by Veronica Harrod
Horizons regional council wants ratepayers to pay for an integrated management plan to reduce pollution to Lake
Horowhenua even though the project was one of several that received $1.27 million funding in 2014 - including $540,000
from the Environment Ministry's Freshwater Fund.
A report presented to Horizons strategy and policy committee on 13 November asks for funding to "scope and price" the
development of an integrated sediment and drainage management plan for the Arawhata Catchment that flows into Lake
Horowhenua claiming that, “the work is outside of the area that is administered by the Lake Trust on behalf of the
Beneficial Owners of the lake. This project is largely based on roadsides and private land."
But the Environment Ministry's website states the total funding package for the Lake Horowhenua Project was to complete
a range of projects including, "An integrated storm water management plan for the Arawhata sub-catchment to reduce
sediment loss from horticultural farms and the stormwater drainage network."
A February 2017 update on completed projects does not mention the integrated stormwater management plan.
The Horizons report says, "Once the scope and costings have been further developed, staff will bring an item to council
to consider if the work should proceed and how it would be funded."
The report states that monthly monitoring clearly shows that the Arawhata Stream is the largest contributor of sediment
and phosphorous load to the lake.
"A more recent study has confirmed the Arawhata is currently the major contributor of sediment to the lake. The study
was completed as part of the Te Mana o Te Wai project for Lake Horowhenua led by the Lake Trust was completed in
collaboartion with Massey University and National Institute of Water and Atmospheric Research Ltd (NIWA)."
For the last five years the Arawhata Stream catchment has been identified as the source of between 48 and 75 percent of
sediment, and the Mangaroa Stream catchment has been contributing between 20 percent and 45 percent.
"In addition the sediment accumulation rates have increased in recent times."
The report says the Arawhata Catchment has a mix of land use that, “ includes lifestyle blocks, dairy farming and
approximately 400 hectares of horticultural land use" but a 2015 Horizons report said the catchment, "services some 620
hectares of cropping and dairy farms to the south of Lake Horowhenua....that ultimately discharges into Lake
The boundaries of the Arawhata catchment include Arawhata Road, State Highway 1, Hokio Beach Road and Buller Road.