There are other advantages of Tidal Lagoons. The walls of tidal lagoons
could support wind turbines, and the lagoons themselves fish farming. On
the East Coast of England they could also act as barriers to coastal
erosion, and this has been proposed to local councils in that area.

Construction in many cases could be using the "Mulberry" technique as
deployed on the Normandy Coast in 1944 to construct harbours.

regards
Ferrand, see www.grunweb.org.uk/page25.html