Report No FR/D0004

THE BENEFIT-COST OF HYDROMETRIC DATA - RIVER FLOW GAUGING

FR/D0004

Mar 1991

SUMMARY

The benefits and costs of the UK river gauging network have been compared on the basis of information obtained from seven organisations (five water authorities in England and Wales, one river purification board and DoE (NI)). Although there was some uncertainty in the valuation of benefits, the minimum benefit/cost ratio was estimated as 1.2 (best estimate 2.3).

The total revenue and capital costs for the UK network were estimated to be £9 million/ annum. Capital costs include the costs of providing replacement stations and instrumentation. Revenue costs include the cost of collection, processing and publication, together with allowance for administrative overheads.

The main quantifiable benefits were associated with:

(a) the risk of climatic change or other factors causing a significant change of river flow (assuming that the gauging network had been abandoned),

(b) water authority operations, including the supply of potable water, and

(c) irrigation. Only small benefits could be quantified from flood warning and flood alleviation and, at present, none at all from consents to discharge effluent.

Recommendations are made concerning various aspects of the study:

(a) the need for similar benefit/cost evaluation of other aspects of the water cycle and the virtue of repeating the present exercise at intervals of 5 years,

(b) producing a definitive list of flow gauging sites, classified by type, and deciding the optimum size of the total network,

(c) Publication of river gauging data by the NRA,

(d) the economics of providing streamflow data and the reliability of individual components of the network system.

Copies of the report are available from FWR, price £15.00, less 20% to FWR Members.