A Journey From Age Based Renewals Towards Optimised Long Term Condition Based Renewals

Hastings District Council (HDC) has historically planned its wastewater renewals programme using an age based renewal methodology. Recent assessments of the asset age profiles, predicted backlogs and maintenance records highlighted discrepancies between the forecast age based renewals and actual asset condition and performance. The existing planning methodology predictions did not match the reality we were experiencing. 

This paper discusses HDC’s journey away from a purely age based renewals planning methodology towards a more robust condition and risk based renewals planning strategy enabling a responsible approach to “sweating” the asset. 

The paper will discuss the steps taken in this journey towards a more advanced asset management approach including: 

• Step 1: Age based asset data system analysis. This identified a substantial backlog that was in significant contrast to actual asset performance/condition/collapses/maintenance costs. 
• Step 2: Collection of age based data condition. This involved range of investigation techniques including CCTV, laser and sonar profiling, core sampling and destructive testing. 
• Step 3: Base asset life assessment. This resulted in an increase in the remaining life of three major asset types based on material. 
• Step 4: Development of a condition and risk based renewals planning framework. Three key asset groups, based on criticality and risk, were identified and three very different intervention strategies were developed for each asset group. 
• Step 5: Renewals programme development for the 2015 Long Term Plan (LTP) and 30 year infrastructure strategy. 
• Step 6: Identification and implementation of improvement activities. 

The adoption of this renewals planning strategy allows HDC to efficiently and responsibly “sweat” their waste water assets. It has smoothed funding requirements, enabled long term renewals forecasting in a manner that focuses risk, and ensures maximum value is achieved from the assets and renewal budgets.