Castle Irwell Flood Detention Reservoir—Design and Construction

Castle Irwell Flood Detention Reservoir is a new offline flood storage reservoir, located in Salford, approximately 2 km upstream of Manchester city centre. The reservoir sits in the lower reaches of the River Irwell catchment on the former site of Manchester Racecourse. The project client is the Environment Agency. The reservoir is fully bunded within a meander on the River Irwell by a 2.3 km long, 3 m high, zoned earth embankment. Inflows into the reservoir are controlled by a grass reinforced inlet weir at the upstream end and outflows are controlled through twin, automatically actuated, 1.5 m square penstocks. Construction commenced in February 2015 and is due to be completed in 2016.