Protect Your Neighborhood's Water

Irrigation Water Delivery Districts in Maricopa County

Many of the Valley's neighborhood irrigation systems are 60 to 80 years old, and they're failing faster than neighbors can pass the hat. An IWDD is how a neighborhood shares the cost of keeping the water flowing.

60–80 yrs Age of many private systems
~$95/yr Average for a quarter acre*
3 Elected neighbor trustees
$1,500 SRP rebate toward formation
The Basics

What is an IWDD?

An Irrigation Water Delivery District (IWDD) is a Maricopa County special taxing district made up of the property owners in a flood irrigated neighborhood. It collects a small annual amount with your property taxes and uses it for one job: maintaining and repairing the neighborhood's private irrigation system.

SRP delivers water to the delivery gate at the high point of your neighborhood. From that gate on, every pipe, gate, and ditch is private. Each owner is responsible for the valve on their own lot, and the shared lines between the gate and the homes belong to the neighborhood together.

An IWDD is formed through Maricopa County, not SRP, and it's run by three volunteer trustees elected from the neighborhood. It is not an HOA: it has no say over your house or yard. It only keeps the water moving.

Inspecting a neighborhood flood irrigation pipeline and gate in Arizona
Why It Matters Now

The "pass the hat" era is ending.

When these systems were built, there was no construction standard, and many of them are now 60, 70, even 80 years old. At the 2026 NCPHA Heat & Water Symposium, SRP's Stephen Peterson said SRP is seeing a huge spike in private system failures.

The old fix was one or two neighbors going door to door collecting money. That's getting harder. One North Central Phoenix resident at the 2026 Heat & Water Symposium described fixing one leak only to uncover the next, wrangling neighbors to chip in a hundred or two every couple of months, and finally starting a GoFundMe to keep the system running. Some owners who don't use the water don't think the shared line is their problem at all (and they couldn't be more wrong).

And the bills can be big. A break in a shared line under the street can require a bond and a licensed plumber, and repairs can run into the tens of thousands of dollars. Without a reserve, a single break can leave a whole neighborhood dry for weeks.

Flood irrigation valves on a private neighborhood irrigation system
What's the point of a district?

The benefits of forming an IWDD:

Money

Funds are ready when it breaks

The district builds a reserve in an account with the Maricopa County Treasury, so repairs get paid for right away instead of waiting on donations.

Fairness

Everyone pays their share

The cost is split evenly by acreage across every property in the district, including owners who stopped irrigating (but still benefit from the trees and grass in the neighbors' yards who do).

Convenience

No chasing neighbors

It's collected with your property taxes. Nobody has to knock on doors or track who has paid.

Value

Protects property values

Flood irrigated homes are becoming more valuable. A well-maintained, funded system protects that value for every owner.

Community

Keeps neighbors neighborly

It takes money out of neighbor-to-neighbor arguments, and the annual meeting gives everyone a reason to get together.

The Cost

About $7 or $8 a month, on average.

Costs vary by district, but SRP says the average it sees is about $95 a year for a quarter-acre property. That works out to roughly $7 or $8 a month to protect the system your yard, trees, and home value depend on.

The amount is calculated per acre. If a one-acre property pays $100, a half-acre property pays $50. Every year, the trustees submit a budget to Maricopa County, and if the current amount is working, the district can simply keep it.

This is separate from your regular SRP irrigation bill, which is a modest annual charge based on lot size. In districts like Rancho Solano, the SRP fee is also collected with property taxes, so nobody misses a delivery because a neighbor forgot to pay.

What Flood Irrigation Costs
"If we were to break that down monthly, we're talking about $7 or $8 a month to protect your irrigation system."
Stephen Peterson, Field Service Liaison, SRP

*Average cited by SRP at the October 2026 NCPHA Heat & Water Symposium. Your district's actual cost depends on the condition of your system and the budget your trustees set.

Getting Started

How to form an IWDD, step by step.

The process is involved, but you don't do it alone. SRP has a team dedicated to walking neighborhoods through it with Maricopa County.

  1. Talk to your neighbors

    Find out who's interested and who's frustrated with the current system. A few committed neighbors willing to organize (and maybe serve as trustees) makes everything easier. (Not sure if your property qualifies for flood irrigation? Shoot me an email and we can look into it together!)

  2. Contact SRP

    Call (602) 236-3333 and ask for an IWDD specialist, or email iwdd@srpnet.com. Through its Assisted Irrigation Delivery District program, SRP usually starts with a neighborhood meeting to gauge interest and answer questions.

  3. Assess the system and set boundaries

    SRP reviews the condition of your existing system and helps you map the district's boundaries and the water system it will cover.

  4. Complete the county paperwork

    SRP helps prepare the impact statement, request for resolution, and petition to Maricopa County. Maricopa County requires the petition to be signed by a majority of the owners of acreage within the proposed district. SRP's $1,500 rebate helps cover formation fees.

  5. County approval

    The Maricopa County Board of Supervisors reviews and approves the district. SRP attends the hearings and serves as your liaison.

  6. Elect trustees and set the budget

    Three homeowners serve as elected volunteer trustees for two-year terms. They submit the annual budget, identify problems, hire the contractor the district chooses, and make sure repairs happen so nobody misses a delivery.

SRP Will
  • Answer questions about your neighborhood system
  • Review the condition of your existing system
  • Help complete the applications and bylaws
  • Attend neighborhood meetings and county hearings
  • Help circulate petitions
  • Provide a $1,500 rebate toward formation fees
SRP Won't
  • Give tax or legal advice
  • Recommend contractors or get repair bids
  • Make repairs
  • Set your district's budget
  • Act as leverage for the district

Need a contractor? See the contractors I trust →

A Real Example · North Central Phoenix

Rancho Solano: "One less thing to worry about."

Rancho Solano, in North Central Phoenix, put its own irrigation district in place when the neighborhood was platted. At the symposium, resident Scott Mardian explained what that looks like day to day.

The SRP water fee is collected annually with property taxes, so deliveries never stop because someone forgot to pay. The district can build a reserve sized to the condition of its lines. And because the district keeps everyone's contact information, it does more than fix pipes: an annual potluck meeting plus three more neighborhood parties a year.

Compare that with neighborhoods that have no district, where the same few people end up organizing, collecting, and paying for every repair.

North Central Phoenix Guide

Scott Mardian on the Rancho Solano Irrigation District (4 min)

Hear It From SRP

Watch SRP explain IWDDs.

Stephen Peterson, Field Service Liaison with SRP, at the October 2026 NCPHA Heat & Water Symposium.

Loring Kort: life without a district →  ·  All symposium videos →

Frequently Asked Questions

IWDD questions, answered.

An IWDD is a Maricopa County special taxing district made up of the property owners in a flood irrigated neighborhood. It collects a small annual amount through property taxes and uses it to maintain and repair the neighborhood's private irrigation system: the pipes, gates, and ditches that carry water from the SRP delivery gate to each home. It is formed through Maricopa County, not through SRP, and it is run by three elected volunteer trustees who live in the district.
It varies by district. At the 2026 NCPHA Heat & Water Symposium, SRP said the average it sees is about $95 a year for a quarter-acre property, or roughly $7 to $8 a month. The cost is calculated per acre, so a half-acre lot pays twice what a quarter-acre lot pays. Each district submits a budget to Maricopa County every year, and the trustees can keep the amount the same if it is working.
No. SRP delivers water to the delivery gate at the high point of your neighborhood. From that gate on, the pipes, gates, and ditches are private and belong to the property owners they serve. Each owner is responsible for the valve on their own lot, and the shared lines that run between the gate and the homes are a shared neighborhood responsibility. An IWDD is the formal way to fund that shared responsibility.
Start by contacting SRP at (602) 236-3333 (ask for an IWDD specialist) or iwdd@srpnet.com. SRP's Assisted Irrigation Delivery District program will hold a neighborhood meeting, review the condition of your system, help set boundaries, complete the Maricopa County paperwork (impact statement, request for resolution, and petition), and walk you through approval by the Board of Supervisors. Maricopa County requires the petition to be signed by a majority of the owners of acreage within the proposed district. SRP also offers a $1,500 rebate to help with formation costs.
No. An IWDD only handles the neighborhood irrigation system. It has no say over your house, your yard design, paint colors, or anything else an HOA might regulate. It is a county special taxing district with a single job: keeping the shared irrigation lines working so every property gets its water.
SRP helps neighborhoods form and run a district, but it does not provide tax or legal advice, recommend or hire contractors, get repair bids, make repairs, set the district's budget, or act as leverage for the district. Those decisions belong to the district's trustees.

This page is general and educational, not legal or tax advice. Program details, costs, and county requirements can change. Confirm current details with SRP and Maricopa County before starting.

Keep Reading

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Buying, Selling, or Just Got Water?

Know what's behind the gate.

Whether a neighborhood has a district (and how healthy its system is) can matter as much as the house itself. If you're buying or selling a flood irrigated home, I'll help you find out where the water comes from, who maintains the lines, and what it costs before it becomes a surprise. Want the full checklist first? Grab my free Buyer's Guide.

Get the Free Buyer's Guide Work With Camille