Difference draining the Fens has made
The lowland drainage schemes of John Rennie and his contemporaries turned large areas of marsh land into farmland. Hundreds of previously unproductive acres could now be used to grow crops.
Creating these new areas of farm land played a large part in feeding growing urban populations – particularly in the new manufacturing areas of northern England. Draining the fens helped contribute to the success of the industrial revolution.
The Great Ouse protection scheme built on the work of John Rennie and other engineers. Draining water caused by rainfall from 13 English counties, the programme protects homes and farmland.
How the work was done
In 1799 local government officials in Lincolnshire asked engineer John Rennie for advice on dealing with waterlogged lands around the river Witham.
Rennie, whose work included docks, bridges and harbours, recommended that the river should be straightened and made deeper between the village of Chapel Hill and the town of Lincoln. He also suggested replacing some of the locks.
A later version of Rennie's plan included a series of large drainage ditches – effectively canals – that formed a part of the system now known as the Witham navigable drains. The scheme keeps an area of around 97 square miles (250 km2) from flooding.
The Great Ouse flood protection scheme saw engineers build a 10.75 mile (17.3km) long 'relief channel' running closely parallel to the river. The channel stores diverted flood water.
Engineers also constructed a 'cut-off channel' to control flood levels around the Great Ouse. The 27.75 mile (44.7km) long channel intercepts and diverts flood waters from the rivers Lark, Little Ouse and Wissey before they enter the fens.
Versions of both the relief and cut-off channels had been proposed by John Rennie in 1810.