Environment

2.4 Wastewater

Parawai

Maintaining public health and safety and having clean waterways is essential to the city’s environmental wellbeing

What we do

Sewage collection and disposal

Sewage treatment

Our wastewater activities contribute towards us beingTop

People-centred – A safe and reliable wastewater network provides protection against public health risks.

Eco-city – A safe and reliable wastewater network provides protection against environmental harm.

Dynamic central city – A safe, reliable and well maintained wastewater network will function effectively and not cause disruptions to inner city living and business activities.

Key projectsTop

During the year:

What it costsTop

Operating Expenditure ($000) Actual
2013
Budget
2013
Variance
2013
Actual
2012
2.4.1 Sewage Collection and Disposal Network1        
Expenditure 17,277 16,998 (279) 16,315
Revenue (1,892) (595) 1,297 (2,780)
Net Expenditure 15,385 16,403 1,018 13,535
2.4.2 Sewage Treatment2        
Expenditure 21,877 21,590 (287) 21,847
Revenue (378) (657) (279) (1,262)
Net Expenditure 21,499 20,933 (566) 20,585
Capital Expenditure ($000) Actual
2013
Budget
2013
Variance
2013
Actual
2012
2.4.1 Sewage Collection and Disposal Network3        
Expenditure 6,882 7,117 236 8,069
Unspent portion of budget to be carried forward N/A 831   N/A
  1. Under budget due to the recognition of unbudgeted vested asset income.
  2. Variance is due to the consolidation of the Porirua Waste Water Treatment Plant Joint Venture. This variance is partially offset by lower landfill costs as a result the de-watering process reducing the mass of sludge transferred to the landfill, and lower than budgeted depreciation costs.
  3. Under budget due to savings on the Central Terrace sewer renewal, delays to the Beach Street sewer renewal and savings from the UV treatment upgrade due to a change in approach in addressing the treatment of bypass flows.

How we performedTop

Our wastewater activities should protect public health and property without compromising the environment. We measure our effectiveness by monitoring freshwater quality, resident satisfaction with the wastewater network and response times for service requests.

To measure the standard of the wastewater service

Customer (%) satisfaction with wastewater services

Customer (%) satisfaction with wastewater services.

Source: Capacity Infrastructure Services Ltd

Response time to service requests (%) within one hour of notification

Result: 67% of requests were responded to within one hour of notification (target: 95%; 2011/12: 96%; 2010/11: 91%).

Transition issues with the new service provider are being addressed. Despite the non-compliance no complaints were received.

Source: Capacity Infrastructure Services Ltd

Residents (%) who agree wastewater services provide good value for money

Result: 79% (target: 75%; 2011/12: 70%; 2010/11: 71%).

Source: WCC Residents’ Monitoring Survey 2013

To measure the impact of wastewater on the environment

Freshwater sites (%) within acceptable faecal coliform counts

Freshwater sites (%) within acceptable faecal coliform counts.

Investigations are under-way to determine the reasons for the high faecal counts. There are seven sampling sites we are investigating. To date the sources have not been identified though at some sites they have been narrowed down to a particular area. One site at South Karori Road was due to a leaking sewer main which has now been fixed. Pollution investigations, including structural examinations and dye tests, are continuing.

Source: Capacity Infrastructure Services Ltd

Sewage network – resource consent compliance

Result: 100% compliance5 (target: compliance: 2011/12: 100%)

Source: Capacity Infrastructure Services Ltd

5This result is based on the last formal confirmation received from GWRC in October 2012. The final confirmation of compliance from GWRC will not be received until after publication of this report.