Ohakune Wastewater Treatment Plant Upgrade
This project in 2007 was completed as the Major subcontractor to Heb Smithbridge, MAP Projects ( formerly Bema) provided Project Management and all plant and labour for river outlet and protection works, earthworks, retaining walls, concrete structures, filter media and gravel access roads.
- ” Physical works undertaken in a native bush, with a water course through site, and difficult access. Implementation, management and monitoring under detailed site specific Erosion & Sediment control plan and detailed construction methodology resulted in considerably less native bush removal than initially anticipated. Site clearance, 1,500m³ topsoil to stockpile, 4,500m³ cut and borrow to fill, 1,000m³ cut and undercut to waste and 300m³ topsoil respread to the batter. MAP placed over 3000m3 of drainage media in varying across the wetlands ponds.
- Installed over 500 metres of 250 and 300mm plastic pipes to grades varying from level to 1 in 100. Trench depths varied from 1.3 metres to almost three metre and were often below the water table
- ” UV Disinfection Chamber, 6m long, 3m wide and 3.6m deep chamber to accommodate the UV disinfection unit was constructed below the water table. Pours were complete in three lifts with dewatering in place until the third lift. No through ties were used in the bottom lifts to provide a waterproof structure. Pond Outlet Structure, These complex structures were required to facilitate three way flow and included wiers and a number of pipe penetrations. Given the 2.4m overall height and narrow chambers these were poured insitu in two lifts
- Constructed 120 metre long gabion wall at Ohakune and 4 metre high by 10m long double wall at Raetihi. Constructed 300m2 of Reno Mattresses on the Ohakune Project.
- Supplied, placed and compacted 900m2 of subbase for access roads, other quarry products placed and compacted on site included over 3000m3 of media filter