How to Get a Septic Permit in Pinal County, AZ (2026 Guide)

By Perc Test AZ · Published July 9, 2026

If you're building on land without a sewer connection anywhere in Pinal County, whether that's San Tan Valley, Casa Grande, Maricopa, Florence, Coolidge, Eloy, Arizona City, or a raw desert parcel in the unincorporated county, you will need a septic permit before you can build. Pinal County's official pages explain the pieces, but there's no single document that walks you through the whole sequence. This guide does.

First, know who you're dealing with. Septic permits in Pinal County are issued by the county's Aquifer Protection Program (part of Community Development), operating under authority delegated by the Arizona Department of Environmental Quality. The county permits conventional systems up to 24,000 gallons per day and alternative systems up to 3,000 gallons per day. The office is at 85 N Florence Street, First Floor, Florence, AZ 85132, open Monday through Thursday, 7:00 a.m. to 5:30 p.m., phone 520-509-3555.

The Short Version: Six Steps to a Pinal County Septic Permit

1. Confirm septic is your only option. No sewer connection available to the parcel, and zoning cleared via the county's Septic Zoning Clearance form.
2. Order the site investigation and perc test. A qualified investigator characterizes the lot under Arizona rule R18-9-A310.
3. Get the system designed. Conventional under the 4.02 general permit if the soil allows, alternative if it doesn't, sized from the tested rates.
4. Submit the Notice of Intent to Discharge. Soil report, design, and zoning clearance go to the Aquifer Protection Program in Florence.
5. Build under the Construction Authorization. Your installer works to the stamped plans with county inspection, within the two-year window.
6. Close out with the Discharge Authorization. Completion paperwork filed; the system is now legal to operate.

Here is each step in detail.

Step 1: Confirm That Septic Is Your Only Option

Pinal County's position is simple: if your property has a sewer connection option, you connect to sewer. If it does not, you apply for a septic permit. Most rural and semi-rural parcels in the county fall into the second category. Before spending money on testing, it's also worth confirming your parcel's zoning allows the intended use; the county's application packet includes a Septic Zoning Clearance form for exactly this reason. If you're unsure whether a sewer line reaches your lot, a quick call to the Aquifer Protection office settles it.

Step 2: Order the Site Investigation and Perc Test

Arizona law requires a soil and site evaluation before any septic system can be designed. The controlling rule, Arizona Administrative Code R18-9-A310, spells out what a qualified investigator must do:

• Percolation testing at multiple locations: at least two test locations in the primary disposal area and at least one in the reserve area, so the county has credible data for both.
• A deep soil profile: limiting conditions (caliche, rock, clay layers, groundwater) must be characterized within a minimum of 12 feet of the surface, or down to an impervious layer if one is hit shallower.
• An absorption rate inside the legal window: the soil absorption rate used for design must fall between 0.20 and 1.20 gallons per day per square foot. Soil that drains slower or faster than that window cannot support a standard gravity system.

The findings go onto the Uniform Site Investigation Report (USIR), the standardized form Pinal County lists in its septic application packet. The county also provides a Site Investigation Notification form, and its fee schedule includes a line item for a county staffer to observe the percolation test in the field. If you want the full technical background on how the test itself works, we cover it in What Is a Perc Test?, and our soil testing service page explains what we do on site.

Step 3: Get the System Designed

The perc data determines which path your design takes:

• Conventional systems fall under Arizona's 4.02 general permit: a septic tank with gravity disposal through trenches, beds, chamber technology, or a seepage pit, for design flows under 3,000 gallons per day. If your soil percs in the acceptable range and the lot has room, this is the simplest and least expensive route.
• Alternative systems fall under the 4.03 through 4.23 general permits and cover technologies like aerobic treatment units, pressure distribution, and engineered sand media. These are the answer when soil, groundwater, or lot constraints rule out a conventional layout.

Either way, the design must identify both a primary disposal area and a reserve area on the plot plan, sized from the measured absorption rate and the number of bedrooms in the home. This is engineering work, and it's the stage where a bad perc report or a cramped site plan comes back to bite. Pinal County reviews the design against the same state rules ADEQ would apply.

Step 4: Submit the Notice of Intent to Discharge (NOID)

In Arizona, the septic permit application is formally called a Notice of Intent to Discharge. Pinal County's version covers general permit types 4.02 through 4.23, and the complete package the county lists in its applications library includes:

• The Notice of Intent to Discharge form
• The Administrative Review Checklist
• The Septic Zoning Clearance
• The Uniform Site Investigation Report with your perc results
• The system design and site plan

Per the county's FAQ, applications are accepted by email or by appointment. On cost: the county's published fee schedule lists a $296 initial fee for a conventional septic tank system permit, $400 initial (up to a $1,000 maximum) for an alternative on-site system, and $94 for the site investigation/evaluation review. Government fees get revised, so treat those numbers as a budgeting baseline and confirm current amounts with the county before you submit.

Step 5: Build Under the Construction Authorization

When the county approves your NOID, it issues a Construction Authorization. Under R18-9-A301, no one may begin building the system before that authorization exists, and once issued, construction must be completed within two years. Your installer excavates and builds the system to the approved plans, and county staff inspect the construction; the initial permit fee covers up to two construction inspections, with a $75 fee listed for additional re-inspections if work gets red-tagged. Deviating from the stamped design without approval is the fastest way to earn one of those.

Step 6: Close Out With the Discharge Authorization

A finished system still isn't a legal system. After construction and inspection, the closeout paperwork goes in: the Engineer's or Licensed Contractor's Certificate of Completion and the Request for Discharge Authorization, both listed among Pinal County's septic inspection forms. Once the county confirms the facility was built to the approved design, it issues the Discharge Authorization, the document that actually permits wastewater to flow. Keep it with your property records; you'll need it when you sell.

How Long Does the Whole Process Take?

No statute guarantees a turnaround, and county review time rises and falls with construction activity. A realistic way to think about it:

• Fieldwork: perc testing and the soil profile take a few hours on site.
• Report and design: Perc Test AZ delivers permit-ready reports within 48 hours of fieldwork; conventional designs follow quickly, while alternative systems take longer because of added engineering.
• County review: varies with workload. Call 520-509-3555 for current estimates before locking a construction schedule.
• Construction window: once authorized, you have two years to complete the build.

The biggest schedule killer isn't the county queue; it's an incomplete or internally inconsistent application that bounces back for corrections. A package where the perc data, USIR, and design all agree goes through review once.

Pinal County Septic Fees at a Glance

From the county's published fee schedule. Government fees get revised, so confirm current amounts at 520-509-3555 before budgeting.

County line item	Fee
Conventional septic system permit (initial)	$296
Alternative on-site system permit (initial)	$400 (up to $1,000 max)
Site investigation / evaluation review	$94
Percolation test observation	$94
Re-inspection after a red tag	$75
Permit transfer at property sale (Notice of Transfer)	$50

Remember these are the county's fees only. The perc test, the design work, and the installation are separate budget lines; our perc test cost guide covers the testing side.

Where Pinal County Projects Go Sideways

Pinal County's geology is not gentle. The failure points we see most often:

• Shallow caliche. Large areas of the county have cemented hardpan within a few feet of the surface. When the investigator hits an impervious layer well above 12 feet, the room for a gravity drainfield shrinks fast, and the design often shifts to a shallow-footprint alternative system.
• Heavy clay. Slow-draining clay soils can perc below the 0.20 gallons per day per square foot floor, which takes conventional disposal off the table entirely.
• Extremely fast soils. Coarse sand and fissured material can exceed the 1.20 cap. Counterintuitively, draining too fast is also a failure, because wastewater reaches groundwater before the soil finishes treating it.
• Missing reserve area. Applications that show a primary disposal area but no tested reserve area don't meet R18-9-A310 and come back for more fieldwork.
• Paperwork gaps. A skipped zoning clearance or an incomplete Administrative Review Checklist stalls an otherwise sound project.

Where a Design-Only Firm Fits In

Perc Test AZ handles the front half of this process end to end: the site investigation, percolation testing, USIR, system design, and NOID package preparation for Pinal County submission. We are a design-only firm; we never bid on installations. That matters twice over. For homeowners, it means our soil findings and system recommendation aren't shaped by what we'd like to build; nobody profits here by steering you into a bigger system. For installers, it means the leads and the install stay yours. We test, design, and hand off a clean approved permit; you build. If your project sits elsewhere in the county, our Pinal County service area page covers the communities we work in, and our septic design cost guide breaks down what to budget for the design side.

Pinal County Septic Permit FAQ