兰溪地处金华江、衢江、兰江3江之汇的特殊位置,下游受富春江水库回水顶托的影响,极易出现洪涝灾害。境内“三江”两岸防洪堤总长达168.7公里,受保护人口数十万。有集雨面积10平方公里以上的小流域达到34条,受影响人口20万,这些小流域多数源短流急,每年都发生过山洪、滑坡、泥石流等自然灾害。还有小(二)型以上水库133座,各类大小山塘1万余座,数量列全省前茅。 Lanxi is located in the special location of Jinhua River, Qujiang River and Lanjiang River 3 Rivers. Due to the influence of the backwater support of Fuchunjiang Reservoir in the downstream, Lanxi is prone to floods. The territory of the “Sanjiang” flood control embankment total length of 168.7 kilometers, hundreds of thousands of protected population. There are 34 small catchment areas with rain-collecting areas of more than 10 square kilometers and 200,000 affected people. Most of these small watersheds are in short supply, and natural disasters such as flash floods, landslides and landslides occur each year. There are small (two) type reservoirs 133, all kinds of size ponds more than 10,000 seats, the number of the forefront of the province.