Rio Wsc, TX
Lead reported as not detected
Latest 90th-percentile lead: reported as 0 (not detected) (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. 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.
About Rio Wsc
Rio Wsc serves about 6,939 people through 2,313 service connections, which makes it a medium-sized system under EPA's size classes. It is owned by a local government (city, town, county or district) and draws surface water, in Starr County, Texas. EPA system ID: TX2140016; phone on file: 956-487-2085. Call that number and ask whether your address has a lead, galvanized or unknown service line.
Every lead result on file
Against the period ending 2021 (0 ppb) the latest result is about the same. The highest 90th-percentile result EPA holds for Rio Wsc is 1.21 ppb across 3 monitoring periods, none of them over 15 ppb.
| Period ending | 90th-percentile lead |
|---|---|
| 2024 | 0 (not detected) |
| 2021 | 0 (not detected) |
| 2017 | 1.21 ppb |
Where this result ranks
Of the 4,447 Texas systems with a lead result, the median latest reading is 0.28 ppb; 15 are over 15 ppb right now and 202 have gone over at some point. Rio Wsc's reported as 0 (not detected) sits at the 44th percentile in Texas and the 36th nationally (higher means more lead). Systems reporting 0 tie at the bottom, so the rank mostly reflects size among them.
Neighbouring systems
8 other systems share Starr County; 1 of them has a higher latest lead result than Rio Wsc. If you are unsure which one supplies your house, the name on your water bill decides it.
| System | People | Latest lead |
|---|---|---|
| City Of Roma | 19,464 | 0 (not detected) |
| City Of Rio Grande City | 18,912 | 0 (not detected) |
| City Of La Grulla | 11,250 | 0 (not detected) |
| Union Wsc | 5,793 | 0 (not detected) |
| Falcon Rural Wsc | 3,600 | 1.48 ppb |
| El Tanque Wsc | 3,000 | 0 (not detected) |
| El Sauz Wsc | 2,223 | 0 (not detected) |
| Ibwc Falcon Village | 48 | 0 (not detected) |
What to do in your house
Look up your address in Rio Wsc'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 Rio Wsc 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.