On the outbreak of World War II, parts of the finished but uncommissioned Central Line eastern extension were used as public air-raid shelters. Immediately north of Stratford station the westbound tunnel was taken over by West Ham Corporation.
The shelter capacity was 2,136 and access was from the west end of William Street. Initially, toilets were only installed near the tunnel entrance which led some shelterers to use those provided by the adjacent Leyton Council shelter instead.