HC Deb 09 December 1971 vol 827 cc387-8W
Mr. Hardy

asked the Secretary of State for the Environment what is his estimate of the cost of providing a reservoir or a desalination plant each capable of producing 30 million gallons of water per day; and what would be the cost per 1,000 gallons of water from each of these two sources.

Mr. Graham Page

The cost of water from reservoirs varies substantially according to location and other physical characteristics. The cost of desalted water depends upon the process used and the location of the plant in relation to the area where demand arises. A comparison in the terms of the hon. Member's Question therefore would not mean very much; but in their Report on Desalination in England and Wales, published in 1969, the Water Resources Board calculated that in general the cost of desalted water for a considerable time to come would be twice the cost of water from conventional sources. Changes in technology could alter this ratio, and I keep the situation under constant review.

Mr. Hardy

asked the Secretary of State for the Environment what is the number of acres taken up in the last five years for the purposes of maintaining or increasing water supply; and what proportion of this acreage was classified as grades I, II or III of agricultural land.

Mr. Graham Page

In the five years ending November, 1971, enabling powers were granted for the construction of impounding reservoirs involving flooding of about 5,100 acres. None of this land was classified as Grade I agricultural land. About 80 per cent. was classified Grades II or III, the greater part falling within Grade III.

Mr. Hardy

asked the Secretary of State for the Environment if he will conduct a feasibility study into the question of a desalination plant to supply water for intermittent use in periods of dry weather, in order to reduce the need for increasing the number of reservoirs or the rate of extraction of water from rivers in the Yorkshire region.

Mr. Graham Page

No. In 1969 the Water Resources Board considered the possibility of desalination for Yorkshire and came to the conclusion that detailed investigation would not be justified, because it appeared that the cost of water produced by distillation of sea water would be much more than by conventional schemes.