Environment Waikato has pinpointed the location of high bacterial counts in the Waikato River to an area six kilometres downstream of Cambridge.
But the Council is still narrowing down a range of possible point sources. Intensive sampling of the river over the past two and half weeks has found continuing high levels of faecal coliforms in the water – but pinning down the exact source is in its final phases.
The levels are making the river unsuitable for swimming from Cambridge downstream, but levels upstream are well below safe swimming guidelines.
Resource Information Group Manager Tony Petch said the levels were now higher than found nearly three weeks ago, but the Council is pleased to have made progress and was looking into known “point sources” – those which flow from a defined area.
“Finding the source has helped explain the unusually high levels at Narrows Bridge seen over the last year, but will not dramatically improve the swimmability of the river within the Hamilton reaches.”
He said the Council was working with Hamilton City to resolve this issue.
“These incidents highlight the sensitive nature of the Waikato River soils and we have to be careful about how we manage all forms of discharge in this area. This includes general runoff from pastoral land, septic tanks and urban areas.”