A jack up vessel has been based in River Deben collecting riverbed samples ahead of East Anglia ONE offshore wind farm construction.
The materials would be used to analyse the type of bedrock and soil composition, according to Ipswich Star.
The next phase of survey activity will include digging trenches along parts of the proposed cable route at Martlesham Creek.
Charlie Jordan, project director of East Anglia ONE, said: “The work currently being undertaken on the River Deben and at Martlesham Creek is critical as it will determine the placement of the cable taking the electricity generated by East Anglia ONE on to the Bramford substation, where it joins the National Grid.
“In all our survey work, whether offshore, nearshore or archaeological surveys along the cable route, our intention is to always return the environment to its original state and mitigate the impacts of the works we are undertaking.“
Solely developed by ScottishPower Renewables, East Anglia ONE project received a development consent from Secretary of State on 17 June 2014.