The valve well and Culvert will enable the Valves and Syphon Forward to be always within reach for examination and repairs.
I propose to construct the Rye Wash as shown on the Stan × 5' and calculate that it will discharge 11,016,000 Cft of Water per hour or nearly 6 in: per hour rain fall on the Gathering Ground.
It would appear to be impossible that such a rain fall, 6 in: per hour could ever fall, there has however been a fall of 2.6′′.
The Existing Malis Weir which is 120 feet wide and may be of 400 Square feet in place of 300 Square feet which has actually been found to be required. Culvert under the Rye Wash is provided for in case of emergency, and the sluice Valves in the Valve Well will discharge a further 2,091,600 Cft per hour.
During the Construction of the Embankment a Temporary Bye Wash must be formed to carry off flood Waters, and the nature of the Ground will necessitate its being placed where the permanent Rye Wash will be formed but of course at a lower level, probably 15 feet above the bed of the Reservoir, the level at which it is proposed to construct the Tail Culvert. I should hope to be able to complete the Embankment to this height before the rains set in.
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