A separate irrigation meter is not automatically a money-saver for a Tampa Water customer. It adds a monthly base charge and removes the home’s sewer maximum. The comparison must include both changes—not just the outdoor gallons that would leave the household meter.

The City does not recommend one when the existing sewer maximum is below 10 ccf and/or the lawn and landscape area is below 10,000 square feet. A potable irrigation meter still uses potable-water consumption pricing; it is not a reclaimed-water connection. City meter guidance

First identify the benefit you already have

Tampa’s sewer-maximum explanation describes a residential wastewater allowance recalculated from consumption history. After the first year, the City uses a third-lowest-month method; established accounts are recalculated each January using up to 24 months. Homes with irrigation meters are excluded.

That existing allowance matters: do not estimate savings by multiplying every outdoor gallon by a sewer rate. Ask the utility to compare wastewater charges with the existing sewer maximum against charges based on indoor use after separation.

A seasonal comparison can reverse the answer

Use this LSL model with figures confirmed for your account:

Annual operating saving = annual wastewater-charge reduction − added meter base charges − any increase in water charges − added recurring upkeep.

Treat a reduction in water charges as a negative increase. Include differences caused by account configuration; do not assume the two water totals match without checking.

Here is a deliberately simplified example, not Tampa’s rates, a contractor quote or a household forecast. Assume:

  • $18 less wastewater cost in each month that benefits;
  • a $12 additional base charge every month;
  • no change in water charges or recurring upkeep; and
  • $720 in nonrefundable setup costs.

If all twelve months benefit, the result is 12 × $18 − 12 × $12 = $72 saved per year. Simple payback is $720 ÷ $72 = 10 years.

If only six months benefit, it becomes 6 × $18 − 12 × $12 = −$36: operating costs rise by $36 a year, before setup. There is no positive payback in that case.

This arithmetic deliberately isolates seasonality. It does not model financing, future rate changes or replacement work. A one-month saving is insufficient evidence for a purchase.

Get the missing numbers before agreeing to installation

The City’s installation guidance assigns application, deposit and installation fees, onsite connection and a backflow device to the customer. It also says base charges change on October 1. Obtain figures for the intended service date, not an old bill alone.

Ask Water Development Services at 813-274-7405 to identify the proposed meter charge and account treatment. Then obtain a separate private-work quote. Distinguish refundable deposits from nonrefundable costs: both affect initial cash needed, but only the latter belong in the simple payback numerator.

LSL compared the two City explanations on September 23, 2026 and reproduced the examples above. No private account, current dollar tariff, installation price or measured saving was verified.