The lakes in west Jiangsu Province have mostly high levels of nutrients, causing eutrophication. Lake Xuanwu is the most eutrophic, while Lake Baima is the least. Some lakes have water quality worse than national standards. Only Lake Luoma and Lake Xuanwu are improving, with decreasing nitrogen and phosphorus levels. Other lakes are getting worse, with increasing nutrient concentrations. Different lakes have different causes for their water quality changes, like pollution from rivers and agriculture. Lakes with low water flow have higher nutrient levels compared to lakes with high water flow.