Construction Control Network Layout of South-to-North Water Diversion Middle Line

Based on the data of "First-Level Construction Control Network of First Phrase Project Main Line of South-to-North Water Diversion Middle Line（without the Beijing-to-Shijiazhuang section）",the 1/5000 topographic map provided by Water Conservancy Survey General Unit of Henan Province was made as control network layout plan map by this paper.By GPS control network optimization design,the Construction Control Network of South-to-North Water Diversion Middle Line Project was layouted,the survey data was processed and the precision was analyzed.