A joint venture between Costain, Galliford Try and Atkins has won an extension to a £400m utilities framework contract.

The group said it had secured an extra five years on its AMP4 framework agreement with United Utilities, which will run from 1 April 2010 to 31 March 2015.

Under the deal, which began in 2005, the joint venture is responsible for non-infrastructure capital delivery works in the company's Southern area and the work will involve improvements to water processing plants and improvements to clean and waste water processing plants.