River Spraying Schedule

Monday 9 October 2017

This page lists current river-based weed spraying operations in the Tasman District.

Current Operations - October

Please note that activities are weather dependent and can change at short notice. Contractors should notify you ahead of time if your property is affected by these works.

2017/18 River Management Spray Programme (October – April inclusive)

River to be SprayedReachesPurposeEstimated Timing


All – Waimea East Irrigation Dam – Waimea Cycle Bridge

Control of woody weeds on dry gravel areas within channel.



Belgrove to Brightwater

Control of pest vines growing on banks especially chocolate vine

12 October onwards

Lower Motueka

Pangatotara to Big Pokororo

Control of woody weeds on dry gravel areas within channel


Upper Motueka

Hinetai Ford to Glenrae

Control of woody weeds on dry gravel areas within channel



Waikoropupu River confluence to Upper Takaka township

Control of woody weeds on dry gravel areas within channel


Other Rivers – depending on progress of the above.



Council’s contractor will contact adjacent landowners prior to undertaking the work. All spraying is intended to be ground based, mostly with a gun sprayer rather than a boom. Herbicides to be used include glyphosate, metsulfuron-methyl and triclopyr-BEE.

Some cutting and pasting may also be undertaken for pest vines.

More Information

Please contact River & Coastal Engineer Giles Griffith if you have any questions on (03) 543 7244.

About the Operations

  • The above information is indicative only. Spraying operations are highly weather dependent and conditions can change rapidly requiring a flexible approach to timing and locations. Weed control is only undertaken between Monday and Friday and not on public holidays.
  • Our contractor is required to contact all landowners adjacent to any river areas being sprayed ahead of time.
  • Spraying within river channels can only be undertaken between November-April inclusive due to resource consent requirements.
  • Spraying or other chemical weed control in riparian areas can occur at any time of year, but will almost aways be undertaken only during the growing season.

Agrichemicals Used and Method of Operation:

Typical herbicides used are glyphosate (i.e. Roundup), metsulfuron (i.e. Escort) and Triclopyr BEE (i.e. Grazon) along with an organo-silicone penetrant.

These are governed by the resource consent Council holds for this activity. When using herbicides in riparian areas above the flood channel a wider range of chemicals may be used. A red dye is used to make it obvious areas have been sprayed, and signage is used where there is a chance of the public inadvertently entering the area.

Weed control can be by manual methods using a backpack sprayer or cutting and painting, or by motorised methods using a vehicle mounted pressure sprayer. Boom spraying is able to be undertaken and helicopter spraying can also be carried out from time to time.