CEH Digital River Network of Great Britain
收藏资源简介:
This is a view service of the CEH 1:50k rivers dataset. This is a river centreline network, based originally on OS 1:50,000 mapping. There are four layer: rivers; canals; surface pipes (man-made channels such as aqueducts and leats) and miscellaneous channels (including estuary and lake centre-lines and some underground channels). The dataset was produced within a long-term project of the Institute of Hydrology (now CEH) between the mid-1970s and the late 1990s. The project digitised, (either manually or using 'laser scanners') the "blue line" layer of the Ordnance Survey's 1:50,000 2nd series (Landranger) maps. The dataset consists of all the single blue lines from the source maps, plus centre-lines from double sided rivers, lakes and estuaries. All gaps in the source material have been closed, using local knowledge where necessary, to give a river network that is continuous from source to mouth



