General
% of Christchurch population reticulated
(The remainder in rural areas have septic tanks and other on-site systems or a weekly nightsoil collection) | 99.9% |
| Number of households currently serviced by CWTP (as at February 2009) | 146,442 (approx) |
Length of time wastewater takes from kitchen sink to CWTP
(Amount of time varies from an hour to almost a day depending on distance from CWTP) | Max 24 hours |
| Average life of pipes | at least 90 years |
| Sewer system replacement cost | $1,225 million |
| % wastewater volume domestic | 86% |
| % wastewater volume commercial/industrial | 14% |
Reticulation
| Length of public pipe reticulation system | 1,626km |
| Longest single stretch of pipe (from furthest point to CWTP) | 20km |
| Smallest diameter pipe used | 150mm |
| Largest diameter pipe used | 1.8m |
| Length of large diameter trunk sewers | 13km |
| Length of pressure pipes | 150km |
| Number of manholes | 25,900 |
| Number of flush tanks | 1,630 |
Pumping
| Number of pumping stations | 120 |
| Number of pumps | 239 |
| Number of backup generators | 13 |
| Number of odour control sites | 33 |
| Number of lines leading from terminal pumping stations to CWTP | 5 |
| Total capacity of terminal pumping stations to CWTP | 6,610 l/s (litres per second) |
Treatment plant
Main treatment plant at Bromley providing: - screening
- pre-aeration and grit removal
- primary sedimentation
|
Liquids to: - trickling filter
- secondary sedimentation
- oxidation ponds
- Ocean Outfall
| Solids to: - digesters
- holding tanks
- belt press
- reuse in farm/forest
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