District Headquarters
50 Elm St., Dedham, MA 02026
During Office Hours:
781-329-7090
After Hours Emergency:
781-326-1250
50 Elm St., Dedham, MA 02026
781-329-7090
781-326-1250
TTHMs are a group of disinfection byproducts that form when chlorine compounds, which are used to disinfect water, react with other naturally occurring chemicals in the water. They are colorless and will evaporate out into the air. There are four significant TTHM (chloroform, bromoform, bromodichloromethane, and dibromochloromethane) potentially found in disinfected drinking water and their combined concentration is referred to as total TTHM.
The Dedham-Westwood Water District solicited bids for a TTHM Reduction System in Spring 2022.
Construction for the system was completed in September 2023. Tank mixers, aerators, and vents are active at the District’s four water storage tanks.
We will continue to monitor the public drinking water supply for all regulated inorganic substances, synthetic organics, volatile organic compounds (VOCs), Total Coliform, e.coli bacteria, unregulated (secondary) substances, organic disinfection byproducts, radionuclides, as well as lead and copper. Our team is committed to providing clean, safe water. As stewards of this valuable resource, we take our job to protect public health and safety seriously. Our team of 30+ professionals work around the clock to provide reliable, cost-effective, high-quality water service that protects public health, promotes environmental stewardship, maintains customer confidence, and supports economic development and sustainability.
The standard for TTHMs is 80 PPB. Compliance is determined on a quarterly basis by averaging all samples collected at each location for the last 12 months, Running Annual Average (RAA).
| Sample Location |
Quarter 1 (January - March 2025) |
Quarter 2 (April - June 2025) |
Quarter 3 (July-September 2025) |
Quarter 4 (October - December 2025) |
OEL Q4 | LRAA | Dedham Medical Associates |
Date: January 4, 2025
PPB 31 |
Date: April 25, 2025
PPB 35 |
Date: July 3, 2025
PPB 56 |
Date: October 2, 2025
PPB 91 |
68 | 53 |
|---|---|---|---|---|---|---|
| Getty Gas Station |
Date: January 4, 2025
PPB 71 |
Date: April 25, 2025
PPB 79 |
Date: July 3, 2025
PPB 61 |
Date: October 2, 2025
PPB 71 |
71 | 71 |
| East Dedham Fire Station |
Date: January 4, 2025
PPB 8.9 |
Date: April 25, 2025
PPB 35 |
Date: July 3, 2025
PPB 30 |
Date: October 2, 2025
PPB 74 |
53 | 37 |
| Far Reach Pump Station |
Date: January 4, 2025
PPB 35 |
Date: April 25, 2025
PPB 33 |
Date: July 3, 2025
PPB 52 |
Date: October 2, 2025
PPB 34 |
38 | 39 |
| Maximum Contaminant Level (MCL) = 80 (PPB) | Was OEL exceeded? NO | Was MCL exceeded? NO | ||||