How two growers are using regenerative farming to protect water >More in John Hawkins Pressure to reverse excessive nitrate leaching into both the Wessex Water borehole and wider Poole Harbour catchments has led Dorset farmer John Hawkins to radically reshape his farm in the past three years. The borehole supplies up to 8m litres of water a day, but can be out of action for three to six months of the year because of excessive nitrogen, explains Tim Stephens, a catchment adviser for Wessex Water, who has supported Mr Hawkins closely during the transition. In total, about 2,000t of nitrogen from 400-500 farms, plus Wessex Water sewage works, enters the Poole Harbour catchment a year.