Somerset councillors have agreed to provide an extra £603,000 to ensure that upgrades to one of the county’s key flood defences can finish.

The River Sowy and King’s Sedgemoor Drain form a relief channel for the River Cary and the River Parrett, taking excess water off the Somerset Levels near Langport and enabling it to flow out into the Bristol Channel north of Bridgwater.

The Somerset Rivers Authority (SRA) has been overseeing improvement work to both man-made channels, ensuring they have sufficient capacity to cope with a wet winter and beyond.

The SRA board voted in Yeovil on Friday morning (July 22) to allocate further funding to ensure all the work can finish on time by November.

Work began on the River Sowy and King’s Sedgemoor Drain improvements in September 2021, with the projects being carried out by the Environment Agency (EA) and its contractor Kier.

The improvements include raising low spots in the existing riverbanks, forming new banks where needed, excavating certain sections to prevent the channels from silting up and upgrading “outfall structures” like the Dunball sluice.

During the work, a substantial amount of vegetation has been cleared from the site of both channels to discourage birds and water voles from nesting, which could hold up other elements of the flood prevention programme.

The final elements of the scheme, concerning Parchey, Cossington and Chilton, are aiming to be finished before the winter to prevent any further disruption to local wildlife (such as wintering birds).

However, due to high inflation across the construction sector – which has affected numerous projects across Somerset – additional funding had to be agreed to ensure this deadline could be achieved.

EA project executive Gary Cutts said in his written report to the board: “The biggest risk to delivery remains the industry-wide issue of shortage of resources and inflationary pressures.

“This risk persists despite working with the contractor to secure earthworks plant, drivers and placing orders for outstanding materials early.

“The current forecast total outturn for the scheme is £8,349,000, resulting in a projected £603,000 shortfall of funding to complete the scheme.”

The board voted to approve the additional funding, with a further update on progress due to come to the next board meeting in the autumn.