pineferous wood-lined, boggy ravine. It is part of a Site of Special Scientific Interest (SSSI) because of its populations of Dartford warbler, nightjar and woodlark, and is a nationally important habitat for dragonfly and damselfly. The stream then flows through the grounds of the Royal Military Academy Sandhurst, entering Bathing Pool, and then passing through a series of engineered ponds and weirs, which create a significant obstacle to the movement of fish, to reach the Lower Lake. This is also supplied with water from the Upper Lake, to the south of the stream. There is a large control structure at the outlet of the Lower Lake, impassable to fish, and then a series of high weirs of that status. Below the grounds of the Academy, the stream flows in a culvert under a car park for a retail outlet, and several more culverts under roads to reach the Blackwater. The confluence used to be the point at the three-county tripoint, but when the Blackwater Valley road was built in 1990, the stream was moved slightly north, for the roundabout that links the A30, A321 and A331 roads. The river then flows through Shepherd Meadows, an SSSI noted for the Black Poplar tree, and a variety of wild flowers, including sneezewort, knapweed, betony, meadowsweet and great burnet. As the river curves to the west, it passes under the North Downs Line railway bridge, flows past Sandhurst sewage treatment works on the right bank and enters Trilakes Country Park. Former gravel pits flank the river on both sides, and as it passes the village of Finchampstead, the channel is briefly called Long Water. Soon it reaches New Mill, where there is a weir and sluice. The mill was a corn mill in 1871 and produced animal feed until the 1950s, when the building was sold. The watermill and mill house are grade II listed, with parts of the buildings dating from the 15th century. They were subsequently used as a restaurant, with the restored mill wheel, gears and machinery visible from the seating area, encased behind glass screens. The river follows the northern edge of Bramshill Plantation, of woodland managed by the Forestry Commission. It is a Special Protection Area in view of the number of bird species to be found there, and also has large populations of damselflies, dragonflies and silver studded blue butterflies. Notable flora includes marsh clubmoss and pillwort.