What’s Really in the Water: Seagoville, Crandall and Combine Compared
A side by side look at the latest Consumer Confidence Reports for all three communities.
By Staff Reports • Shop in Seagoville • August 31, 2026
Seagoville, Crandall and Combine all receive treated surface water. Yet each city’s path to the tap looks a little different.
The newest Consumer Confidence Reports bring good news. Disinfectant levels, byproducts and lead results all stayed within federal limits.
Still, a few differences stand out. Crandall reported a small trace of arsenic, well under the legal limit.
Combine has not yet posted a 2025 report. Its newest report online still covers 2024.
Seagoville’s new report also raises a question about its listed water sources. That discrepancy is explained further down.
Seagoville
Lead: Not Detected
Chloramine average of 1.84 ppm
Crandall
Arsenic: 1 ppb
About 10% of the federal limit
Combine
Latest Report: 2024
2025 data not yet posted
Seagoville: Lead Not Detected at the 90th Percentile
Seagoville’s 2025 Water Quality Report covers testing from January through December 2025.
Chloramines control microbes in the water supply. They form when chlorine combines with ammonia, and they tend to last longer in pipes than free chlorine.
Chloramine average
1.84 ppm
Limit: 4 ppm
HAA5
4.05 ppb
Limit: 60 ppb
TTHMs
16 ppb
Limit: 80 ppb
Lead, 90th percentile
Not Detected
Action level: 15 ppb
Neither disinfection byproduct was reported as a violation.
Lead and Copper
Seagoville collected tap samples from 30 sites in 2025.
The 90th percentile lead result came back as not detected. Individual readings ranged from nondetectable to 1.07 ppb.
None of the 30 sites went over the 15 ppb lead action level.
Copper’s 90th percentile reading was 0.219 ppm, far below the 1.3 ppm action level.
Arsenic does not appear in Seagoville’s table of detected substances. That means it was not reported as detected, not that testing proved a level of exactly zero.
The report lists no violations for any substance in its results table.
Seagoville’s Source Water List Raises a Question
Seagoville’s report lists four water sources:
- Elm Fork of the Trinity River
- Lake Ray Hubbard
- Lake Tawakoni
- Bachman Lake
But that description does not fully match Dallas Water Utilities, the wholesale supplier for Seagoville’s treated water.
Dallas’s 2025 report names seven surface water sources instead:
- Elm Fork of the Trinity River
- Lake Ray Roberts
- Lake Lewisville
- Lake Grapevine
- Lake Ray Hubbard
- Lake Tawakoni
- Lake Fork
Dallas also lists Bachman as a treatment plant. It is not named as a current raw water reservoir source.
So Seagoville’s mention of Bachman Lake as a source does not match the wholesale provider’s current list. This is not a water quality problem, but it is something the city should clarify.
Crandall: Arsenic Detected, Far Below the Federal Limit
Crandall’s 2025 report identifies its drinking water as purchased surface water.
The main supply comes through the North Texas Municipal Water District and its Wylie treatment facilities. Crandall also has an emergency connection with College Mound Water Supply Corporation.
The Wylie system mainly treats water tied to Lake Lavon before it reaches member cities.
Chloramine average
1.72 mg/L
Limit: 4 mg/L
HAA5 (highest LRAA)
20 ppb
Limit: 60 ppb
TTHMs
39 ppb
Limit: 80 ppb
Crandall’s byproduct numbers ran higher than Seagoville’s. Both still stayed well under the federal limits.
Arsenic at 1 Part Per Billion
Crandall’s source water testing found arsenic at 1 part per billion.
The federal limit is 10 ppb. That means Crandall’s reading sat at about 10% of the legal limit.
The report marked this result as no violation.
Arsenic occurs naturally in rock and soil. It can also enter water through industrial or farm runoff.
A detectable trace should not be confused with an unsafe level. Crandall’s reading stayed well under the standard.
Lead and Copper Results
Crandall’s lead and copper table covers the 2023 through 2025 sampling period.
Lead, 90th percentile
1.67 ppb
Action level: 15 ppb
Copper, 90th percentile
0.876 ppm
Action level: 1.3 ppm
No sampling sites went over either action level.
Two Compliance Violations Reported
Crandall’s report also discloses two violations tied to the revised Lead and Copper Rule.
Both ran from October 17, 2024 through July 3, 2025.
One involved the initial lead service line inventory. The other involved initial lead service line reporting.
These are paperwork and reporting requirements. They are not findings that Crandall’s water exceeded the lead action level.
The report states there were no additional required health effects violation notices.
Combine: Latest Posted Report Covers 2024
Combine is the hardest of the three communities to compare directly.
Combine Water Supply Corporation’s newest report posted online is still the 2024 Consumer Confidence Report, issued in 2025.
That makes a true 2025 to 2025 comparison impossible using what is currently posted.
Combine’s report says the corporation purchases water from Seagoville, which gets its water from Dallas Water Utilities.
Total chlorine average
2.06 ppm
Limit: 4 ppm
HAA5
9 ppb
Limit: 60 ppb
TTHMs
17 ppb
Limit: 80 ppb
No violations were reported for these measurements.
Arsenic does not appear among the detected substances in Combine’s report.
Combine’s Most Recent Lead Testing
The lead and copper numbers in Combine’s 2024 report actually come from sampling done August 25, 2023.
Lead, 90th percentile
1.85 ppb
Action level: 15 ppb
Copper, 90th percentile
0.225 ppm
Action level: 1.3 ppm
No sites went over either action level.
Combine also reported its initial service line inventory to the Texas Commission on Environmental Quality in March 2025. At that time, the inventory showed no known lead service lines.
What the Numbers Show
None of the three systems showed water routinely above federal limits for the items reviewed here.
| Measurement | Seagoville | Crandall | Combine* |
|---|---|---|---|
| Disinfectant residual | 1.84 ppm chloramines | 1.72 mg/L chloramine | 2.06 ppm total chlorine |
| HAA5 | 4.05 ppb | 20 ppb | 9 ppb |
| HAA5 limit | 60 ppb | 60 ppb | 60 ppb |
| TTHMs | 16 ppb | 39 ppb | 17 ppb |
| TTHM limit | 80 ppb | 80 ppb | 80 ppb |
| Lead, 90th percentile | Not detected | 1.67 ppb | 1.85 ppb |
| Lead action level | 15 ppb | 15 ppb | 15 ppb |
| Copper, 90th percentile | 0.219 ppm | 0.876 ppm | 0.225 ppm |
| Copper action level | 1.3 ppm | 1.3 ppm | 1.3 ppm |
| Arsenic | Not listed as detected | 1 ppb | Not listed as detected |
| Arsenic limit | 10 ppb | 10 ppb | 10 ppb |
*Combine figures come from its latest publicly posted report, covering 2024. Its lead and copper results are from 2023 sampling.
The Bigger Difference May Be Transparency
The numbers themselves are reassuring. Disinfectant residuals, byproducts and lead and copper results all stayed under their limits.
Still, these reports show why residents should read past a simple pass or fail statement.
Crandall had reporting problems around its lead service line inventory. Its actual lead testing still stayed under the action level.
Combine’s public report is a year behind Seagoville and Crandall. That makes an equal comparison harder.
And Seagoville’s new report describes its water sources differently than Dallas Water Utilities, its own wholesale supplier.
Consumer Confidence Reports should answer four questions:
- Where does the water come from
- What was found in testing
- How much was detected
- Did the system follow the rules meant to protect people
For Seagoville, Crandall and Combine, the newest reports mostly show numbers within federal requirements.
They also show that how current and complete the information is matters almost as much as the numbers themselves.
Sources
- Seagoville 2025 Water Quality Report
- Crandall 2025 Water Quality Report
- Combine Water Supply Corporation 2024 Consumer Confidence Report
- Dallas Water Utilities 2025 Water Quality Report
