Background on OWASA: OWASA is a community owned utility governed by 9 member Board of Directors appointed by elected Boards OWASA began operating in

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1 Background on OWASA: OWASA is a community owned utility governed by 9 member Board of Directors appointed by elected Boards OWASA began operating in Prior to this time, water and wastewater were separately owned and operated by UNC and the Towns 1

2 Our priority is to partner with the community to make the system more resilient. 2

3 The event occurred over a 34 hour period. 3

4 About OWASA s water system: 1 Water Treatment Plant capable of treating 20 million gallons per day; the community uses on average 7 million gallons per day 380 miles of water pipe 6 water storage tanks capable of storing 8 million gallons of water total 3 system interconnections to: Town of Hillsborough, City of Durham, and Chatham County increases system resiliency 4

5 What happened? Drinking water gets pumped out 4 different pipes leaving the Water Treatment Plant The pipe on the left was the one that broke During the break, we didn t know which of the 3 pipes, or which combination of the 3 may have broken. 5

6 What happened? The exact location of the break was hard to identify quickly. The volume of water flowing out of the break was too large for our staff to safely walk up to (in order to investigate the break) Other factors such as the depth of the break at 14 feet deep, and the pipe's location within a tight network of multiple pipes also made it difficult to identify quickly. We had to turn off valves and stop water flow at many different sections of the pipes in order to locate the break 6

7 What happened? We mobilized a repair team We activated interconnections with neighboring utilities and increased production at our Water Treatment Plant We activated the Emergency Operations Center with partners We communicated regularly with the public After stopping the leak, we de watered the site 7

8 Repairing the pipe: After we stopped the leak, Moffat Pipe contractors worked safely around the clock to make repairs and kept 1 lane open at most times on Jones Ferry Road 8

9 Locating the broken pipe: The red arrow shows the pipe that broke 9

10 The pipe that broke: A 16 inch cast iron pipe approximately 77 years old About 3% of our water pipes are made out of cast iron, and about 2% of our water pipes are 77 years or older. The American Water Works Association reports the average estimated service life for cast iron pipes at large water utilities in the South is 110 years old. See the report here: How does OWASA prioritize pipe repairs/upgrades? Our water main prioritization program prioritizes pipes to be upgraded and replaced based on industry assessment factors such as age, history of repairs and breaks, soil conditions, criticality of customers served, and pipe material. Our current five year Capital Improvements Program includes about $33 million dedicated to replacing 16 miles of water main pipes (about 4% of the distribution system). See the Capital Improvements Program here: fy19 23 web.pdf In January 2018, we shared a report on water main breaks and strategies we use to reduce main breaks. See the report here: 10

11 or_web.pdf#page=27 We use hydraulic models, prioritization models, and geographic information systems to inform our decision making. An average of 1.7 miles per year of new or replacement water mains have been installed over the past 10 years. 10

12 The team worked around the clock to make the repair. 11

13 This is the new pipe being installed. 12

14 To ensure continued water safety: Because system pressure dropped, we issued a boil water advisory, in case contaminants had entered the system We did system wide sampling: 43 samples from throughout the community. Once the samples are collected, the test takes 24+ hours to complete. All 43 samples taken throughout our service area passed. We immediately lifted the boil water advisory. 13

15 To ensure continued water safety: As an additional precaution, we did a second round of sampling and testing the following day. Again, all samples passed. 14

16 Working with community partners: Orange County Emergency Operations Center we worked with the Towns of Chapel Hill, Carrboro, UNC and UNC Hospitals throughout the event This was critically important and we are very grateful for their help 15

17 Joint Information Center All of the community partner s public information officers convened at the OWASA office to coordinate messaging to the public. Goal: provide accurate, timely information, and be responsive to questions and concerns 16

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21 We are working with a consultant who will seek answers to why the pipe broke, and why did it take 8 hours to isolate? Expect results in one month or so. We will provide a full report to public; count on us to be open and transparent. 20

22 Our priority is to make the system more resilient: Renewing and replacing aging infrastructure is critically important for OWASA as it is for utility systems throughout the country. OWASA has an active Asset Management program: about 50 cents of every dollar of OWASA revenue is invested in renewing and replacing our infrastructure. Since 2003, we ve used a water system prioritization model to help guide decisions about replacement work: to make the right investment, in the right places, at the right time. Over last 10 years, our pipe replacement has averaged about 1.7 miles per year. Our Board has supported investing about $33 million during the next 5 years to replace about 16 miles of pipe. The pipe that failed was not in our five year replacement plan. Models don t predict when a pipe will break, but they do provide valuable information about the likelihood and consequences of failure. We ve selected a consultant to replace our current model with the latest tool. It is our expectation that new model will do a better job guiding our investment decisions. We aim to have this running in about 1 year. We use valves in the system to stop the loss of water during water main breaks. We initiated a valve maintenance program in 2012 with the goal to exercise all 12,000 valves in our system every 5 years. With recent events, we will evaluate the effectiveness of our program and make needed improvements. 21

23 Our goal is to meet with community members and partners in the coming weeks and months, to invite community input and participation in decision making on local water and wastewater priorities. We aim to understand better unique customer needs and develop solutions together for increased resiliency. 21

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