They have agreed that Northumberland County Council Planning and Environment Committee Chairman Trevor Thorne should write a strong letter to Northumbrian Water (NWL) outlining fears and urging the company to act.

Morpeth Flood Action Group spokesman Tom Smith had asked the committee at County Hall on Tuesday evening to refuse permission for expansion of the town's sewage treatment works until the whole system was modernised.

He said that because councillors had no say on whether or not sewers were improved, this was their only chance to take action.

Company spokeswoman Mary Campbell told the meeting: "NWL do understand the residents' concerns regarding the need for improvements to the sewerage and drainage network in Morpeth.

"NWL is committed to the analysis of and improvement to the network and is currently working with partners to ensure that these programmes are co-ordinated with improvements to the surface water and drainage networks."

Members voted unanimously to approve the works expansion to accommodate future house building and to write to the water company.

Morpeth councillor David Moore moved approval of the scheme, but suggested writing to NWL asking what it was doing "to give some peace of mind to the people of Morpeth".

Coun Thorne said he would write a strongly-worded letter encouraging Northumbian Water to communicate better.

Mr Smith had put documents to the committee charting repeated floods of sewers in low-lying parts of Morpeth, not only in 2008, but also episodes a year ago.

He said people in Morpeth had a sleepless night when there was heavy rain, worrying for their homes.

In the town's ageing system the sewers also take surface water from roads and the action group wants the two networks separated.

Coun David Woodard said 1,000 homes and businesses had been inundated with sewage and contaminated water in 2008 and people needed to be confident that would not happen again.

He wanted to add a condition requiring NWL to explain how it would improve the network.

He said: "It's essentially not possible for this planning application to be considered in isolation from the network that affects it."

However, it was ruled out by officers