A flood warning, meaning flooding is expected, immediate action required, has been issued by the Environment Agency for properties near Ruskington Beck in Ruskington.
Heavy rainfall has fallen overnight and more is forecast and the river is expected to continue to rise.
Low lying land will be affected first.
The flood warning issue was issued at lunchtime today, Wednesday March 9.
The Environment Agency advises anyone wanting more information call Floodline on 0345 988 1188, select option 1 and enter Quickdial number 0313355.