DDW-2025-001750

195 North 1950 West • Salt Lake City, UT
Mailing Address: P.O. Box 144830 • Salt Lake City, UT 84114-4830
Telephone [phone] • Fax [phone] • T.D.D. [phone]
www.deq.utah.gov
Printed on 100% recycled paper
State of Utah

SPENCER J. COX
Governor

DEIDRE HENDERSON
Lieutenant Governor
Department of
Environmental Quality

Kimberly D. Shelley
Executive Director

DIVISION OF DRINKING WATER
Nathan Lunstad, Ph.D., P.E.
Director

February 4, 2025

Shawn Douglas
Riverdale City Water System
4600 Weber River Drive
Ogden, UT 84405

Subject: Decreased Disinfection Byproduct Monitoring for Riverdale City Water System
UTAH29015

Dear Shawn Douglas:

The Utah Division of Drinking Water has changed the disinfection byproduct (DBP) sampling
requirements for Riverdale City Water System because the system's annual averages for Total
Trhialomethanes (TTHMs) and Total Haloacetic Acids (HAA5) in 2024 were below 40 ug/L and 30 ug/L,
respectively [R309-210-10(6)].

DBP Monitoring Requirements
The water system is now required to collect two (2) DBP sample(s) per year. Each sample must be a dual
sample set of total trihalomethanes (TTHMs) and haloacetic acids (HAA5). The next DBP samples must be
collected during the July 1 - September 30, 2025, monitoring period.

Questions
You may access an updated version of your water system’s monitoring schedule at waterlink.utah.gov by
searching for your water system and then clicking “Water Monitoring.” If you have any questions, please
contact Luke Treutel at [phone] or [e-mail].

Page 2
Sincerely,
Mark Berger
Monitoring & Standards Section Manager

cc: Shawn Douglas, Riverdale City Water System, [e-mail]
Scott Braeden, Weber-Morgan Health Department, [e-mail]
Luke Treutel, Division or Drinking Water, [e-mail]