Sewage pollution in Le Roys Bush 23 Nov 2014

Proposed Programme of Prevention, Education and Restoration

Actions that we ask the Kaipatiki Local Board and our Auckland Councillors to pursue (presented to KLB Wed 10 December 2014):

1. working with the Birkenhead Town Centre Association to raise awareness about building owners and occupants

2. working with the compliance officers at Auckland Council to ensure that all grease traps are regularly cleaned and monitored

3. identifying an improved programme for proactive grease trap management and control

4. undertaking a public education programme both via the press and through local schools to make people more aware of the need to keep detergents, road runoff, swimming pool and other chemicals out of stormwater drains

5. marking storm water drains with stencilled signs to remind people of the need to protect the fish and other fauna in the streams

6. increased water testing in the Le Roys Bush stream and Little Shoal Bay

7. setting up appropriate programmes for school children (both primary and secondary if interested) to work with WaterCare educators and scientists to understand monitoring programmes

8. ​working with Northcote College to study the pools below Highbury to identify if any fish are left in the stream.

9. looking into ways to remedy the damage caused

10. asking the Kaipatiki Local Board and Auckland Council to resume SwimSafe monitoring of Little Shoal Bay water quality

11. identifying a programme to accelerate the management of wet weather sewage overflows across the reserve including in the wetland.

The KLB meeting on 10 December seemed receptive to this proposal although noted that the cost of water quality monitoring is very high. The LRB representative noted that Northcote College may be interested in taking the samples as part of their science programme. Board members seemed to think this could be worth pursuing.

Please send any other ideas to leroysbush@gmail.com

Note as at 17 January 2015: we are still awaiting further information from Council about what actions will be taken.

We have received one email with a copy of water pollution brochures from Council - see notes and attachments to the page Erosion, flooding and & pollution

Details and photos of the overflow

On the weekend of 23 November 2014, a sewage leak started, possibly on Friday 21 November, and ran until Sunday when it was discovered by a group of volunteers clearing weeds up near the Highbury Shopping Centre.

The overflow was caused by commercial fats building up in the sewer line running down behind apartments on Onewa Road below 57-63 Birkenhead Ave.

Investigation by WaterCare Ltd found that at least one grease trap was completely full and clearly had not been maintained. The building concerned is owned by a significant NZ company and one wonders what programme they have in place for its maintenance.

The sewage overflowed from a manhole in the basement of the Westpac Building and by the time it reached the Le Roys Bush stream the flow was about 3 metres wide. As it ran down the upper Le Roys Bush stream where banded kokopu (adult whitebait) live and breed, it filled their pools with brown effluent, scum and froth.

Kokopu are very sensitive to pollution - and there is a risk that kokopu population may be seriously impacted by this spill.

Below are some photos showing the pollution at various stages down the Le Roys Bush valley from the Westpac Building down to below Enterprise Street (photos courtesy of Dr Kit Hustler, Northcote College)

The Northcote College science team sampled the fish in the upper parts of the catchment of Le Roy’s on Saturday night and caught 8 Banded Kokopu, 6 of which were living there prior to the sewerage overflow. The other 2 were probably also living there, but were quite small fish and I’d not caught them before. The water in the stream still has a greyish tinge to it and in a couple of pools there was a film on the top.

There is the possibility of a slow impact on the fish in the stream, so we are not out of the woods yet it seems. We look forward to WaterCare getting water quality monitoring up and running asap.

This page is a work in progress - more photos and commentary will be added later.

If you have any questions, please email LeRoysBush@gmail.com