[citation needed] The tanks are fed by several springs including one which becomes the Land Yeo.
The first opened in 1852 to store the water from the newly finished "Line of Works", but within two years it developed a leak and had to be drained for repair, causing serious disruption to Bristol's water supply.
[1] Over the following decades, work was undertaken to improve the water quality.
[2] During 1962 maximum output was increased from 26 million imperial gallons (120,000 m3) to 31 million imperial gallons (140,000 m3) a day by lowering the outlet of the filtered tank and duplicating inlets to the seven filters which received microstrained water.
[citation needed] Fishing (under permit) is generally for rainbow (Oncorhynchus mykiss, formerly Salmo iridia) and Brown trout (Salmo trutta morpha fario and S. trutta morpha lacustris).