Mesa Plumbing Codes and Permits
Every Mesa plumbing rule we cover, sorted by topic. Each page says what the rule means and links to the official Mesa source.
- Adopted plumbing and gas codes
- 2024 IPC with Appendices C and E (Res. 12453, Ord. 5983), 2024 IFGC (Res. 12455, Ord. 5985) and 2024 IRC (Res. 12451, Ord. 5981), with Mesa amendments, in effect 2026-01-08. Mesa does not use the UPC.
- Where the code is hosted
- Municode, Mesa Code of Ordinances (Title 4 Building Regulations, Title 8 Health, Sanitation and Environment)
- Permit portal
- Mesa E-Permit Online Portal (Accela), Development Services Permit Services 480-644-4273
- Backflow program
- Mesa Water Resources, 480-644-6462, backflow@mesaaz.gov
- Industrial Pretreatment (grease and industrial discharge)
- 480-644-2484, industrialpretreatment@mesaaz.gov
Permits and Inspections
Permits and Inspections in every city- City CodeVerified Oct 2026Mesa City Code 4-1-9; 4-1-8(T); 4-5-3What happens if plumbing work in Mesa breaks the code? City Code 4-1-9 and 4-1-8(T)Mesa treats a violation of its building and plumbing administrative code as a class one misdemeanor: a fine up to $2,500, up to six months in the city jail, or both, with each day a separate offense. Starting work before the permit also triggers a separate unauthorized construction fee of 50 to 200 percent of the permit fee.
- City CodeVerified Sep 2026Mesa City Code 4-1-5(A), (B)2, (B)3, (B)11, (C), (E) and (F), InspectionsWhat plumbing inspections does Mesa require? City Code 4-1-5 rough-in, concealment and finalMesa inspects permitted plumbing in stages. An in-slab inspection comes before concrete, a rough inspection comes before pipe is covered and before fixtures are set, and a final comes when the work is done. The permit holder has to request each inspection and keep the work exposed until it passes.
- PermitVerified Sep 2026Mesa City Code 4-1-4(A), (B)5, (C), (D) and (H)When do you need a plumbing permit in Mesa, and what is exempt? City Code 4-1-4Mesa requires a permit to install, alter, repair, remove or replace a plumbing or gas system. The exempt list is short: stopping leaks and clearing stoppages without changing pipe, reinstalling toilets, water heater and treatment appliance swaps, and equal replacement of the exterior water or sewer line outside the street or a public easement.
Water Heaters
Water Heaters in every cityBackflow Prevention
Backflow Prevention in every city- City CodeVerified Sep 2026Mesa City Code 8-1-13, Termination of Water ServiceCan Mesa shut off your water for backflow violations? City Code 8-1-13Yes. Mesa Water Resources may terminate water service if backflow protection is missing, removed, bypassed or not working, if the annual test or its records are late, or if an unprotected cross connection exists. If the hazard is imminent it can act immediately. Service stays off until the problem is fixed and penalties and fees are paid.
- City CodeVerified Sep 2026Mesa City Code 8-1-6, Plan Review Requirements, and 8-1-7, Facility InspectionsMesa backflow assemblies on building plans, and new inspections when you add equipment: City Code 8-1-6 and 8-1-7Mesa requires each backflow assembly on the plans with its manufacturer, model and size, and the city must approve the installation before the permit issues. Adding or removing equipment that could create a hazard triggers a new inspection within 30 days, and a required assembly goes in within 60 days of the notice.
- City CodeVerified Sep 2026Mesa City Code 8-1-10, Fire Sprinkler Systems; Mesa Plumbing Code 4-5-2 (IPC 608.17.4)Mesa City Code 8-1-10: backflow rules for fire sprinkler systemsMesa requires a double check valve assembly (DCVA) on a fire sprinkler connected only to city water with no additives. Antifreeze, corrosion inhibitors, foam, an auxiliary supply, private hydrants or a combined fire and domestic service call for a reduced pressure assembly (RPA). Existing systems are exempt until modified or a trigger occurs.
- City CodeVerified Sep 2026Mesa City Code 8-1-11 and 8-1-12, Assembly Testing, Maintenance, Repair and RecordsMesa City Code 8-1-11: annual backflow testing, repair deadlines and who can testMesa requires every backflow assembly to be tested and serviced once a year before the city's compliance date, by a Mesa-recognized tester, at the customer's cost. A defect found between tests must be repaired within 15 days, a repaired assembly retested within 24 hours, and each test record filed within 7 days.
- City CodeVerified Sep 2026Mesa City Code 8-1-4, Approved Backflow Prevention Assemblies; Methods, and 8-1-5, Installation RequirementsWhich backflow device fits which hazard in Mesa, and where does it go? City Code 8-1-4 and 8-1-5Mesa matches the device to the hazard: an RPA or air gap for health hazards and backpressure, a DCVA only for non-health hazards, and PVB or SVB for backsiphonage only. Install the service assembly at or near the point of delivery and before the first branch line, at least as large as the service, at the customer's cost.
- City CodeVerified Sep 2026Mesa City Code 8-1-9, Point of Use ProtectionWhich equipment needs its own backflow device in Mesa? City Code 8-1-9 point-of-use rulesMesa requires a backflow device at the equipment itself, not only at the meter. Section 8-1-9 lists the device for each item: an RPA for dental chairs, boilers, car wash gear and carbonated beverage dispensers, a DCVA or dual check for ice makers, and an air gap for sewage pumps. Devices must be tested each year.
- City CodeVerified Sep 2026Mesa City Code 8-1-3 and 8-1-8, Backflow Prevention and Cross-Connection ControlWhich Mesa businesses must have a backflow assembly? City Code 8-1-8Mesa City Code 8-1-8 lists the uses that need a backflow assembly at the service connection, and most commercial ones need a reduced pressure assembly (RPA). Restaurants, medical and dental buildings, car washes, laundries, buildings over three stories and multi-tenant buildings on one service all appear. Two or more listed uses on one service mean an RPA.
- City CodeVerified Sep 2026Mesa City Code 8-1-12, Recognized Backflow Prevention Assembly TestersWho can test backflow assemblies in Mesa? City Code 8-1-12 recognized testersOnly a tester the city recognizes may test or maintain a backflow assembly in Mesa. To be recognized, a tester submits an application, signs the city's tester agreement, proves certification and files a current gauge accuracy report. Equipment must be calibrated every year, and late test records or improper protocol can lead to discipline.
Sewer Lines
Sewer Lines in every city- City CodeVerified Oct 2026Mesa City Code 8-4-5 (private wastewater systems) and 8-4-10(C) (existing septic tanks)Can you keep a septic tank in Mesa? City Code 8-4-5 and 8-4-10(C)Existing Mesa septic tanks may continue while they meet county health standards. New private systems are restricted to cases where the county determines that public sewer is unavailable. An existing septic tank may keep running while it meets Maricopa County health standards, and once the county finds it in violation the owner must connect to the sewer.
- City CodeVerified Oct 2026Mesa City Code 4-5-2, IPC 701.2 Connection to Sewer Required (as amended)Does Mesa require you to connect to the public sewer? Plumbing Code 701.2Mesa's amended plumbing code generally requires public-sewer connection. Existing lawful septic systems also have protections under City Code 8-4-10(C). Only Maricopa County Environmental Services can decide a sewer is not available, and then a private septic system meeting state and county rules is allowed. Tub, shower, bathroom sink and laundry drainage can go to a graywater system instead.
- Local AmendmentVerified Oct 2026Mesa City Code 4-5-2, IPC 305.4.1; Mesa City Code 4-3-2, IRC P2603.5.1How deep must a building sewer be in Mesa? Plumbing Code 305.4.1At least 12 inches below grade. Mesa's amended plumbing code sets that minimum for every building sewer, and requires the same 12 inches below finished grade at the septic tank connection where the sewer serves a private system. The residential code carries a matching 12 inch rule for homes.
Water Supply and Pipes
Water Supply and Pipes in every cityDrains, Traps and Vents
Drains, Traps and Vents in every cityFixtures
Fixtures in every cityWater Conservation
Water Conservation in every cityCommercial Plumbing
Commercial Plumbing in every city- City ProgramVerified Sep 2026Mesa City Code 4-1-4(U), Permit-by-Inspection ProgramCan a Mesa tenant improvement use permit-by-inspection? City Code 4-1-4(U)Small tenant improvements in Group B, M or S space can use Mesa's permit-by-inspection program if they are 10,000 square feet or less, involve no change of occupancy (except between B and M), no high piled storage or hazardous materials, and need no added zoning approval. An inspector reviews and issues the permit. Using it is optional.
- City CodeVerified Sep 2026Mesa City Code 9-1-6, Pavement Restoration Fees, Pavement Cut RestrictionsCan you cut a newly paved Mesa street for a sewer or water repair? City Code 9-1-6Usually not for two years. Mesa's City Engineer will not approve a right-of-way permit to cut a street for two years after the city accepts new pavement, renovation, reconstruction or street maintenance. Exceptions cover emergencies, lost essential service, building service with no other route and legal mandates. Cuts within five years also pay a restoration fee.
- PermitVerified Sep 2026Mesa City Code 4-1-6, CertificatesDo you need a certificate of occupancy to open or change a Mesa business? City Code 4-1-6Yes. In Mesa no building can be used, and no occupancy classification changed, until the Building Safety Director issues a Certificate of Occupancy after inspection. It also waits on unpaid city taxes and accounts. A partial or temporary certificate can cover part of a project, and the original is free.
- PermitVerified Sep 2026Mesa City Code 8-4-8, Building Connections; Permit, Approval, Records, and ResponsibilityDo you need a permit to connect a building to the Mesa sewer? City Code 8-4-8Yes. Any connection to, opening into or alteration of Mesa's public sewer needs a written permit from Development Services, and a valid plumbing permit comes first. The owner maintains the building connection pipe from the building to the public sewer, except that the city repairs a broken section located off-property in a street or alley.
- PermitVerified Sep 2026Mesa City Code 9-1-2, Right-of-Way Permits; 9-1-3, Notification; 9-1-8, Stop Work Orders; 8-4-4, Digging Up StreetsDo you need a right-of-way permit for plumbing work in a Mesa street or alley? City Code 9-1-2Yes. Mesa requires a Right-of-Way Permit before anyone excavates or works in a street, alley or public easement, including sewers and water mains. Apply with engineering plans, and the City Engineer reviews and inspects the work. Give 24 hours notice before starting. Digging a street to connect to the sewer also needs the City Engineer's permit.
- PermitVerified Sep 2026Mesa City Code 8-4-16 and 8-4-18, Class I, II and III Industrial UsersDo you need an industrial wastewater discharge permit in Mesa? City Code 8-4-16 and 8-4-18You need one if Mesa classes your business as Class I (any significant industrial user) or Class II (a smaller user the city finds could harm the sewer or worker safety). Class III needs no permit. Mesa issues permits within 60 days of a complete application, for up to five years, and they cannot be transferred.
- PermitVerified Oct 2026Mesa City Code 8-10-9Does a Mesa business need a Multiple or Large Meter permit? City Code 8-10-9Yes, if you ask for a meter four inches or larger, or the equivalent in multiple meters. Mesa's code also requires an MLM Permit to use more than the 330 acre-foot annual demand ceiling or to take service with unusual demand. Residential-only meters and hospitals are excluded, but landscape meters are not.
- Local AmendmentVerified Oct 2026Mesa City Code 4-5-2, IPC 403.2 Exception 2, Table 403.1 footnote e, and 410.2 (as amended)Does a small Mesa business need separate men's and women's restrooms? IPC 403.2 and 410.2Not if the total occupant load is 25 or fewer, counting employees and customers. Mesa's amendments also drop the service sink requirement for businesses and stores with 100 or fewer occupants and the drinking fountain requirement at 50 or fewer. Other separate-facility exceptions and fixture-count rules still apply.
- City CodeVerified Sep 2026Mesa City Code 8-4-22(E), Interceptor and Grease Trap SizingHow big must a Mesa restaurant grease interceptor be? City Code 8-4-22(E)Mesa sizes a grease interceptor from drainage fixture units: total the units, multiply by 3 gpm, then by 12, and round up. The minimum is 500 gallons, the maximum 2,500, with two chambers, or three at 750 gallons and up. A trap is allowed only with four or fewer food-prep fixtures and no dishwasher.
- City CodeVerified Sep 2026Mesa City Code 8-4-21, Pretreatment; Maintenance of Facilities and BypassKeeping Mesa pretreatment equipment running: City Code 8-4-21 records and bypass rulesMesa makes the owner keep pretreatment equipment in continuous, effective operation at the owner's cost and keep cleaning, repair and calibration records at the facility for three years. Bypasses are prohibited except in narrow cases. A planned bypass needs 10 days written notice, and an unplanned one must be reported within 24 hours.
- City CodeVerified Sep 2026Mesa City Code 8-4-22, InterceptorsMesa City Code 8-4-22: who needs a grease interceptor and what upkeep it takesMesa City Code 8-4-22 lets the city require a grease, oil or sand interceptor at restaurants, laundries, service stations, auto shops and carwashes. The owner keeps it working at their own expense and keeps written cleaning and repair records at the facility for three years. Section 8-4-22 sets no pumping interval.
- Permit FeeVerified Sep 2026Mesa City Code 8-10-13, Capacity Fee, and 5-17-5, Imposition of Impact FeesMesa water and sewer capacity fees for a commercial project: City Code 8-10-13 and 5-17-5Mesa charges a water and wastewater capacity fee by meter size on any new or upsized water connection, from $9,528 for a 3/4 inch meter to $254,072 for a 4 inch meter. It is due before the city installs the meter. Upsizing pays only the difference, and impact fees under Title 5 can apply on top.
- City CodeVerified Sep 2026Mesa City Code 8-4-15, Prohibited Substances and Discharge LimitationsWhat can a Mesa business not put down the drain? City Code 8-4-15 prohibited discharges and limitsMesa bans wastewater below pH 5.0 or above 10.5, hotter than 150 degrees F, with a flashpoint under 140 degrees F, or carrying enough fats, oils, grease or solids to block or damage the sewer. It also bars unapproved cooling water, condensate and stormwater. Class I industrial users face added metal limits.
- City ProgramVerified Sep 2026City of Mesa Plumbing Plan Submittal Checklist; Mesa City Code 4-1-4(I), Submittal DocumentsWhat does Mesa's commercial plumbing plan review checklist require?Mesa reviews commercial plumbing plans against a nine-page checklist built on the 2024 IPC with Mesa amendments. It covers fixture counts, water service, drainage, vents, backflow, roof drains and interceptors. Plumbing systems cannot be deferred to a later submittal, and incomplete packages can be returned without review.
- PermitVerified Sep 2026Mesa City Code 4-1-4(A) exception 7, 4-1-4(F) and 4-1-4(H)(2), Annual Facility PermitsWhat is Mesa's Annual Facilities Permit for plumbing work? City Code 4-1-4(F)Mesa can issue an Annual Facilities Permit to a qualified facility, such as a manufacturer or property manager with full-time building staff. It replaces individual permits for repeat work on existing buildings, but only if the work adds no floor area and does not change the use. An Arizona registered architect or engineer must serve as the agent.
Also in the library: Uniform Plumbing Code · Arizona · Valley-Wide · Maricopa County (unincorporated) · Phoenix · Scottsdale · Paradise Valley · Chandler · Gilbert · Tempe · Glendale · Surprise · Avondale · Tolleson · Litchfield Park
Need It Done To Mesa Code?
Call a licensed plumber who pulls the permit and passes inspection the first time.