Media Release - 04/03/08
The Canterbury District Health Board today voted to accept the independent Health Impact Assessment of the Central Plains Water Scheme, subject to some changes to the draft report produced by the DHB’s Community & Public Health division.
The Health Impact Assessment concludes that there is a risk that the health of Cantabrians could suffer if the CPW scheme goes ahead as proposed. In particular:
• An increase in nitrates in groundwater could lead to a risk of cases of “blue baby syndrome”* in bottle fed babies.
• If rising groundwater levels cause septic tank failures, this could give rise to a risk of infectious disease from some wells.
• There is a risk of contamination of the Christchurch aquifer.
• There is a convincing positive health impact derived from increased wealth, but this may be limited to relatively few people in the short to medium term.
One of the authors of the HIA report, Medical Officer of Health, Dr. Alistair Humphrey said, “the team that carried out the Health Impact Assessment concentrated on the best available evidence for certain key areas. The evidence is never going to be absolutely clear cut in these areas, so the conclusions of the report focus on risk rather than absolute certainties. However, the District Health Board has a responsibility to take a precautionary approach where the health of more than 400,000 people is concerned. Their decision today clearly indicates that they are not prepared to take a chance with our health, irrespective of what the potential economic benefits might be.”
Evon Currie, General Manager of Community & Public Health said, “the DHB through C&PH has an ongoing relationship with ECAN and the local TLAs to work with the farming industry to mitigate the effects of intensive agriculture in general and increased nitrates in particular. This work is ongoing and will continue irrespective of the outcome of the hearings on the CPW scheme.”
*Blue baby syndrome, or methaemoglobinaemia, is a rare condition in which nitrates from drinking water are converted to nitrites in the stomach. These then bind to haemoglobin, preventing the transport of oxygen by those blood cells. Bottle fed babies (whose milk is made up from drinking water) under the age of three months are most vulnerable, since nitrites bind to foetal haemoglobin (the type of haemoglobin babies are born with) particularly strongly. There has been one suspected case in New Zealand, but the illness is difficult to distinguish from other forms of baby death, so the true rate is not known.