Completely agree with your views on the south east however, along with the existing housing stock, the demand for housing in the Christchurch to Salisbury conurbations is large. Admittedly much of it will be apartment blocks, with small semi-detached houses on small developments making up the rest. When I lived in the New Forest 20 years ago I worked inside the M25 as did many of my friends and work colleagues. The vulnerability of the Avon catchment is the combination of a slow recharge rate in the aquifer (which needs large areas of grassland and pasture to do this effectively), and the loss of precipitation through surface runoff as a result of increasing amounts of tarmac, concrete and housing. When low flows are combined with increasing temperature, silt and nitrogen from both agriculture and effluent exponentially increase algae growth which adds another dimension to an already stressed ecosystem. All this mitigated for in the EU Water Framework Directive - which may not apply to the UK from January the first 2021.
The Equilibrium Phosphorus Concentration (EPC0) of river bed sediments has been measured for a wide range of agricultural subcatchments and main river…
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