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1.0 CIMCITY COMMISSION INFORMATION MEMORANDUM ADMINISTRATIVE BRIEF FROM MARTHA TASKER March 21, 2022 Increase in Water Main Breaks in 2021 The original water distribution system was constructed prior to 1900. The construction that took place in the late 1800's through the 1960's was with cast iron pipe (CIP). In the 1970's and 1980's, ductile iron pipe (DIP) with cement lining was installed, and from the 1990's polyvinyl chloride (PVC) pipe has been installed. The water distribution system consists of approximately 333 miles of water main. Today, the Salina water distribution system is 195 miles CIP (60%), 75 miles DIP (22%), and 63 miles PVC (19%). The following graph shows the number of water main breaks per year from 2000 through 2021. For this time period, the average is 115 water main breaks per year, and the number of water main breaks in 2021 was 164. 200 180 160 m m > 140 d CL x 120 m d c 100 m a 80 d a E 60 z z S:9 20 Salina Mainbreaks 2000-2021 2000200120022003200420052006200720082009201020112012201320142015201620172018201920202021 Year Approximately $20 million of water main replacements have been financed, contracted for and construction is nearly complete. From the year 2022 and beyond, $2.0 million per year in water main replacements will be funded through revenues from the water rates. The long-term goal is to keep water rates reasonable for our customers, while meeting the long-term replacement needs of the water distribution system to ensure a reliable and high quality water supply to our customers. Sub -zero temperatures in the winter months and extreme hot and dry conditions in the summer months can cause water main breaks. Whether it is hot or cold, the ground changes or shifts (contracts or expands). When it is cold, the ground tends to contract, and when it warms up, it expands. The water mains are not flexible and due to that, the main breaks. Water usage during summer months is typically 8-9 million gallons per day (mgd) and winter usage is typically 3-4 mgd. This variation in usage causes fluctuation in velocities and water pressure through the water mains, increasing the stress in the water mains and adding to the possibility of the water mains breaking. Water main breaks are typically identified as one of the following: Blowout: A portion of the wall of the pipe is blown out diameter / 6 -inch x 6 -inch opening) Split: A split (longitudinal crack) occurs in the wall of the foot in length) Circle Break: A break around the circumference of the (typically results in two pipe sections being off -set) (ranges from 1 -inch to 1 -foot pipe (ranges from 1 -foot to 10 - pipe, sheering the pipe in two Blowouts and splits typically occur as a result of pressure changes and a weak pipe. Circle breaks typically occur as a result of the ground shifting and putting stress on the water main to a point where it breaks. During the year the water main breaks tend to be split equally for the above identified types of breaks. The following tables compares Salina's number of water main breaks with neighboring communities for the years of 2018 and 2021. The color code of green represents a decrease in water main breaks and red represents an increase of water main breaks between years 2018 and 2021. city Main Breaks in 2018 Miles of Water Main Main Breaks per 100 miles— ilesTo eka Topeka 847 890 95 Has 53 128 41 Salina 110 333 33 Wichita 579 2,400 24 Newton 28 140 20 Manhattan 54 298 18 Hutchinson 35 307 11 Main Miles of Main city Breaks Water Breaks in 2021 Main per 100 miles Topeka 538 890 Has 32 120 353 Salina 164 Wichita 1019 2530 Newton 24 160 Manhattan 67 301 Hutchinson 82 307 On average, the Utilities Department cost to repair a water main break is approximately $3,500. In 2021, with 164 main breaks, the estimated cost is $574,000 for repairs. The following map indicates the water main breaks were spread throughout the city where CIP is installed. WATER MAIN BREAK LOCATIONS ;_.._. 2021 _L - F _-�W MHWY- ..� ' to rl —4if 6 as I — Q: I _ • IL eW-+�l!- ---=° j E'XaWord'St .s �, ,•y p L g p �... ° 0 0.38 =hNks `..�ir.. l.._. 0 2021 Watu Main freaks