Raetihi pool painted Whangaehu River quality may be improved

Ruapehu Bulletin, Volume 8, Issue 371, 29 January 1991, Page 8

Raetihi pool painted Whangaehu River quality

may be improved

Raetihi's school pool is being painted with the 'help of Raetihi Access schemef trainees, who decided to provide voluntary labour. The women are all trainees in the Ceramic Access course run by Honey Winter with Vai Marumaru. They normally spend three days a week on ceramics training and Thursdays they have a community day

when they get out and try to help various sectors of the community such as senior citizens or the schools. If they have no project on at the time, they often have speakers visit to talk on social issues that affect them, said the controller, Honey Winter. Mrs Winter said they did not charge the school for the work, that

it was voluntary. Mrs Winter said that contrary to what many people think, the Access trainees were not paid any extra on top of their unemployment benefit for attending the course and that they were not paid for the community work they carried out. The next stage of the project is to paint the murals in the pool which are to be designed by Rana Te Huia.

The appearance and possibly the smell of the Whangaehu River may improve in the future if a study of the river water and Wintones Pulp Mill effluent is successful The study is a cooperative programme between Winstone pulp International's Karioi pulp mill and the M anawatu- Wanganui regional Council and it could result in the Whangaehu River's year around appearance being improved. It is a voluntary programme, instigated by Winstones, and aims to reduce the discolouration of the river which occurs during periods of low flow. This usually happens during the summer and autumn months and is characterised by a milky-grey turbidity. "We would like to discover whether modification to our treatment regime will result in an improvement of the

river's water quality," says Technical Manager Philip Wilson. The present smell of the area by the Tangiwai Bridge is not the river itself but comes from the mill's aerobic and anaerobic settling ponds, said Regional Council officer Sue Dewing. She said this smell may be reduced following work Winstones are carrying out on the quality of the effluent. She said changes in the system that may follow the study could see a reduction in the smell. Anne Marie Westcott, scientist for the Regional Council and Caroline O'Rourke, process engineer for Winstone's, are selecting suitable sites for the

tests located along the Whangaehu River and its tributaries. It is expected that the monitoring programme will take from 18 months to two years. The investigations will be conducted throughout the year and cover periods of high and low water quality on the river. "We are interested in seeing what impact aeration of the water is having and whether a reduction in it would result in a reduction in the river's colouration." Aeration is part of the mill's effluent treatment process. Studies have shown that operation increases the colour and turbidity of the effluent. This treatment stage is used to reduce the impact Turnpage 9

Whangaehu water may be improved

From page 8 of the effluent on the river's dissolved oxygen levels. "However it would seem that the river's own rapid flow aerates the water sufficiently and we may be over doing it by aerating the effluent ourselves," said Mr Wilson. Initial laboratory trials have already been done and these have indicated that there would be no major imp^ct on the river if aeration was to cease. "There is no fish life in the water due to chemicals coming naturally from the crater lake, so we are largely concerned with the aesthetic qualities of the river. If an improvement in the colour and turbidity can be achieved and the appearance of the river improved then we will be very satisfied." Barry Gilliland, acting manager, Investigations and Monitoring for the Manawatu- Regional Council, says:"This is an excellent opportunity to work with a major industry within the region to achieve a positive impact on one of our rivers."