1. Galt WWTP Clarifier Renewal Program
Richard Pinder
Region of Waterloo, Senior Project Engineer
Thomas Uda
GHD, Asset Management Consultant
CNAM 2014 Conference
Toronto, Ontario
May 20-23, 2014

2. Background Information
Region of Waterloo has 13 WWTPs, consisting of 20 primary and 36 secondary clarifiers
Pilot a clarifier renewal strategy at the Galt WWTP for five primary and six secondary clarifiers

3. Objectives
Make informed decisions related to maintenance and capital programming activities
Justification of yearly expenditures on maintenance and renewal
Develop a program we could use

4. Galt WWTP Clarifiers Primary Clarifiers Secondary Clarifiers
Plant A (4 x 18.3m)
Plant B (1 x 25m)
Secondary Clarifiers
Plant A (4 x 22.86m)
Plant B (2 x 31m)

5. Project Steps
Understanding the current state of maintenance planning activities
Improving the Current State
Prioritization of Maintenance (Risk Profiles)
Lifecycle Costing (three options considered)
Recommendation and Overall Cost Summary

6. Understanding the Current State of Maintenance
Understand the existing failure modes of the clarifiers
Gear drive typically fails from bearing wear and improper lubrication
Other assets are structural elements that fail due to overall wear, rusting, or corrosion
Use failure modes to identify gaps in clarifier maintenance activities

7. Improving the Current State: Maintenance Program
Development of strategies based on criticality to reduce risks and prevent unexpected failures
Condition-based
Time-based
Run-to-failure
Key step: Input from operators

9. Improving the Current State: Maintenance Program
Gear drive failure is a main source of reactive maintenance
Increase frequency for changing oil and checking gear drive for wear
Inexpensive and less critical components follow a run-to-failure strategy
Scum heater and level transmitter

10. Improving the Current State: Maintenance Program
Current asset hierarchy
Recommended asset hierarchy

11. Prioritizing Maintenance: Developing Risk Profiles
Risk depends on probability and consequence of failure
Condition assessment = physical mortality

12. Prioritizing Maintenance: Developing Risk Profiles
Plant B clarifiers are the highest priority (lack of redundancy compared to Plant A)

13. The Lowest Cost Approach: Lifecycle Costing
The goal is to perform the right maintenance and renewal activities at the right time
Three approaches to maintenance and renewal are considered
50 year lifecycle

14. The Lowest Cost Approach: Lifecycle Costing
Option 1: Minimal preventive maintenance
Option 2: PM Program with scheduled asset replacement
Option 3: Similar to Option 2, but refurbishments are performed to extend the effective life of the asset

15. The Lowest Cost Approach: Lifecycle Costing
Capturing Consequence Costs
Repair or replacement cost
Cleanup
Extra labour
Contingency Plans
Option 1: Highest Consequence Costs
Option 2 and 3: Benefit from timing the renewal of assets in groups

16. Option 3 (PM Program with refurbishment) results in lowest lifecycle cost

17. The Lowest Cost Approach: Lifecycle Costing
Example of Yearly Costs

18. The Lowest Cost Approach: Lifecycle Costing
Costs (run-to-failure vs scheduled renewal)

19. The Lowest Cost Approach: Lifecycle Costing
12 Year Outlook

20. Conclusions
Operator involvement is key to developing and implementing a renewal plan
Renewal Plan assists in focusing resources on critical and high risk assets
Risk can be quantified in dollar values by estimating the cost of the consequence of failure

21. Conclusions
The Region’s current maintenance strategies were in line with Option 3 (preventive maintenance and refurbishment strategy).
Renewal plan justifies this approach compared to other maintenance approaches
Prioritization of assets was established
(PC#5, SC#5, and SC#7)

22. Next Steps
The renewal plan is an ongoing process; refurbishment and renewal intervals are to be updated
The recommendations from this project contribute to the Region’s overall Capital Improvement Plan
Similar strategies are planned to be implemented for clarifiers at other Region WWTPs

23. Questions? Contact Us: Richard Pinder Region of Waterloo
Thomas Uda
GHD, Asset Management Consultant