Mangere Wastewater Treatment Plant
CEE 491 Sean Schultz Lampros Mitropoulos Scott Honjiyo Presentation Contents
Project overview Project use and benefits Technical issues and innovations Social problems and policy issues Project overview Location: Auckland, New Zealand
Plant was first opened in 1960 Oxidation pond system covers more than 500 hectares (app 1,236 acres)
Began upgrade construction in May of 1998
Opened on April 4, 2003 by Prime Minister
Run by Watercare Services limited (Public)
Price: $450 Million Project Usage
LandLand basebase water treatment system Upon final filtering and UV disinfection, the flow is transferred to Puketutu Island, where the channel feeds into the 17 hectare intertidal storage basin. Has the capacity to cater to Auckland’s growing capacity.
Provide significant environmental benefits to Manukau Harbor
Better quality effluent discharge Positive Impacts
Improves the Environment Provides bathing water quality to discharge into harbor 500 hectares of oxidations ponds and sludge lagoons returned to a natural harbor environments 13 km of coastline also improved Biggest coastal restoration effort in New Zealand
Odor Boundary established and upheld
Treatment cycle reduced from 21 days to 13 hours
Haven for thousands of migrating birds Bird roosts built for birds resting while tide covers their feeding grounds Technical Issues and Innovations
Transformed the old Mangere Wastewater Treatment Plant 5 year project, treatment processes have been replaced Plant reduces the treatment cycle for wastewater from 21days 13 hours Primary Treatment
■ Fine screens: From 19mm 3mm gaps between bars Extraction of inorganic material has increased from 1 5 tonnes/day
■ Pre aeration tanks
■ Primary sedimentation tanks 12 tanks (70x12m)
■ Upgraded Strengthening, re coating the tank surfaces
■ 2 products ( Sludge & wastewater)
■ Gravity thickening Secondary Treatment ■■ New process Biological Nutrient Removal (BNR)
■■ 9 Reactor/Clarifiers (D=77m)
■■ Capacity for 200,000 people/unit
■■ Reactor 4 aerobic & 4 anoxic compartments
■■ Clarifier 2 products (Activated Sludge & wastewater) ■■ Solid waste Dissolved air flotation (DAF) thickeners
■■ 7 Anaerobic sludge digesters (15 days)
■■ Dewatering plant (100 300 wet tonnestonnes/day)/day) ■■ Effluent from clarifier
■■ Filtration (10 massive filters) ■■ Particles > 15 m (=(=1515 1010 −6−6 m)
■■ UV disinfection plant largest in the world (10,000reduction in viruses) ■■ 12 parallel channels ■■ 7776 UV lamps
■■ Discharge (300,000m 22/day) ■■Treatment plant required to be fully operational during construction
■■Local Government Act –– Statement of Corporate Intent
■■Nine separate management plans
■■Resource Management Act –– Very strict conditions such as: ■■ 16 species in New Zealand. ■■ Huge nuisance factor. ■■ Monitoring and surveys required. ■■ Use of control sprays ––SectionSection 15 of Resource Management Act ■■ “Code of Practice for the Management of Agrichemicals” ■■Final Filtering and UV Disinfection.
■■Runs along main effluent channel.
■■Water, after upgrade, is of high enough quality for shellfish and even swimming. ■■ Treaty of Waitangi Claim.
■■ Maori People. Oruarangi Creek.