252 



But without the interposition of very larg;e storeuge reservoirs 

 to make the flow uniform, the effect could not be produced, and 

 the settlement of the question of supply remains as distant as 

 ever. For instance, 272 square miles of drainage is attained by 

 the Thames and its tributaries, just below Lechlade, and here 

 the minimum summer flow of the Thames is under 20,000,000 

 gallons per diem, or but one-fifth of the required quantity. 

 Again, the minimum summer flow at Hampton, being the result 

 of 3676 miles of drainage area (see the pubhshed Report of the 

 Commissioners for Preventing the Pollution of Rivers) is but 

 362,000,000 gaUons per diem, being at the rate of 26,700,000 

 gallons per 272 square miles, and Kttle more than one-fifth of 

 the required quantity, and at Castle Eaton only a few miles 

 above Lechlade, Mr. Beavender found the most insignificant 

 quantity of water passing down the river in the summer of 1864. 



Besides this, any scheme of supply involving the abstraction 

 of the whole surface waters, having regard to riparian and other 

 interests, would be imperfect or impossible, and it woidd be 

 necessary that the reservoirs should be large enough, not only 

 to provide for the main supply to the metropoHs, but also to 

 maintain the dry weather stream during periods of drought. 

 Now I know not where such extensive reservoirs could be formed, 

 either in the valley of the Thames, or of its early tributaries, 

 and it should be also observed that the elevation of the Thames 

 at Lechlade being but 234 feet above the sea, is iAsufficient for 

 seiTices in London by gravitation only. 



On the subject of storeage, Mr. Bateman takes his usual bold 

 comprehensive view, and I think he establishes the facility of 

 the construction of his proposed reservoii-s in the district which 

 he selects. His gathering grounds would cover 204 square 

 miles, and his reservoirs would hold 35,000,000,000 gallons, and 

 would supply London with nearly 200,000,000 gaUons per diem, 

 after deducting compensation to the rivers affected, at the rate 

 of one-fourth of the assumed rainfall for 140 days of drought. 



Messrs. He mans and Has sard ha\dng regard to prospective 

 increase in the requirements of London and some supply along 

 their line of conduit, contemplate supplying 250,000,000 gallons 



