An overview of the key findings from the ‘Source Catchments as Water Quality Treatment Assets Project’
C Wearing, J Cheesman, S Skull, G Ramachandran, K Henderson
Publication Date (Web): 14 July 2016

Water utilities undertake catchment management for a variety of reasons. Catchment management programs may be a regulatory requirement to complement conventional water treatment, or they may be voluntary. Some utilities consider them an investment that can provide non-traditional and often additional non-monetised environmental and social benefits. Regardless of the driver, water utilities need to understand how catchment management programs can be incorporated into an infrastructure investment decision-making process.

In an economically regulated environment where consumer affordability is paramount and where the regulator puts the burden of proof on the water provider to illustrate successful mitigation of water quality risk, there are two critical challenges:

  1. How can a sound business case be made for investment in catchment management as a water quality ‘treatment’ option, using best practice approaches in triple bottom line cost benefit evaluation?
  2. How can it be demonstrated, in the geographic context of the catchment under consideration, that mitigation measures can be successfully implemented and water quality improvement is achieved? 
With these two critical challenges in mind, WSAA and WRF have undertaken the Source Catchments As Water Quality Treatment Assets project on behalf of their members.

In particular, the project developed a Catchment Management Investment Standard (the Standard) to assist water utilities to build stronger business cases for catchment management as a viable alternative to more traditional, capital intensive investments. The Standard provides users with a summary of key steps and practices needed for a robust and evidence-based investment in source catchment management activities.

The Standard is supported by a number of tools including a benefit cost assessment tool and extensive database of the non-monetary benefits of catchment investments.
Its development was informed by a Rapid Stocktake. This encompassed a high-level assessment of key lessons from catchment management initiatives and programs in the United States and Australia including case studies of key catchment management issues.

The standard has 11 steps:

  1. Identify significant assets and set minimum and target levels of service (develop a Strategic Asset Management Plan);
  2. Clearly articulate the need (problem definition);
  3. Identify the funder (s) and stakeholder (s), develop a constituency and build partnerships;
  4. Agree on the level of evidence the investor wants to approve the investment;
  5. Assemble the evidence base (define and identify high value assets);
  6. Show community support and willingness to pay;
  7. Prepare an investment Logic Map;
  8. Identify strategic reponses;
  9. Do a first-pass filtering of the long list of strategic reponses and get investor sign-off on the short list;
  10. Prepare the compelling investment case;
  11. Monitor, evaluate, adapt. 

It is hoped the Standard will provide invaluable help to water utilities in Australia and the United States to make the case for catchment management for drinking water supply. We look forward to its widespread use and, of course, to its progressive improvement over time. 

Example of customer, planning, tactical and operational levels of service for water supply:


Reliability of safe water supply not to exceed an outage of more than 6 hours.


Water supply needs for current and 10-year future capacity of the township: this would be measured through performance metrics. For example, a minimum of 4ML/day based on projected usage for a peak summer day.


For a water aqueduct

  • Minimum hydraulic capacity 4ML/day for 99.8% of the time
  • Maximum duration of low flow not to exceed 6 hours.
  • Safe to operate and maintain.
  • Durability to be able to perform their required functions for at least their nominated design life.
  • Will not endanger the public or cause unnecessary disruption.
  • Minimise contamination risk.
  • Meet or better the water leakage loss target.


Secured from unauthorised access and tampering.

  • Maintained to remove debris and flow conveyance.
  • Performance condition greater than 3 requires intervention.
  • Safety assessed using HAZID process.
  • Outage for maintenance not to exceed 6 hours.
  • Leakage reported and rectified where practical.
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