VINCI Construction UK will drain the lake to dredge silt build-up, creating an improved environment for aquatic life and deeper water for boating. The silt will be treated and used around the lake to grow reed beds for wildlife habitat and in other areas of the park to create wild flower meadows.
Wider regeneration plans in the park include the revival of the old lido, a cafe, a boating jetty, pedestrian paths and a car park.
Work on the lake is expected to be completed by early summer, with the whole park renovation scheduled to be finished by the end of the year.
London Borough of Barking & Dagenham councillor Bert Collins said draining the lake would bring massive benefits to wildlife.