waterbycounty

Water Cost & Safety Calculator

Estimate your annual water costs and see your county's EPA-based safety grade. Covers 0 US counties.

0

Counties covered

4

EPA data sources

Free

No account required

Select a state and county to see your water cost estimate and safety grade.

How Water Costs Are Calculated

1

Select Your County

Choose your state, then pick your county from 3,100+ locations.

2

Set Household Size

Adjust for your number of people and your current filter setup.

3

See Your Estimate

Get your annual cost and EPA-derived safety grade instantly.

Your household water bill is driven by two factors: how much water you use and what your local utility charges per gallon. The national average residential rate is approximately $0.0068 per gallon (EPA/AWWA 2023), though rates range from below $0.003 in low-cost rural systems to above $0.015 in some high-infrastructure urban utilities.

EPA's WaterSense program estimates typical household consumption at 75 gallons per person per day — a useful baseline for budgeting even if your actual usage differs. Filter costs range from nothing (if you rely entirely on your municipal system) to $200–$450 per year for under-sink reverse osmosis or whole-house systems.

The safety grade is derived from two independent EPA datasets: SDWIS (compliance violations over a 5-year lookback) and ATTAINS (watershed impairment under the Clean Water Act §303(d)). A county with zero violations and mostly healthy waterways earns an A. Persistent violations or widespread watershed impairment push the grade down. The grade reflects the data available as of the most recent EPA reporting cycle — it is not a real-time reading.

Frequently Asked Questions

How is the annual water cost estimated?
We use the national average residential water rate of $0.0068 per gallon (EPA/AWWA 2023) multiplied by your household's estimated daily consumption (75 gallons per person per day, per EPA WaterSense). Filter costs are added based on typical annual replacement costs. Actual bills vary by utility, usage tier, and local infrastructure fees.
How is the water safety grade calculated?
The safety grade combines EPA SDWIS drinking water violation data (5-year lookback) with EPA ATTAINS watershed impairment data. An A grade means low violations and mostly healthy watersheds. An F means high violation counts or severely impaired waterways. Grade A = score ≥ 90 + ≤10% impaired; B = score ≥ 75 + ≤30% impaired; C = score ≥ 60; D = score ≥ 40; F = below 40.
Should I use a water filter if my county has an A grade?
Not necessarily. An A grade means your water system has an excellent compliance record with EPA drinking water standards. However, household plumbing (especially older lead pipes) can affect water quality after it leaves the treatment plant. If you have concerns about your specific home, a mail-in test kit provides the most accurate picture.
What does an EPA health violation mean?
A health-based violation occurs when a public water system exceeds the Maximum Contaminant Level (MCL) for a regulated substance, fails a required treatment technique, or misses a testing requirement. Systems are required to notify customers and take corrective action. Not all violations affect short-term health — some reflect monitoring failures rather than contamination events.
What is the difference between SDWIS and ATTAINS data?
EPA SDWIS (Safe Drinking Water Information System) tracks compliance at public water systems — the infrastructure that treats and distributes tap water. EPA ATTAINS (Assessment, Total Maximum Daily Loads, Tracking & Implementation System) tracks the health of rivers, lakes, and streams under the Clean Water Act — the ambient waterways that feed into reservoirs and aquifers. Both matter: SDWIS reflects treatment compliance; ATTAINS reflects source water quality.