Case study 3.6

Asset management for public entities: Learning from local government examples.

Wellington City Council – Asset information is best kept up to date by working effectively with partners

Wellington City Council has a sound approach to data collection, working closely with its partners and contractors to identify asset age, physical description, condition, and performance.

For water services in the city, the Council works in partnership with Capacity Infrastructure Services Limited to collect data and ensure that its databases remain up to date. The approach to data collection includes:

  • incorporating new, renewed, and vested assets into the asset information system through as-built drawings passed through Capacity Infrastructure Services Limited as part of signing off capital works;
  • the Customer Event Manager communicating with contractors who verify asset information during their work, as well as updating records about maintenance and renewals as the work is done;
  • a structured rolling programme of condition assessments with 16km of critical drains inspected annually; and
  • manhole inspection forms to verify data against records each time an inspection chamber is opened.

As a result of these controls over its data, the Council can be clear about the reliability of its data. Knowing that data is reliable helps the Council to be clear about how reliable its planning is likely to be. This minimises the likelihood that a large and complex network of assets will throw up any nasty surprises throughout the year.

Wellington City Council’s asset criticality ratings

CriticalityDescription of drains
(2% of the network)
Where collapse is the most expensive and disruptive to repair:
  • pipes > 375mm diameter (excluding the interceptor); and
  • brick drains.
(8% of the network)
Where collapse will have high cost and social impact, includes:
  • earthenware and asbestos pipes under buildings;
  • drains under arterial roads, railways, and the airport;
  • rising mains; and
  • the old interceptor.
(8% of the network)
Where collapse will have medium cost and social impact, includes:
  • remainder of pipes under buildings;
  • the new interceptor;
  • wastewater drains > 225mm in diameter;
  • stream crossings; and
  • drains deeper than 5 metres.
Managed on an as-required basis.