writing within 3 days. Civil penalty cap: $2,500 per violation per day (§12-149). Criminal penalty: Class one misdemeanor, up to 6 months jail.

Violating the storm water pollution control article can draw a civil citation carrying up to $2,500 per violation per day under § 12-149(c), plus a default penalty of up to $50 if a defendant skips their court date. Willful or negligent violations are prosecutable as a class one misdemeanor under § 12-151, punishable by a fine up to $2,500 per day, up to six months in jail, or both, and the City can also seek an injunction through Maricopa County Superior Court.

This is not one of those rules that cities tend to ignore. Tempe actively enforces its stormwater management requirements.

Flood Zones

Any grading, construction, fill, or manufactured-home placement inside a Special Flood Hazard Area shown on Tempe's FEMA flood maps needs a floodplain permit from the City Engineer before Community Development issues a building permit. Tempe City Code § 12-16 frames flood-loss prevention as the article's purpose, and § 12-27 spells out what the permit application must show, including lowest-floor elevation and floodproofing certification for non-residential buildings.

Key details: Permit needed: Before any SFHA construction or fill (§12-27). Floodplain Administrator: City Engineer (Tempe City Code §12-18). Effective flood maps: FIRM panels dated September 18, 2020. Correction window: 30 days after written notice of violation. Penalty: Misdemeanor prosecution under Code §1-7.

Development in an SFHA without the written authorization required by A.R.S. § 48-3613 is unlawful under § 12-25. The City Engineer must notify violators by certified mail or personal service, and an uncorrected violation after thirty days is referred to the City Attorney for prosecution as a misdemeanor under § 1-7. Unpermitted flood-hazard-area development is also declared a public nuisance per se that the City can abate, and the Floodplain Administrator may ask FEMA to deny federal flood insurance on the property.

Compared to other cities, Tempe takes a harder line on flood zones. The enforcement and penalty structure reflects that.

Flood Elevation Requirements

Tempe requires new construction in a Special Flood Hazard Area to sit at or above the Regulatory Flood Elevation (RFE), a City-only standard one foot higher than FEMA's base flood elevation. Tempe City Code § 12-18 defines the RFE, and § 12-29(3)(a) requires residential lowest floors, including basements, to be elevated to or above it, with a registered engineer or surveyor certifying the finished elevation to the Floodplain Administrator.

Key details: RFE defined: Base flood elevation plus 1 foot (§12-18). Residential floor: Lowest floor elevated to or above RFE. AO zone minimum: 2 feet above highest adjacent grade. Non-residential option: Floodproof watertight below RFE instead. Certification required: Registered engineer or surveyor, verified by inspector.

A structure or development lacking the elevation certificate or other proof of RFE compliance required by this article is presumed in violation under § 12-25's definition of 'violation,' shifting the burden to the owner to prove compliance. Enforcement follows the same track as other floodplain violations: written notice, a thirty-day correction period, referral to the City Attorney for misdemeanor prosecution under § 1-7, and treatment of the noncompliant structure as a public nuisance per se.

Erosion Control

Anyone doing construction work in Tempe must use temporary and permanent best management practices to keep pollutants and sediment from leaving the site, under general code § 12-128. The rule folds into the City's broader storm water program: builders can't cause a § 12-125 discharge violation and must follow any written BMP guidance from the Public Works Director or Community Development Director, with a ten-day window to petition for reconsideration.

Key details: Who's covered: Any person performing construction (§12-128). Core duty: Use BMPs to keep sediment on site. Related rule: Also can't violate §12-125 discharge ban. Reconsideration window: 10 working days to petition a BMP order. Director response time: 30 days to act on petition.

A construction site that lets pollutants or sediment leave the property in violation of § 12-125 can draw the same Division 5 enforcement as any storm water violation: a written notice of violation, a civil citation of up to $2,500 per violation per day under § 12-149, or misdemeanor prosecution under § 12-151 carrying up to six months in jail for willful or negligent noncompliance.

The Bottom Line

Tempe is tougher than many cities when it comes to environmental rules. Out of the 4 rules covered here, 2 are rated strict. If you are a homeowner, renter, or business owner in Tempe, take the time to understand these requirements before they become a problem. Most violations come with fines, and some repeat violations can escalate.

All of the above reflects Tempe's municipal code as of our last review. If you need specifics on fines, exemptions, or filing requirements, the detailed ordinance pages linked above have the full breakdown.