Lake Benmore weed spraying notice

8 April 2009

Recreational and other users of Lake Benmore are advised that the herbicides Aquathol K® and diquat, in gel form, will be used in the Ahuriri Delta and Neck of Lake Benmore for lakeweed (Lagarosiphon) control between Monday 20 April and Friday 15 May 2009, subject to weather and lake conditions. The application of Aquathol K® is by helicopter, and diquat will be applied from a boat.

The spray operations may involve the discharge of harmless tracer dye during and/or prior to the spray operations. The dye is used to mimic the discharge of herbicides in order to obtain information about the dilution and dispersion characteristics after it has been sprayed on the target weeds.

The key adverse effect of the use of the dye will be the temporary visual impact of the dye plume in the water. The dye is harmless, there will be no adverse effects on the aquatic ecology of the waterbody, and the dye will continue to be diluted until it is no longer visible.

As a precautionary measure only Land Information New Zealand advises users not to take drinking or irrigation water from the vicinity of the treatment site until 24 hours after treatment.

24 hours prior to the planned application dates, notices will be placed with Port FM and on Land Information New Zealand’s website: www.linz.govt.nz. Warning signs will be placed at authorised public boat ramp sites during treatment and will be taken down 24 hours later.

Further information is available from:

Landward Management Ltd
P.O. Box 5627
Dunedin
Freephone 0508 244 746
Email: graeme@landward.co.nz.

The treatment works on Lake Benmore are a joint venture between Meridian Energy Ltd and Land Information New Zealand.