Water System Design - The Role of O&M Staff

1. Water System Design -The Role of O&M Staff Cheryl Capron Seattle Public Utilities

2. Why Include Operators and Maintenance Staff? Incorporating their knowledge makes a project more successful. • Better integration of project with existing system • Reduces the amount of work re-done by O&M staff once project is closed • Potential reduction in CIP & O&M costs

3. What Kind of O&M Staff? • System Knowledge • Detail-Oriented • Ones who notice subtle changes or discrepancies in data • Inquisitive • Ones who ask why • Analytical & Persistent • Ones who figure out why Bill Nye

4. What Should They Know About?

5. Infrastructure Trouble Spots • That’s pretty soggy ground for a flex coupling… • We need another isolation valve; that one’s awfully close to the excavation zone. • That 80-year-old valve hung up last week at 30% open...

7. Infrastructure Trouble Spots • It’s 80 psi down there and most of those gate valves leak – we should replace them when we reline…..

9. O&M Practices & History • Why it’s done • How it’s done • Why this way? • Staffing levels • How long it takes • Constraints

11. Instrumentation & Control Needs • Identify desired level of I&C and automation • Identify what’s appropriate for the operator’s level of accountability Ed Harris as Gene Kranz in Apollo 13

12. System Water Quality • Knows normal and seasonal variations Good, bad or normal?

13. System Water Quality • Can identify probable impacts of events or changes in operation Four impacts that can result from high velocities are...

14. Their Perspective

15. How Will It Work? • Will the design allow the project to function as required? • How will the project change the way my system operates? Is that acceptable?

16. What Will It Take to Make It Work? • To bring it on line • To operate it • To maintain it

17. What Happens With Pieces Out For O&M? • An automated pump station starts when pressure drops below 90 psi. The gauge needs to be replaced. It is isolated, causing the input to the PLC to drop out. Does the PLC • interpret the missing point as a valid reading <90 psi & start a pump? • flag the data as invalid and hold last valid status? • have a manual over-ride or bypass mode?

18. Worst-Case Scenario • What could go wrong? • How hard would it be to rectify? • How long will it take? • Is it even a big deal?

19. What Can O&M Staff Do For You?

20. Pre-Design • Functional Requirements Analysis • For the project • For system during construction • For start-up & commissioning • For O&M

21. Pre-Design • Draft shutdown & start-up plans • Draft a pressure zone or system operating plan for the construction period • Identify bypass needs & constraints imposed by the loss of the facility • Identify major system maintenance that should be done prior to NTP

22. Zone Base Map • Boundaries • Storage • Supply • Major Feeders • Shut Down Valves • Primary • Backup

23. Zone Map for Backup Inlet Shutdown • South end isolated, needs new relief point • South end PS has reduced service area, throttling capability on discharge needed

24. De-Watering • Identify blowoff points • Calculate volumes • If the whole thing sits for a month, can I disinfect & flush the required volume? • Requires either a short-term shutdown or a new isolation valve before the reservoir is demolished.

25. Why Do This During Pre-Design? • The answers to these questions will identify whether there are elements that need to be incorporated into the design. • Is a new isolation valve required? • Are air valves, blow-offs and sample points where they are needed? • Is a specific construction sequence required?

26. Challenges of Replacement Projects • Capacity reduction may require bypass • Connecting new to old may be difficult • Old valves leak or break easily • Disturbing old pipe or bedding may cause leaks • Long, large dead ends for extended periods • Flushing, disinfection, no sample points

27. Sequencing Multiple Shutdowns • Maintaining service & fire flows • How many blocks to the nearest hydrant? • How many streets in a row on temporary? • Diurnal & seasonal demand • What happens to your shutdown if you have to back up another valve?

28. Pre-Design • Draft O&M review checklists • Do this early and give them to the designers so they know what you’ll be looking for.

29. Design Review • Include O&M staff at all stages of review. • As design becomes more refined, their review becomes more specific & focused on how they will operate & maintain project. • If items are deleted, include O&M staff in the decision-making process. • Reduction in CIP $ frequently means increase in O&M. Make sure your staff can handle what you’re committing them to.

30. Start-up & Commissioning • Acceptance Testing (Not the manufacturer’s & contractor’s equipment testing & commissioning) • Does the project work with your whole system like it’s supposed to? • Documentation • Test results/findings • Operating procedures

31. Post-Implementation • Go back & talk to the O&M staff • What’s working well? • What’s been changed? Why? • What would they do differently next time?

32. Questions? cheryl.capron@seattle.gov