Sir - I'd like to thank the community service workers under Doug Carslaw's supervision for their efforts in clearing public rights of way in the grounds of the Churchill hospital (Report, November 24). I use the path network every week and it's great to be able to use paths again which have been obstructed for a long time.

However, the team are going to have a much tougher job clearing another right of way which the Churchill has buried under Tarmac and concrete. The Churchill applied for a diversion order to reroute it along the east side of the Boundary Brook wildlife corridor and past the pond.

Unfortunately the development's new access road encroaches too far on to the wildlife corridor to fit the footpath in on its intended line. The pond is now hemmed in by a high, concrete-reinforced bank. To give an idea, it's similar to the one at the back of Tesco's car park next to the ring road. The developers have further weakened the wildlife corridor by bulldozing away topsoil and the natural vegetation right up to the bank of the brook, with a view to turfing it, and they appear to be preparing to Tarmac some of the area. People did not object to the application to divert the original right of way because they recognised the need to build the new cancer centre and they trusted that the wildlife corridor would be protected. That trust was misplaced and this does not bode well for the fate of the wildlife corridor on the other side of the brook - in Warneford Meadow.

Jo Aldhouse, Oxford