LIVES were put at risk and raw sewage spilled out when two manhole covers in a York car park blew off during recent floods, a councillor has claimed.

Cllr Andy D’Agorne said someone walking across the St George’s Field car park in the dark could have fallen through a hole into a sewer five metres down.

He said he had been pressing Yorkshire Water to address problems with the malfunctioning sewer for the past year but it had failed to tackle the underlying cause.

He said information given to him by a City of York Council engineer suggested that Yorkshire Water was failing to tackle a blocked vent and inadequate design.

“It is not an exaggeration to say that lives could be at risk if anyone was to walk through the floodwater in the car park at the time when, or after, the manhole covers blew off because of the build up of pressure,” he said.

The Fishergate councillor, who is council deputy leader, said the problems related to the Castle Mills pumping station, which operates when the River Ouse is flooding badly to prevent a breach of flood defences by reverse sewer flow.

He said the engineer had told him that pumping pressures were not being relieved, due to either a blocked vent or an incorrect pumping operation.

The engineer had said: “Two access covers - five metres deep- in the public car park were blown off and sewage debris flooded the area.”

Cllr D’Agorne contacted The Press to raise his concerns about the manholes after the paper had reported the concerns of cyclists using a riverside cycle path and footpath which was blocked by the same sewer problems.

York Cycle Campaign called then for urgent repairs to the burst sewer, saying cyclists and pedestrians using the path near Skeldergate Bridge - which provided a heavily used route into the city centre from Fishergate, Fulford and the Millennium Bridge - were being forced by barriers to navigate muddy verges on either side.

Cllr D’Agorne said yesterday it was the responsibility of Yorkshire Water to sort out the problems but he felt it looked increasingly likely that it hoped to pass the problem on to the council as part of the cost of a proposed new car park in St George’s Field.

He said the council engineer had said that a ‘syphon chamber’ in the cycle path alongside the river was damaged by significant uplift pressures, bodily lifting the whole cover, frame, concrete cover slab and adjacent concrete, presenting a significant hazard to the public, and the cycleway remained closed to the public without a diversion being provided.

The engineer had suggested Yorkshire Water should provide a temporary diversion route and reconstruct the syphon chamber, with a replacement vent stack and maintain the vent stack to prevent a fat build up.

A Yorkshire Water spokesman said it took the safety concerns about the car park extremely seriously and would continue to work closely with the council on all such issues, but had no intention of passing the problems on to it.

“We will be installing a frame and plate and a new cover will be put in place on the cycle path as soon as possible,” he added.