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Title: River Hiz : alleviation of low flows
Author: Environment Agency Anglian Region
Document Type: Monograph
The River Hiz flows northwards through Hitchin in Hertfordshire, where it is joined by two principal tributaries, the Rivers Oughton and Purwell. All three are fed by Chiltern chalk springs. The valley of the River Hiz between its source at Wellhead and Hitchin town centre is a popular area for walking and horse riding. Water has been taken from underground supplies held in the chalk around Hitchin for over a century. The amount taken has increased over the years to meet the needs of a growing local population. As demand has increased and rainfall patterns have changed, spring flows have reduced in the upper Hiz, and the stream has been drying up, particularly during periods of drought. The spring-fed wetland on Oughtonhead Common has deteriorated to such an extent that it lost its status as a Special Site of Scientific Interest in 1970. The Environment Agency, formerly the National Rivers Authority, and Three Valleys Water have worked together to find solutions to problems caused by low flows. The River Hiz is one of three low-flow rivers in the area whose problems are being addressed by Three Valleys Water; the first successfully completed scheme was on the River Ver in Hertfordshire, followed by a scheme to improve flows on the River Misbourne in Buckinghamshire. Following investigative work, a number of options were identified. These included river support from groundwater, recirculating river water from downstream, improved wetland and river management, relocating public water supply boreholes and importing bulk water supplies from Grafham Water Reservoir, near Huntingdon, Cambridgeshire.
Publisher: Environment Agency
Publication Date: [after 1996]
Publication Place: Peterborough
Subject Keywords: RiversWater levelsFlow rateDroughtWater management
Geographic Keywords: EA AnglianUpper and Bedford Ouse catchment
Extent: n.p. [5]
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