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In the late 1960s many long-standing valley residents considered that the river flow was decreasing. This unease heightened through the 1970s & 80s when much of the river dried in some years. Suspicion naturally fell on water abstraction at Stubhampton & Shapwick. Well attended public meetings in 1991 & 1996 showed the real concern for this problem & the possible resulting loss of fauna & flora.
From the outset the RTPS, chaired by Rose Mainwaring-Burton, recognised that the low flow problem was more complex. It required understanding before the environmental issues could be assessed. Approaches to the then newly formed Environmental Agency (EA) for assistance quickly showed that, with their large remit, it would be necessary to raise the profile of the Tarrant in their eyes. The RTPS decided that co-operation with the authorities was the best way forward.
In 1998, with aid from the EA, financial support from North Dorset District Council & about £1,000 raised locally, a consulting hydrologist reported on the River Tarrant. His report, a very useful state of play summary, suggested that Stubhampton abstraction was not a major cause of low flow but that the Shapwick boreholes may be increasing the frequency & severity of drying out of the lower Tarrant. His argument was qualified as it was not known if that stretch of river was perched or influent. He hinted that it might not be influent based on some data from a well at Tarrant Crawford Abbey and flow in the river. The flow at Tarrant Rushton, where maximum flows are usually recorded, was plotted against that at Tarrant Crawford when data for both was available and a regression line fitted. Using this line enables the flow expected at Tarrant Crawford to be predicted from the measured value at Tarrant Rushton. Subtracting this predicted value from the actual flow measured at Tarrant Crawford enables the flow gain or loss to be Go to home page
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