HC Deb 18 April 1973 vol 855 cc125-7W
Mr. Trew

asked the Minister of Agriculture, Fisheries and Food whether he will ascertain from the Greater London Council and the Kent River Authority what progress has been made on the design of the flood barrier across Dartford Creek; what decisions have been taken about the type of barrier; and what the latest estimates are of starting and completion dates and cost.

Mrs. Fenner

An investigation into alternative designs of flood barrier for Dartford Creek has been completed by the engineering consultants to the Kent River Authority.

There are three feasible possibilities: drop gates, a rising segmental gate, and rotating sector gates. The estimated cost, at mid-1972 prices, varies from about £2 million to £2¾ million according to type. Of the three types the Kent River Authority prefers the drop gate type and has invited observations from those authorities and other bodies with an interest. The contract is expected to be let in the second half of 1974, and the work completed before the Thames barrier becomes operational in 1978–79.

Mr. Trew

asked the Minister of Agriculture, Fisheries and Food whether he will ascertain from the Kent River Authority what progress has been made on the improvement of flood defences in the Darent Valley.

Mrs. Fenner

Flood alleviation schemes for Westerham and Chipstead have been approved for grant within the past year. The first is in progress. The second is scheduled to start later this year. Approval has also been given to preliminary investigations at Dartford and we are now considering outline proposals for the flood alleviation scheme there.

Mr. Trew

asked the Minister of Agriculture, Fisheries and Food what progress has been made on the construction of the flood defences downstream of the Thames flood barrier and arising from it; what the latest estimates are of completion dates and of cost; and if he will make a statement.

Mrs. Fenner

Flood defences downstream of the Thames barrier are the responsibility of the Greater London Council and, further downstream, the Essex and Kent river authorities. The tentative estimate of cost, at mid-1972 prices, is of the order of £110 million.

The GLC has made a start of the work in its area. It will be completed by the time the barrier becomes operational in time for the 1978–79 flood warning season.

With the help of engineering consultants the Essex and Kent river authorities have undertaken several preliminary investigations and studies. Outline designs for the improved defences have been prepared and are under discussion with the frontagers concerned. Creek closure schemes are well advanced.

Before the barrier becomes operational the two river authorities should have completed the necessary improvements to the downstream defences in areas of comparable importance to London or where there is appreciable risk of loss of life or damage to property.

Mr. Trew

asked the Minister of Agriculture, Fisheries and Food what progress has been made on the Thames flood barrier and what the latest estimates are of starting and completion dates and of cost; and if he will make a statement.

Mrs. Fenner

The barrier site is already being cleared to allow the erection of control buildings and the provision of accommodation for contractors. Contracts for diversion dredging, main civil works, gates and machinery will be placed in sequence. The barrier is expected to be operational in time for the 1978–79 flood warning season.

The latest estimate of cost is of the order of £55 million. This figure, based on mid-1972 prices, can however only be tentative at this stage.