Rapid population growth over the last 50 years coupled with large scale industrial development has led to major pollution problems in Lake Dianchi. This development has also resulted in significant sediment accretion in Lake Dianchi due to extensive deforestation of the lake catchment area. Further, up until the 1990's all wastewater and other runoff from Kunming and surrounding areas was pumped directly into the lake untreated. There are also large volumes of contaminated sediments in the lake bed. Consequently, the lake water is now undrinkable and is also rated unfit for agricultural and industrial use.