Whetstone Dwid, AZ
Lead detected, under the action levels
Latest 90th-percentile lead: 0.69 ppb (monitoring period 2022-2024). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. Lead was measured in sampled homes but the 90th percentile is under both action levels. EPA's health goal for lead is zero, so test your own tap if your home was built before 1986 or anyone in it is pregnant or a young child.
Who runs the water here
Whetstone Dwid serves about 940 people through 370 service connections, which makes it a small system under EPA's size classes. It is under mixed public and private ownership and draws groundwater, in Cochise County, Arizona. EPA system ID: AZ0402038; phone on file: 520-456-2125. Ask them for your address in their service line inventory - every system had to publish one by Oct 2024.
Whetstone Dwid's lead record
That is down 1.31 ppb from 2 ppb in the period ending 2021. The highest 90th-percentile result EPA holds for Whetstone Dwid is 2 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2024 | 0.69 ppb |
| 2021 | 2 ppb |
| 2018 | 1.9 ppb |
Against other Arizona systems
Of the 730 Arizona systems with a lead result, the median latest reading is 0 ppb; 9 are over 15 ppb right now and 58 have gone over at some point. Whetstone Dwid's 0.69 ppb sits at the 72nd percentile in Arizona and the 46th nationally (higher means more lead).
Other water systems in Cochise County
49 other systems share Cochise County; 15 of them have a higher latest lead result than Whetstone Dwid. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Bella Vista City Water System | 20,045 | 0 (not detected) |
| Douglas City Of | 16,656 | 0 (not detected) |
| Us Army Fort Huachuca | 15,603 | 0 (not detected) |
| Pueblo Del Sol Water Company | 12,804 | 0 (not detected) |
| Arizona Water Co - Sierra Vista | 9,233 | 0 (not detected) |
| Arizona Water Co - Bisbee | 8,590 | 0 (not detected) |
| Benson, City Of Water System | 5,355 | 0 (not detected) |
| City Of Willcox | 3,236 | 0 (not detected) |
| St David Dwid | 2,192 | 0 (not detected) |
| Bella Vista Water South | 2,178 | 0 (not detected) |
Next steps for Huachuca City, AZ
Test your own tap with a certified lab first-draw sample; Huachuca City, AZ may offer free or low-cost kits through the utility. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Whetstone Dwid whether it covers that cost before hiring anyone - many utilities now do.
These figures describe homes the utility sampled, not your tap. Only your service line record or a test of your own water answers the question for your house. Why sampled homes are the worst-case ones is in the guide to reading the number. The action level is dropping - the 10 ppb rule from 2027.