Southgate Water Company, WA
Lead reported as not detected
Latest 90th-percentile lead: reported as 0 (not detected) (monitoring period 2021-2023). The federal action level is 15 ppb today and drops to 10 ppb in Nov 2027; EPA's health goal is 0. The latest 90th-percentile result was reported as 0 (not detected at the lab's limit). That says the sampled homes were low, not that your home has no lead service line. Check your utility's service line inventory for your address.
Who runs the water here
Southgate Water Company serves about 175 people through 83 service connections, which makes it a very small system under EPA's size classes. It is privately owned and draws groundwater, in Benton County, Washington. EPA system ID: WA5356344. Ask the utility on your bill for your address in their service line inventory.
Every lead result on file
Against the period ending 2020 (1 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Southgate Water Company is 2.7 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2023 | 0 (not detected) |
| 2020 | 1 ppb |
| 2017 | 2.7 ppb |
Where this result ranks
Of the 2,218 Washington systems with a lead result, the median latest reading is 1 ppb; 18 are over 15 ppb right now and 62 have gone over at some point. Southgate Water Company's reported as 0 (not detected) sits at the 20th percentile in Washington and the 14th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Other water systems in Benton County
42 other systems share Benton County; 14 of them have a higher latest lead result than Southgate Water Company. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| Kennewick City Of | 118,164 | 0 (not detected) |
| Richland City Of | 106,499 | 2.4 ppb |
| West Richland City Of | 21,231 | 0 (not detected) |
| Prosser City Of | 8,030 | 0 (not detected) |
| Benton City Water | 5,626 | 0 (not detected) |
| Badger Mountain Irrigation District | 2,331 | 2.8 ppb |
| Summit View Water System | 1,869 | 0 (not detected) |
| Bc Water Co | 1,262 | 0 (not detected) |
| Community Sewer And Water District | 1,200 | 0 (not detected) |
| Oasis Water Corporation | 556 | 0 (not detected) |
What to do in your house
Look up your address in Southgate Water Company's service line inventory. If it says lead, galvanized or unknown, test your tap. If your own line is lead, replacing the private side runs about $1,200-$12,300 (EPA average about $4,700). Ask Southgate Water Company 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. What a 90th-percentile result does and does not tell you: how to read a lead result. A zero today does not rule out a jump later - the rules are tightening in 2027.