Environment Waikato is currently undertaking repairs to one of its pumps in a pump station on the Waihou Valley Flood Scheme, after cracks were found in the pump casing.
In late January, one of the 3.4 cumec pumps at the 18 year old Roger Harris pump station, part of the flood protection scheme, was lifted for a programmed maintenance check. Several cracks were found in the lower sections and bell housing and the metal was corrosion pocked.
Environment Waikato Operations Committee was told of the actions being taken to repair the pump to ensure it is effectively repaired and returned to full operation as soon as practicable.
The lower three sections of the pump were cast of a special chemical resistant metal with a high nickel component which could not be welded, rather than the normal cast metal as in other stations.
The Australian manufacturers had been approached to find out the cause and if it could be repaired effectively. The alternative was to replace the critical component, which would cost about $28,000.
As an interim measure until final repairs are undertaken, the removed pump has been reinstated to ensure pumping standards were not being compromised significantly. The Committee also heard that the other pumps in this drainage area were presently providing 90 percent of the scheme design standard capacity.
A newly repaired pump is programmed to be fully operational by the end of September.