Its drained land, the Don was straightened to avoid Fishlake,Snaith and Sykehouse flooding built in the 1600's so has not been flooded to any degree in hundreds of years. The whole drainage created the Isle of Axholme, which is good arable land.Although I have sympathy for the people in Fishlake do people really buy houses without looking at a map and checking contours, rivers etc? They probably check for broadband coverage and proximity of a reasonable school but seem to forget the essentials. Maybe they think that if it was deemed ok to build houses there then it MUST be ok.
Maybe not possible but it would be good to talk to the guys who did all the groundworks before buying new houses.