More than $9 million will be needed over the next 10 years to carry out soil conservation, flood protection and river management work considered essential in Environment Waikato’s Upper Waipa management zone.
The scope of the work and attendant costs have been outlined at a meeting of the Upper Waipa Liaison Sub-committee by Project Watershed staff.
Project Watershed is a two year programme aimed at developing a catchment-wide approach to river management and funding, based on six separate management zones.
The scale of the proposed soil conservation work is massive, but reflects the fact that no such works have been previously carried out by Environment Waikato within the Upper Waipa zone, which stretches from the upper reaches of the Waipa and its tributaries down to Otorohanga.
Environment Waikato staff have identified three priority areas for soil conservation work in the Upper Waipa Zone:
It is estimated that 7841 hectares is at risk of severe erosion within the Upper Waipa zone, with a further 23,216 hectares consider a moderate risk. Nearly 300 kilometres of stream bank is considered to be an existing or potential erosion problem.
Project Watershed proposals are for 300 ha of pole planting ($300,000), 1047 ha of block planting ($1,290,700) and 283 km of fencing within the hill country areas of the zone ($2,807,200), over a 10 year period.
Riparian protection proposals are for fencing 496 km of stream bank ($1,587,200), riparian planting of 347 km ($1,238,500) and providing alternative water supplies over 496 km ($248,000).
In addition, Project Watershed staff have identified flood protection opportunities in the Mangapu, Mangaokewa and Mangawhero, which could cost up to $2,500,000, but the local communities have indicated that they did not want to see this work carried out at this time.
River management initiatives expected to cost around $74,000 per year will see work carried out in the Waipa River and Waimahora, Mangapu, Mangawhero, Mangarapa and Mangaokewa Streams, mostly in the lower reaches.
Comprehensive river management works in the Waipa River for gravel management, river training and stabilisation and managing the Tunawaea landslip have an estimated capital cost of $1,400,000.
Project Watershed staff are currently carrying out an informal consultation programme to identify an acceptable level of work to be included in a draft management plan for the whole Waikato catchment that will be put out for formal consultation in June.
Environment Waikato chairman Neil Clarke says if local people have an early input then the draft plan is more likely to match their community’s expectations.