The Longshou II Dam, also referred to as Longshou No. 2, is a concrete-face rock-fill dam on the Heihe River, located 35 km (22 mi) southwest of Zhangye

Zhangye

-Administration:Zhangye has 1 urban district, 4 counties, 1 autonomous county, 97 towns, and 977 villages.-Demographics:Zhangye has a total population of 1,260,000, only 260,000 being urban residents...

 in Gansu Province, China. It is part of the Gansu Heihe Rural Hydropower Development and supports a 157 MW power station. The dam's first feasibility study was carried out in 2000 and river diversion construction began in December 2001. In June 2002, the river was diverted and in September that year, filling of the dam's body began. On 17 August 2004, the first generator was operational with the rest by the end of the year. The 146.5 m (481 ft) high dam withholds a reservoir with a capacity of 86200000 cubic metre. It's spillway

Spillway

A spillway is a structure used to provide the controlled release of flows from a dam or levee into a downstream area, typically being the river that was dammed. In the UK they may be known as overflow channels. Spillways release floods so that the water does not overtop and damage or even destroy...

 is located on the right bank and is a controlled chute type with a discharge capacity of 2696 m3/s. Water is delivered to the dam's power station downstream via a 1.7 km (1 mi) long tunnel. The dam is located upstream of the Longshou I Dam, an 80 m (262 ft) tall double-curvature arch dam

Arch dam

An arch dam is a type of dam that is curved and commonly built with concrete. The arch dam is a structure that is designed to curve upstream so that the force of the water against it, known as hydrostatic pressure, presses against the arch, compressing and strengthening the structure as it pushes...

 with an installed capacity of 52 MW.
Upstream is the Xiaogushan Dam, a gravity dam which diverts water to a 102 MW power station.