Public notices

Bathing water quality update

30 January 2010

Over the summer season Council regularly monitors the quality of the swimming water in a variety of locations.

The freshwater and marine bathing water quality results from all marine sites show very healthy water quality, whilst there have been some issues at a few freshwater sites.

Monitoring is based on the Microbiological Assessment Categories (MAC). MAC grades range from A, which has very low bug counts and never exceeds guideline levels through to D which has high bug counts and regularly exceeds the guidelines.

Water quality results for 2009/2010 are well within guideline limits this year with improvements in water quality at some sites. The Collingwood Street Bridge 2008/2009 grading was D (Very Poor).  Results from this summer’s monitoring have indicated an improvement in the lower Maitai water quality as a consequence of improvements to the Collingwood and Trafalgar Street drainage and sewerage systems.

The Collingwood Street Bridge monitoring site has breached guidelines once this year and there remains a temporary health warning issued last year advising people not to swim in this part of the river.

The Wakapuaka River at Hira Reserve and Paremata Flats Reserve 2008/2009 grading was D (Very poor). The Paremata Flats Reserve has breached guideline levels twice this year and there has been one breach at the Hira Reserve. A temporary health warning has been issued advising people not to swim in the river at Paremata Flats Reserve until further notice. A warning notice has also been put up at the Paremata Reserve swimming hole. The most likely source of this contamination is from feral animals and domestic stock within the catchment, although septic tanks could also be contributing. Residents in the areas have been briefed on the situation and encouraged to minimise stock access to the river and to maintain their septic tank systems.

What to avoid this summer

Contamination of river water can occur during or shortly after rainfall from storm water runoff. To minimise the risk of exposure to harmful bacteria it is best not to swim for the first 24 hours at least after rainfall that leads to any discolouration of the water.

Toxic Algae

Fresh water algae is more prominent in our streams and rivers over summer months and can grow rapidly forming blooms (mats), particularly during periods of stable warm weather and low flows. Some blue-green algal mats (thick dark brown mats) produce toxins under natural conditions that can be fatal to dogs and potentially harmful to humans, livestock and wildlife.

Monitoring of algae this summer shows very low presence, possibly a reflection of both the changeable weather and variable river flow.

River users, particularly those with dogs, or those taking water for livestock or human consumption, should avoid contact with any thick dark brown-black algal mats. If blue-green algal mats are widespread in a river you should presume that the water may be unsafe.

Council and Cawthron Institute staff regularly check recreational bathing sites for the presence of blue-green algae.

Download an information leaflet about toxic blue-green algae (PDF @ 2MB).

Partial closure of Dun Mountain walkway for logging

The private forest either side of the Dun Mountain walkway between Tantragee Saddle and Brook-Fringe track is now closed to all access until the forestry harvest is completed.  The closure will be in force between 6am to 6pm Monday to Friday inclusive, with the track being open outside these hours. It is critical that people stay out of the area during the closure as contractors are working directly above the track.

Hand application of cyanide paste

Maitai and Roding waterworks catchments

Nelson City Council will be laying cyanide from time to time with the Maitai and Roding waterworks catchments to control possums.

During periods of poisoning, warning signs will be in place in accordance to section 95A of the Hazardous Substances and New Organisms Act 1996.

 Do not dump greenwaste in reserves and parks

Permanent notice

Staff working for Nelmac, the company contracted to look after parks for Council, report ongoing problems with residents around parks dumping their greenwaste and garden rubbish over fences and onto public land. This causes Council to expend additional ratepayer dollars to clean up the parks and eradicate pest plants that are dumped. Please report offenders to Council on +64 3 546 0200.

Ministry of Health - Public Notice

Some plumbing fittings have the potential to allow minute traces of metals to accumulate in water standing in the fittings for several hours. Although the health risk is small, the Ministry of Health recommends that you flush a mugful of water from your drinking-water tap each morning before use to remove any metals that may have dissolved from the plumbing fittings. This simple precaution is recommended for all households, including those on public and private water supplies.

Please clear stormwater grills

This is a permanent notice posted 16 November 2006

Heavy rain is forecast from time to time in Nelson, so the Nelson City Council is asking residents to clear leaves and other rubbish from any stormwater grills near their property.

If sumps are blocked, rain water can quickly build up, adding to the risk of flood damage. Leaves falling and blocking the grills can be a problem. Spring and warm weather days are good times to clean them.