Project Maitai Restoration Newsletter July-Dec 2014

25 Feb 2015

Dear Project Maitai/Mahitahi partners, stakeholders and interested parties. Project Maitai/Mahitahi is Nelson City Council’s name for a programme of work to improve the health of the Maitai River so that the community feel inspired to look after the river and it is safe to swim in and take kai from. Although the programme is focused on the Maitai River, it is actually a catchment programme including Brook and York Streams, Groom and Sharlands Creeks and other tributaries. The project is delivered in partnership with community group the Friends of the Maitai, with input from key stakeholders and interested parties.

Project Maitai/Mahitahi is a discrete programme of work that sits alongside other Council projects related to the Maitai/Mahitahi River. These include the Maitai shared pathway, freshwater aspects of the Nelson Plan review, the renewal of the Maitai water take resource consent, any potential flood mitigation works on the river, and on-going operations and maintenance work. The Cawthron Institute also has a programme of research work related to the Maitai/Mahitahi River, and are hosting 5 summer research students who all have projects related to the river. In addition, the Friends of the Maitai have their own projects and programmes that are independent of Council.

The programme of work for the 2014/15 year consists of the 10 projects listed below, plus programme management and communications. We are anticipating that the programme will run for 3 more years and that the projects will change over that time as some are completed and new priorities are identified. Work will begin in February to design the programme for the 2015/6 year and we will be asking for ideas and input about which projects might be a priority. General feedback is welcome at any time.

Brief update on each of the projects to end Dec 2014:

Community Projects: matched funding for community projects that will help meet the goal of Project Maitai/Mahitahi.

  • 3 grants agreed, with 3 more grant applications in the pipeline

Riverside Planting: planting native trees, shrubs and grasses on the river banks to cool the water and provide habitat for native species, and to act as a filter to reduce contaminants and other materials entering the river.

  • 5500 tree and grasses planted in July and August
  • A staged 10 year planting plan for the Maitai/Mahitahi/Maitahi catchment is currently being developed, including extension of the existing inanga spawning area upstream from Collingwood Street bridge.

Maitai Dam: improving the water quality from the Maitai Reservoir so that it doesn’t affect the river.

  • Changes have been made to dam operations so that very low oxygen water is no longer fed back into the river from the reservoir, and monitoring is planned to see if this makes the expected difference to water quality in the river.
  • A contract has been awarded to analyse the costs and benefits of sourcing more of our drinking water from the reservoir rather than the South Branch.
  • A long term solution is being discussed, and options include: aeration of the reservoir, and/or oxygenation of water before it is backfed into the river, and/or increased use of reservoir water for drinking water and potential impacts on the treatment plant

River Flows: changing flow rates from the Maitai Reservoir so they are more like natural river flows.

  • Cawthron Institute are updating a previous habitat study which will make recommendations about optimal flow rates for river species.
  • A resource consent application is being prepared to trial a small artificial ‘fresh’ from the reservoir. If this is successful, a regime of variable flows from the reservoir will be trialled, dependent on resource consent, weather conditions and base river flow rates.

Stream Biodiversity: helping native fish and healthy stream critters make the Maitai/Mahitahi their home.

  • Cawthron have assessed fish passage issues and made recommendations for solutions (report). Fish passage has been installed at the South Branch backfeed weir and work is underway to install fish passage up and over the dam spillway. We are aiming to fix the barriers before peak elver migration in February.
  • Design has been completed for a sign at the inanga spawning site upstream of Collingwood St Bridge to educate the public about inanga life cycle and the importance of spawning areas and fish passage.
  • Fish distribution maps for Nelson including Maitai/Mahitahi/Maitahi have been completed and will be available on the NCC website. This information will be used to programme improvements to fish habitat and fish passage

River Gravel and Maitai Ford Investigations: understanding how best to manage gravel movement in the river, without causing negative environmental impacts, or increasing flood risk

  • NIWA has been contracted to provide a gravel management strategy report for the river, including advice and recommendations
  • Large boulders blocking fish passage at Almond Tree Flats ford have been removed, and follow-up monitoring is planned to see if fish can move past the ford. Plans are being developed put in fish passage at the Waahi Taakaro ford
  • Options for the Almond Tree Flats and Waahi Taakaro Golf Course ford sites are under discussion with user groups and will be further informed by the gravel management strategy work. Options under discussion include removal, or modification, and/or changes to on-going maintenance and operations.
  • In the meantime a chain and signage has been put up to prevent inappropriate use of the ford by vehicles and campers.

E. coli Chasing: finding out where the bacteria in the swimming holes downstream of Riverside Pool are coming from, and fixing any sewerage leaks we find.

  • Dye testing has identified three likely sources for E.coli contamination of the river. These have been fixed and re-tested.
  • Recent monitoring of the lower reaches for E. Coli showed encouraging results but we won’t be able to say it is safe to swim at Collingwood St Bridge until we have a run of consistently low readings. We are still seeing periodic spikes of elevated readings, particularly after rainfall, and human faecal markers were still present 10m down from Collingwood St Bridge and in Saltwater Creek.
  •  Investigations are continuing to identify contamination sources

Forestry: working with stakeholders to reduce the potential impact of forestry operations on the river.

  • The forestry project team has met twice to discuss possible actions and identify opportunities for implementing good practice

Stock Fencing: making sure cattle can’t get into the river

  • Groom Creek (and the small creek beside golf course) have been fenced off from stock.
  • Plans have been made to fence out cattle from the top of York Stream.

Brook Culvert: making the Brook Stream as fish friendly as possible, while still reducing flood risk

  • Tonkin and Taylor have been appointed as consultants for the Brook Stream channel modelling. York stream channel modelling will also be done concurrently.

If you have feedback, or for more information on how to get involved and upcoming events please go to the Friends of the Maitai website at www.friendsofthemaitai.org.nz, the Friends of the Maitai facebook page, or the Nelson City Council website at www.nelson.govt.nz and search on Project Maitai. Alternatively you could email the friends of the Maitai at info@friendsofthemaitai.org.nz  or jo.martin@ncc.govt.nz .

Kind regards

Jo Martin
Environmental Programmes Officer
Manager Maitai Programme

Nelson City Council / Te Kaunihera o Whakatû
03 545 8728