News

Hexham cross-Tyne sewer pipe - TRT's ongoing role

21 May 2010

Attention, open in a new window.

Update for our stakeholders concerned about the impacts of the fractured main sewer pipe across the river bed at Hexham (downstream of Tyne Bridge, adjacent to Broomhaugh Island) we have made significant inputs to raising the alarm, emergency action, remedial action and restoration phases of the incident.

Our Fisheries Consultant and one of our Trustees have been regular visitors to the site and were instrumental in alerting the responsible authorities: principally Northumbria Water and the Environmental Agency (EA), in speeding up the emergency response and making regular checks on the works to divert the river and repair the pipe. During the whole sequence of events, we have been fortunate that river flows were low enough to permit efficient engineering (and fish rescues by EA) but high enough to provide reasonable dilution for the raw sewage which could not have be processed by Hexham Sewage Treatment Works (this was discharged to the south channel). EA have been very cooperative in, for example, providing statistics on the fish rescued and updating us on the chemical calculations they make about downstream dilution effects. The breach itself was repaired on Saturday 15th May. The phase to which we now return is that of providing technical guidance on the river bed stability and the physical habitat considerations of the removal of the coffer dam.

Prof. Malcolm Newson's geomorphological expertise is being fed into the engineering brief for this, both directly by our staff and via EA. In the longer term, the stability of this section of river has relevance to both the vulnerability of the sewage pipe and the impact of any improvement to fish passage planned for the apron of Tyne Bridge. It seems logical to TRT that, following the example of the re-engineered upstream water supply pipe beneath the Tyne, the sewer pipe should be better protected against scour in the longer term.