Evaluation and improvement of the flood rainfall network

Phil Downes - Canterbury Regional Council NZ , 28 May, 2003

The Canterhwy Regional Council operates a hydrometric network of 77 surface water level stations; 44 of which are telemetered. There are also 67 rainfall monitoring stations, 57 of which are telemetered. The Council has ยท developed a Quality Assurance system that outlines the frequency of visits. The acceptable amount of missing record in any year. and the quality of the data for the hydrometric network.

The present economic climate demands reduced costs while still providing the same level of service.
At present the rainfall stations are visited every two months, with checks being carried out on the radio communication links. the rain gauge (tipping bucket) calibration and the storage gauge (total cumulated rainfall since the last site visit). All of these factors are important in the maintenance of rain gauge efficiency and the reduction of missing record. The aim is to reduce these site visits to every four months, hence significantly reducing the operational costs. This is to be achieved by automating the check gauges at the more critical sites.