Irrigation meter cost: is a second water meter worth it?

A separate irrigation meter costs anywhere from $859 (Raleigh Water, a 3/4-inch split on a new application, FY2027) to $6,830 or more (Denver Water’s minimum irrigation-only system development charge inside Denver, from July 1, 2026), before the backflow assembly and the plumbing. Whether it pays for itself depends almost entirely on one question: does your utility bill sewer on all the water you use, or on a winter average? In Charlotte, where sewer is billed on metered use up to a cap, our worked example below pays back in roughly 9 to 15 years. In Denver, where sewer is set from winter use, the sewer savings are zero.

This article goes deeper on the second-meter decision. For meter sizes, meter hardware prices and how capacity fees scale with size, see our water meter installation cost guide.

What you pay to add an irrigation meter

Utilities price a second meter in one of two ways. A split (or split tap) branches the irrigation line off the existing domestic service ahead of the house meter, so no new tap on the main is needed. A dedicated irrigation service is a new connection to the main and is usually priced like one, capacity fee included. A separate meter for an ADU is priced the same way, and capacity fees that scale with size are why upsizing a home meter for fire sprinklers costs thousands. The split is almost always cheaper.

Published one-time charges for a residential irrigation meter or irrigation-only service. Backflow assembly, plumber and irrigation contractor are extra. Checked 2026-09-24.

Three details change these numbers in practice:

• Capacity fees. Charlotte Water’s revenue manual (July 2023 revision) says a split irrigation line pays an adjusted connection fee and no system development fee. It also says that when the irrigation meter comes with a backflow device and a smart irrigation controller, the system development fee is waived and the connection fee can be paid over 12 months. A dedicated Charlotte irrigation line pays the standard connection fee instead. Raleigh’s fee guide lists its water and sewer capital facility fees per tap by meter size and doesn’t say whether a split irrigation meter pays them, so ask before you budget.
• Area-based pricing. Denver Water prices irrigation-only service by the size of the licensed property or the annual volume to be taken, and says the charge won’t fall below the SDC for the tap size installed. Beyond the first 5,000 square feet, it adds $1.09 per square foot inside Denver (July 1, 2026 schedule).
• Meter hardware. Raleigh adds its meter charge to every new water service ($290 for 5/8-inch, $420 for 1-inch, FY2027). Denver Water sells a 3/4-inch meter for $275.

In Seattle, SPU’s development charges rule (effective January 1, 2026) exempts irrigation services from the wastewater system development charge but lists no such exemption from the water SDC, which is $6,900 for a 3/4-inch meter. Confirm with SPU before you budget.

The sewer question decides the payback

Most of the savings from a second meter come from sewer charges. Some utilities don’t bill sewer on water through an irrigation meter, since it never reaches the drain. But many already keep lawn water off the sewer bill by basing residential sewer on winter use. If yours does, a second meter saves little or nothing on sewer.

How four utilities bill residential sewer, and what that means for a second meter. Checked 2026-09-24.

Austin’s rule is the one people miss. With an irrigation meter, you trade a winter average for your real indoor use every month. For a household whose indoor use rises in summer (guests, laundry, a pool fill through the house meter), that can raise the wastewater bill.

Worked example: Charlotte, where the math works

The household below is hypothetical. The rates are Charlotte Water’s FY2027 residential rates, effective July 1, 2026: water tiers of $2.11 (first 4 Ccf), $2.73 (5–8), $6.30 (9–16) and $11.93 (over 16) per Ccf; sewer at $6.88 per Ccf up to 16 Ccf; irrigation meters billed from Tier 3 ($6.30, then $11.93 above 16 Ccf) with no sewer charge. One Ccf is 748 gallons. The revenue manual says irrigation meters are subject to availability and fixed fee charges each month but doesn’t list an irrigation-meter amount. Our assumption: the irrigation meter carries the residential water fixed fee ($6.75) and the 5/8-inch water availability fee ($1.53), $8.28 a month in all. Charlotte Water doesn’t publish this combination, so confirm the actual monthly charge before relying on the result.

Summer month: 6 Ccf indoors, 8 Ccf on the lawn.

• One meter, 14 Ccf: water = 4 × $2.11 + 4 × $2.73 + 6 × $6.30 = $57.16. Sewer = 14 × $6.88 = $96.32. Total $153.48.
• Two meters: house water = 4 × $2.11 + 2 × $2.73 = $13.90; house sewer = 6 × $6.88 = $41.28; irrigation = 8 × $6.30 = $50.40, plus $8.28 in fixed fees. Total $113.86.
• Savings: $39.62 that month.

Heavy month: 6 Ccf indoors, 14 Ccf on the lawn. One meter: water $117.48 plus sewer at the 16 Ccf cap, $110.08, for $227.56. Two meters: $55.18 for the house plus $88.20 and $8.28 for irrigation, $151.66. Savings: $75.90.

Winter month, no irrigation. The irrigation meter still costs $8.28, so the second meter loses $8.28.

Over a year with six watering months at 8 Ccf: 6 × $39.62 − 6 × $8.28 = $188.04 saved. Against the $2,868 split connection fee alone, that’s 15.3 years to break even ($2,868 ÷ $188.04). A heavier waterer, four months at 14 Ccf and two at 8 Ccf, saves 4 × $75.90 + 2 × $39.62 − 6 × $8.28 = $333.16 a year and breaks even in about 8.6 years. Both figures exclude the backflow assembly, smart controller, plumbing and annual testing, which push payback out further.

Backflow: the recurring cost

An irrigation system connected to drinking water needs a backflow assembly, and utilities that require one usually require an annual test. That test is a cost every year the meter exists.

• Raleigh Water requires irrigation backflow assemblies to be tested by a City of Raleigh certified tester under City Code 8-2154, with results submitted online. Metered systems that fall out of compliance can be disconnected, with a $50 fee each time service is restored (City of Raleigh). Raleigh also bills all irrigation-meter water at its Tier 3 rate (Raleigh utility bill FAQ).
• Charlotte Water requires annual testing of backflow prevention devices and charges a test notification fee, per its revenue manual. The backflow device is also a condition of the irrigation-meter pricing described above.
• OUC (Orlando) lists $590 to install a backflow device on a residential 5/8-inch or 1-inch service and a testing charge of $48, or $4 a month, for devices 4 inches or smaller (OUC water tariff, January 2026).
• Portland Water Bureau lists $299 for annual testing of privately owned assemblies under Oregon Health Authority rules (FY2026-27 rate ordinance).

Break-even, step by step

1. One-time cost = connection or split fee + any capacity fee + meter charge + backflow assembly + plumbing and controller.
2. Monthly savings in a watering month = (sewer rate × irrigation volume, up to any cap) + (house-meter tier rate − irrigation-meter rate) × irrigation volume − the second meter’s fixed charges.
3. Monthly cost in a dry month = the second meter’s fixed charges.
4. Annual net = watering-month savings − dry-month costs − annual backflow test.
5. Years to break even = one-time cost ÷ annual net. If annual net is zero or negative, it never pays back.

If your utility sets sewer from winter use, step 2’s sewer term is zero and the result is usually negative.

When a second meter makes sense anyway

• Your utility or local code requires a separate irrigation service for your property type.
• Your utility bills sewer on total use and you water heavily for much of the year.
• You want outdoor use, and outdoor leaks, visible on their own bill.
• You’re adding it at the right time. Raleigh charges $859 for a 3/4-inch split on a new application and $1,775 on an existing one; ask Raleigh Water which applies to you.

Related guides

• Water meter installation cost and water tap fees
• Sewer connection cost and tap fee vs impact fee
• City fee pages: Charlotte, Raleigh, Denver, El Paso, Austin, San Antonio
• Utility connection cost calculator

Frequently asked questions