Thirsk market place's huge "black hole" is to be filled in by next Friday - and that's a promise.

Yorkshire Water has made a pledge that its £380,000 project to build a sewer under the market place will be completed by the weekend before Christmas.

The scheme, which will ultimately improve the quality of Cod Beck by reducing the amount of waste water being discharged into it during times of heavy rain, has involved a massive holding tank - the length and width of 1 double-decker buses - built below the centre of the market place.

The work will be finished by next Friday. However, work to build an underground sewage chamber in nearby Blakey Lane has been slightly delayed due to a gas main needing to be diverted.

Yorkshire Water project manager Rob Bainbridge said: "This is a very complicated project, but we are progressing to plan. We have made assurances we will be finished by December 19 and finished we will be.

"I know this scheme has caused disruption for residents and visitors and for that we apologise. However, once completed this work will bring significant environmental improvements to Cod Beck."

Thirsk Chamber of Trade has been inundated with complaints of disruption and loss of earnings during the project, which has also included digging up most streets approaching Thirsk.

The work was originally planned during the summer but it was agreed to delay it until September to avoid the tourist season. At that time it was promised the work would be done before the run-up to Christmas.

Chamber chairman Don Moore sought assurances form Yorkshire Water that the work will be complete before Christmas and asked the company to issue a public statement saying when it would be finished.

A spokesman for Yorkshire Water said: "We agreed to move back the work to avoid the tourist season and did expect to finish before now. Unfortunately, certain problems were not taken into account at the time and we appreciate the concern as 20 car parking spaces are being taken by the work. We will ensure completion in time for the last, most important week for shoppers.