The area around the Holland Park roundabout was submerged by up to 3ft 2in (1m) at about 03:55 GMT.
Storm Goretti is causing flooding, power cuts and strong winds across parts of Sussex and Kent.
Pittsburgh Water cut its budget for stormwater improvements, stalling projects for flood control across the city.
The Lincoln County Health Department says the boil order could stretch three more weeks, forcing Libby businesses to rely on bottled water.
Fire services have issued a warning to Wiltshire drivers, after attending two incidents involving stuck vehicles.