Flooding study confirms limited impact of drain maintenance

The Environment Agency selected a two-kilometre stretch of the Burstwick Drain as one of six schemes nationally to evaluate the effectiveness of maintenance.

The Agency stopped its 10-year rolling maintenance programme in the North East in the 1990s but since the floods of 2007 has faced repeated calls for more dredging.

The study showed that maintenance could increase the amount of water it carries – reducing the risk of flooding, but not “significantly”. It also concluded that work downstream of the tidal doors where the water runs into the River Humber was more beneficial than work upstream.

The EA said yesterday it was “putting money on the table” offering £30,000 every five years towards the £80,000 cost of dredging downstream of the tidal doors at Hedon Haven, where the Burstwick Drain meets the River Humber, and further down at Stoney Creek.

However other organisations including internal drainage boards and the East Riding Council will be expected to fill the gap.

Ron Smith, whose house was one of 130 to be flooded in Burstwick in 2007, and sits on a liaison panel with the EA, said: “The general perception was that the Burstwick Drain was clogged up the whole way through and that was the cause of the flooding.

“I 100 per cent agree that’s not correct. But I do believe had the outlet been dredged the flooding wouldn’t have been as widespread and affected as many homes. But of course it is very hard to quantify that.”

However he added: “Although the report is welcome I still believe the money would have been better spent dredging the outfall into the Humber.” Ralph Ward, clerk to the Keyingham internal drainage board, said the report didn’t say anything new but welcomed the fact it highlighted the need for silt removal in the tidal part of the drain. He said: “It’s like the bath – if you don’t take the plug out nothing can get out.”

The National Farmers’ Union’s environment and land use adviser James Copeland said the EA was moving in the right direction: “We are happy that they appear to be moving back from a scenario of completely stopping all dredging activities to what appears to be a format that is better for the agricultural sector.”

Yorkshire area manager for the Environment Agency, Craig McGarvey said: “We listened to people’s concerns about the impact of watercourse maintenance on flooding and set up this trial to scientifically test our understanding of the benefits.

“On Burstwick Drain, engineers found very little silt upstream of the New Burstwick Clough doors, and as a result dredging in this stretch would have minimal impact on flooding.

“Dredging downstream of the doors could make a difference to Hedon and Burstwick but the impact is limited to surface water or land drainage flooding.

“Instead, the results show that the new £3m schemes in Burstwick and Hedon will make a greater impact on reducing the risk of watercourse flooding to these communities.

“We will contribute towards any future dredging below New Burstwick Clough Doors, as part of a partnership arrangement.

“We will also continue working with other organisations including the Internal Drainage Boards and Yorkshire Water to see how the risk of flooding from surface water and land drainage can be further reduced for these communities.

In all the study cost taxpayers £132,000 – with £51,900 spent on surveying and monitoring wildlife including water voles, technical support (£30,300), project management (£25,800) and £24,000 on “stakeholder engagement.”

It concluded: “The modelling has shown that work within the upper channel at Burstwick Drain had little impact. Dredging work downstream of the tidal doors would be of greater benefit.”