While monitoring water quality at Te Waikoropupū Springs Friends of Golden Bay noticed that where Fish Creek flows into the Springs reserve it repeatedly had an unpleasant appearance and smell after rain events.
We thought it important to have an objective appraisal of the situation, so we undertook a programme of tests for bacteria.
Bearing in mind the recent outbreak of illness in Hawkes Bay, we initially tested for both Campylobacter and E.coli. We took samples during rain events when the problem was evident. We are glad to report no Campylobacter was found. However, the picture with E.coli is a different matter. We present the results in the table below.
E.coli Data to Date:
This table will be updated as new rain event samples are collected.
The units are given as ‘Most probable number’ of E.coli per 100 ml of water (MPN/100ml) which is the conventional measurement. For comparison, the recommended safe level for drinking is less than 1 count per 100 ml, and the safe swimming level has recently (and controversially) been roughly doubled to 540 per 100 ml.
We were shocked by the results and received help from TDC in identifying the source, which was confirmed by further analysis to be ruminants, e.g. cattle. TDC is at present working with farms upstream of the reserve on methods to reduce the problem.
We plan to add to the table as more results become available so that there is a good baseline to assess the effectiveness of whatever control works are undertaken.
For further consideration:
We gave the results to parties with an interest in the issue, see our letter toTDC, DoC, Takaka FLAG members, Fonterra and Manawhenua ki Mohua here. We have received some initial comments back, including:
“E-coli levels from farm runoff under rain events will always be high and exceed drinking and swimming water standards.” and “It is common to get between 1,000-10,000 E.coli/100ml, depending on the density of cows and timing of when the cows were last in the paddock. It is like where we were at with dairy shed effluent 20 years ago.”
This simple study by Friends of Golden Bay has once again underlined the linkage between the intensity of dairy farming, its profitability, and the impact on our waterways. Remedial measures may subtract from the area available for grazing and may be costly for farmers. Conversely, further intensification will mean more pollution of our waterways.
The question for the whole community to answer is what trade-offs we choose to make, and hence what quality of the environment we will live in.