Waituna Lagoon Project

This page provides information on the Waituna Lagoon Project. It received Crown funding from the Fresh Start for Freshwater Clean-up Fund from 2012 to 2015 to address historical water quality issues.

Project details

Project cost

$1.6 million

Crown funding

$785,000

Location

Waituna Lagoon, Southland

Parties

Southland Regional Council, Dairy NZ, Department of Conservation, Federated Farmers, Fert Research, Southland District Council.

Iwi

Te Ao Marama Inc.

Project purpose

To restore the water quality of the Waituna Lagoon to a level sufficient to maintain a healthy seagrass dominated ecosystem.

Project timeframe 2012-2015

Background

Waituna lagoon is a large brackish coastal lagoon on the southern coast of the South Island. In its natural state the lagoon is macrophyte dominated and brownish in colour with a low pH. It is a system that has very high ecological habitat diversity and supports an intact seagrass community, internationally important birdlife, and large areas of relatively unmodified wetland and terrestrial vegetation. In addition, it is highly valued for its aesthetic appeal, its rich native biodiversity, duck shooting, fishing, boating, walking and scientific appeal.

Water quality in the lagoon and the creeks that flow into it are under stress from many years of land development upstream in the catchment. This land development has included drainage of wetland areas, the clearance of indigenous vegetation, changes in lagoon water levels and land use intensification. These factors pose the risk of the lagoon becoming eutrophic (murky water dominated by algal slime).

Funded interventions

The following interventions were funded to improve water quality issues:

  • riparian fencing and planting, and reconstruction of eroded stream banks to reduce the amount of sediment, nitrate and phosphorous entering the lagoon and wetlands
  • planned artificial lake opening to flush out pollutants
  • managed flooding of farmland.

Final project update – December 2015

By the end of the project in December 2015 the following had been achieved:

  • reconstruction of over 14km of stream banks
  • construction of two artificial wetlands.
  • an artificial opening of the lagoon to the sea to assess options for managing lagoon water quality.

Preparing a channel at the constructed wetland (Warnock Wetland)
(Photo: Environment Southland)

 

Planting in the pond at the new Warnock Wetland
(Photo: Environment Southland)

 

Planting day at Warnock Wetland
(Photo: Environment Southland)

Find out more

Waituna Lagoon [Environment Southland website]

Awarua Wetlands [Department of Conservation website]

Reviewed:
14/02/17