Wairewa / Lake Forsyth plan change to be operative

Environment Canterbury announced today that Plan Change 6 to the Canterbury Land & Water Regional Plan, covering the Wairewa / Lake Forsyth catchment, would be made operative on 1 February 2017.

The Plan Change addresses both water quality and water quantity issues in the catchment. Environment Canterbury Councillor Peter Skelton said the main focus is on improving the health of Te Roto o Wairewa / Lake Forsyth by reducing the amount of phosphorus-rich sediment entering the lake.

“Phosphorus is a significant factor in the frequent cyanobacteria blooms that limit use of the lake for recreation and customary food gathering, and can pose a health risk.”

The Plan Change is part of a wider action plan to achieve improvements in the lake and rivers.

“There are environmental flow and allocation limits for the Ōkana, Ōkuti and Takiritawai rivers and their tributaries,” Professor Skelton said. “Works in or near these rivers and their tributaries in the valley floor to reduce bank erosion are supported, provided they comply with the requirements of a river bank erosion plan and do not reduce carrying capacity.

“There are also rules to allow for the construction of a sediment basin/wetland at the head of the lake, in-lake investigations, opening and closing the lake, water quality limits and targets for the lake and rivers, and requiring all stock to be kept out of waterways on the valley floor.”

Rules prohibiting stock from using and disturbing the beds, banks and riparian margins of rivers and the lake are designed to limit new phosphorus sediment being released to the lake.

“The stock exclusion rules apply from 1 January 2020,” Professor Skelton said. “They permit access to the riparian margin in some circumstances – where there is existing fencing, and to allow access for sheep when a consent is granted. There is no dairy farming in the catchment.”

The Plan Change recognises the cultural significance of Te Roto o Wairewa / Lake Forsyth to Ngāi Tahu and support its restoration.

Environment Canterbury accepted the recommendations of Independent Hearing Commissioners on proposed Plan Change 6 in August this year. No appeals were received. For more information, go to www.ecan.govt.nz/lwrp-pc6.

Background – Plan Change 6

Te Roto o Wairewa/ Lake Forsyth is a nationally and regionally significant wetland area. It provides lake-margin and swamp habitats for waterfowl (including the crested grebe) and a variety of salt and freshwater marsh plants and invertebrate species.

The lake and its tributaries provide habitats for a variety of fish species including eel/tuna, whitebait/inanga, flounder/pātiki, banded kōkopu, and common and upland bullies. The Ōkuti River is a spawning site for the lamprey/ kanakana. Perch and brown trout can also be found in the lake.

Te Roto o Wairewa/Lake Forsyth is a tribal taonga (treasure) for Kāti Irakehu and Kāti Makō. It is a source of mahinga kai (traditional food gathering) and famous for its eel / tuna which provide sustenance for mana whenua.

The 5.6 square kilometre shallow coastal lake is less than 20 metres above sea level and drains to the sea through a gravel barrier.

The growth of Kaitorete Spit has enclosed the lake, which was previously a shallow estuary. Deforestation of the catchment has accelerated the natural process of erosion, and subsequent loss of naturally rich phosphorus soils into the lake. Degraded water quality leads to summer blooms and cloudy water. The catchment is also prone to flooding.

The Banks Peninsula Zone Committee recognises the work of the Wairewa Rūnanga in seeking solutions to poor water quality in the lake, and reversing the decline of eel/tuna. It identified Te Roto o Wairewa / Lake Forsyth as one of its flagship biodiversity projects.

A community-driven plan for the catchment was started in 2012 and led to the development of the Zone Committee’s Zone Implementation Programme. The aim of the programme is to improve the lake’s water quality and mahinga kai and contact recreation values, and to manage water quantity in the catchment’s rivers.

Plan Change 6 represents the regulatory part of the Zone Committee’s programme.

Background – Land & Water Regional Plan

Plan Change 6 mainly focuses on reducing sediment and phosphorus losses in the flatter valley floor where most of the current sediment load to the lake comes from. The region-wide rules in the Canterbury Land & Water Regional Plan continue to cover most activities in the catchment. In particular, the region-wide nutrient management rules apply in the Wairewa / Lake Forsyth catchment.

The Land & Water Regional Plan will become fully operative on 1 February 2017. It sets the framework to implement community aspirations for water through the Canterbury Water Management Strategy, a community led, collaborative approach to improve water outcomes throughout the region.

The Land & Water Regional Plan operates at two levels – a region-wide section and 10 sub- regional sections. The policies and rules in the sub-regional sections can apply instead of, or in addition to, policies and rules in the region-wide section. The sub-regional sections implement the region-wide objectives in the plan in the most appropriate way for the catchment.

For more information on the Land & Water Regional Plan, go to www.ecan.govt.nz/lwrp