Horizons Regional Council monitors the water quality in the Waikawa Estuary on a weekly basis during the bathing season (1st November to 30th April inclusive) and the results from this monitoring are placed on the Regional Council’s website each Friday night. The monitoring is done at the footbridge. The results can be found at this link.
The results this summer show from 20 monitoring occasions there were 5 times that we would recommend that people do not swim as a result of high E.coli levels. In general these high E. coli levels were also associated with high river flows (in general, rainfall causing contaminants to wash off the land). The E.coli levels are not due to the formation of the sandbar or as a result of slower moving water but as a result of land use. This is one of the reasons that the Waikawa Stream has been identified in the Proposed One Plan as a priority catchment for the management of diffuse contaminants (the Proposed One Plan however is still going through the Environment Court process).
In terms of the sand bar formation this will not contribute to the water quality in the Waikawa Stream however, the sandbar is important in terms of estuary formation and providing more habitat within the Waikawa Estuary for flounder and for inanga spawning which in turn provides recreational opportunities.
Hopefully this answers any concerns you have regarding the water quality in the Waikawa Estuary – the weekly monitoring will continue till the end of April this year and will then recommence in November with all the information being provided at the above website.