This chart lists all regulated detections in water sampled as part of SUB’s water quality program. If a known health-related contaminant is not listed, it was not detected. In 2025, your water met, and in many cases exceeded, all state and federal requirements.
(For a key to abbreviations and terminology used in this table and testing notes, see page 8)
| Water Test Inorganics |
Unit | Federal limit | Federal goal | Year tested | SUB’s system range detected | Year tested | RWD’s system range detected | In compliance? | Typical source(s) |
| Arsenic | ppb | 10 | 0 | 2025 | ND - 3.7 | 2021* | ND - 5.1 | Yes | Erosion of natural deposits |
| Barium | ppb | 2000 | 2000 | 2025 | ND - 3.3 | 2021* | ND - 3.8 | Yes | Erosion of natural deposits |
| Fluoride | ppm | 4 | 4 | 2025 | ND - 0.058 | 2021* | ND - 0.056 | Yes | Erosion of natural deposits |
| Nitrate | ppm | 10 | 10 | 2025 | 0.059 - 1.5 | 2025 | ND - 2.4 | Yes | Natural deposits, runoff from fertilizers, leaching from septic tanks, and sewage |
| Disinfectant | |||||||||
| Chlorine | ppm | MRDL = 4 | MRDLG = 4 | 2025 | 0.31 - 0.77 RAA = 0.59 |
2025 | 0.41 - 0.76 RAA = 0.56 |
Yes | Water additive used to control microbes |
| Disinfection byproducts | |||||||||
| Haloacetic Acids | ppb | 60 | 0 | 2025 | ND - 11 LRAA = 10 |
2025 | ND | Yes | Byproduct of drinking water disinfection |
| Total Trihalomethanes | ppb | 80 | 0 | 2025 | 1.8 - 23 LRAA = 18 |
2025 | ND - 4.0 | Yes | Byproduct of drinking water disinfection |
*The State allows water systems to monitor for some contaminants less than once per year because the concentrations of these contaminants do not change frequently.
A key to abbreviations and terminology in this document:
- AL or ACTION LEVELS: Concentration of a contaminant which, if exceeded, triggers treatment or
other requirements a water system must follow. - CONTAMINANT: Any physical, chemical, biological, or radiological substance or matter in water.
- Federal Limit or MAXIMUM CONTAMINANT LEVEL: The level of a contaminant in drinking water below
which there is no known or expected risk to health, as set by the Environmental Protection Agency (MCLGs allow for a margin of safety). - Federal Goal or MAXIMUM CONTAMINANT LEVEL GOAL: The highest level of a contaminant allowed in drinking water. MCLs are set by the Environmental Protection Agency to be as close to the MCLG as
feasible using the best available treatment technology. - HERBICIDE: Any chemical(s) used to control undesirable vegetation.
- LRAA or Locational Running Annual Average: The continual running average from each previous sample site.
- MRDL or Maximum Residual Disinfectant Level: The highest level of disinfectant allowed in drinking
water. There is convincing evidence that addition of a disinfectant is necessary for control of microbial
contaminants. - MRDLG or Maximum Residual Disinfectant Level Goal: The level of a drinking water disinfectant below
which there is no known or expected risk to health. - MRDLGs do not reflect the benefits of the use of disinfectants to control microbial contaminants.
- N/A: Not applicable.
- ND: Not detected.
- NSF or National Sanitation Foundation 61 Standard: Coatings are commonly used materials in potable water applications to protect storage tanks from corrosion. The NSF 61 standard certification of coating products ensures that this product will not impart harmful levels of contaminants into drinking water.
- NTU or NEPHELOMETRIC TURBIDITY UNITS: Units of measure for turbidity.
- pCi/L: Picocuries per liter (a measure of radioactivity)
- PESTICIDE: Generally, any substance or mixture of substances intended for preventing, destroying,
repelling, or mitigating any pest. - PPB or PARTS PER BILLION: One pound of contaminant per billion pounds of water.
- PPM or PARTS PER MILLION: One pound of contaminant per million pounds of water.
- PPT or PARTS PER TRILLION: One pound of contaminant per million pounds of water.
- RAA or Running Annual Average: Computed using monthly or quarterly results and is a value used for
compliance. - RWD: Rainbow Water District, a wholesale water provider.
- TT or TREATMENT TECHNIQUE: A required process intended to reduce the level of a contaminant in
drinking water. - TURBIDITY: A measure of the cloudiness of water caused by suspended particles.
- UNREGULATED CONTAMINANTS: Contaminants that don’t yet have a drinking water standard set by
Environmental Protection Agency (EPA). The purpose of monitoring these is to help EPA decide whether the contaminants should have a standard. - UCMR: Unregulated Contaminants Monitoring Rule
(see page 7)