Water Quality Report · Updated October 07, 2026
OTAY WATER DISTRICT
OTAY WATER DISTRICT delivers tap water graded B (78/100) by TapWaterSafety.org. The utility serves approximately 238,008 residents in SPRING VALLEY, California using surface water (purchased). The most significant water quality concerns are: Haloacetic acids (HAA5) significantly above health guideline; Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline. For questions, the utility can be reached at 619-670-2210.
Is SPRING VALLEY tap water safe to drink?
OTAY WATER DISTRICT delivers tap water that earns a grade of B (78/100) from TapWaterSafety.org — a good rating, with only minor concerns relative to health-based guidelines.
The utility serves 238,008 residents in SPRING VALLEY, drawing from surface water (purchased).
Public testing data identifies 12 contaminants in this water above EWG's health-based guidelines, including: Haloacetic acids (HAA5), Haloacetic acids (HAA9), Total trihalomethanes (TTHMs), Bromodichloromethane, Dibromochloromethane, Dibromoacetic acid, Dichloroacetic acid, Chloroform, Trichloroacetic acid, Bromoform, Chromium (hexavalent), Bromochloromethane. For most residents, a properly certified home filter at the kitchen tap is the most cost-effective way to reduce exposure to whatever's in your water. See our filter recommendations below, matched specifically to this utility's contaminant profile.
EPA compliance record
Official U.S. EPA records for OTAY WATER DISTRICT (system ID CA3710034) for the last 3 years. Checked 2026-10-07.
Source: U.S. EPA Enforcement and Compliance History Online (ECHO), from the Safe Drinking Water Information System. See EPA's full report.
Quick actions for SPRING VALLEY residents
Top concerns in this water
Based on the most recent EPA and EWG data, these are the most significant water quality issues for OTAY WATER DISTRICT.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 36.2 ppb, 362x above the EWG health guideline of 0.1 ppb.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 14.4 ppb, 240x above the EWG health guideline of 0.06 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 24.1 ppb, 161x above the EWG health guideline of 0.15 ppb.
Contact OTAY WATER DISTRICT
Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.
General Contact
Treatment Plant
Recommended water filters for SPRING VALLEY
Filters matched to the specific contaminants in this water supply.
Carbon filter certified for VOCs (NSF/ANSI 53)
$180-$599Activated carbon is effective for disinfection byproducts. Look for NSF/ANSI 53 VOC reduction.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
Score breakdown
This utility's overall score of 78/100 breaks down across five weighted components. Read the full methodology →
Contaminants detected — international standards comparison
Every contaminant detected, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal (the strictest US benchmark). Why we show multiple standards →
| Contaminant | Detected | EWG US health-based |
EPA US legal |
EU DWD Europe |
WHO global |
CA PHG strictest US |
Tested sample year |
Status |
|---|---|---|---|---|---|---|---|---|
| Haloacetic acids (HAA5) Disinfection byproduct |
36.2 ppb | 0.1 | 60.0 | 60 | — | — | — | 362× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
14.4 ppb | 0.06 | — | — | — | — | — | 240× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
24.1 ppb | 0.15 | 80.0 | 100 | — | — | — | 161× over |
| Bromodichloromethane Disinfection byproduct |
7.47 ppb | 0.06 | — | — | — | — | — | 124× over |
| Dibromochloromethane Disinfection byproduct |
7.63 ppb | 0.1 | — | — | — | — | — | 76× over |
| Dibromoacetic acid Disinfection byproduct |
2.08 ppb | 0.03 | — | — | — | — | — | 69× over |
| Dichloroacetic acid Disinfection byproduct |
4.75 ppb | 0.2 | — | — | — | — | — | 24× over |
| Chloroform Disinfection byproduct |
6.26 ppb | 0.4 | — | — | — | — | — | 16× over |
| Trichloroacetic acid Disinfection byproduct |
1.45 ppb | 0.1 | — | — | — | — | — | 15× over |
| Bromoform Disinfection byproduct |
2.78 ppb | 0.5 | — | — | — | — | — | 5.6× over |
| Chromium (hexavalent) Heavy metal |
0.0499 ppb | 0.02 | — | — | — | — | — | 2.5× over |
| Bromochloromethane Other |
0.0739 ppb | 0.06 | — | — | — | — | — | 1.2× over |
| Chlorate Disinfection byproduct |
178.4 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Molybdenum Other |
3.76 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Vanadium Other |
1.68 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
2.72 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Strontium Radiological |
0.842 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Lithium Other |
13.7 ppb | — | — | — | — | — | — | Below guideline |
All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.
Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines (4th ed.), California OEHHA PHGs, EWG Tap Water Database.
OTAY WATER DISTRICT service area
This water system serves 1 community in San Diego County, California. Click any city for its dedicated tap water quality page.
Find the right filter for SPRING VALLEY water
Browse filter categories by water-quality concern. Each option below is NSF-certified for the matched contaminant type.