VOL. xviT. (3) WATER SUPPLY OF GLOUCESTER 347 



GEOLOGY AND WATER SUPPLY 



BY 

 L. RICHARDSON. 



RoBiNSWOOD Hill Reservoirs.— These reservoirs, as 

 stated above, were constructed by a Company in 1837-8, and 

 were purchased from the Company by the Corporation, under 

 the Gloucester Water Act of 1855, for £18,500. 



Storage capacity : upper reservoir . . 9,000,000 gallons 

 lower ,, . . 1,000,000 ,, 



Total 10,000,000 gallons 



The gathering-ground has an area of 260 acres. Part of 

 it is a depression in the side of the hill (commencing about 

 the horizon of the Capricornus-Beds of the Lower Lias), which 

 extends and narrows upwards between two shoulders of 

 Marlstone, terminating at the foot of the slope where the 

 Cotteswold Sands begin ; but a considerable quantity of water 

 is collected and brought round the contours of the hill in pipes 

 to the reservoirs. Most of the water is derived from two 

 horizons— (i) the base of the sandy beds of the Middle Lias 

 and (2) the base of the Cotteswold Sands. 



The springs have a minimum flow of about 25,000 gallons 

 per day. 



Permanent hardness . . 9-1 degrees 

 Temporary ,, . . ii-2 



Total = 20-3 degrees 



WiTCOMBE Reservoirs. — These reservoirs (fig. 2) were 

 constructed under the powers of the 1855 Act. 



The formal opening of the Witcombe Works took place 

 on September 20, i860, when the water was turned in from 

 the upper to the lower reservoir, the works being completed 

 z 



