The schemes on the River Blackwater at Bocking have been designed to reduce erosion and flood risk, improve fish habitat and the overall ecology of the river.
The first project, led by the Environment Agency, began in April 2014, and work was carried out over a 2 week period in March 2015.
The latest scheme, taking place further downstream by the Bocking nature reserve and designed by the Essex Wildlife Trust (with Defra funding), started last week and is set to be completed within 3 weeks.
The river has been heavily modified in the past to improve land drainage and reduce flood risk, however this created a number of problems, which affected the fish habitat.
Among the changes introduced by the projects were: