三峡工程二期上、下游横向围堰与混凝上纵向围堰共同形成二期基坑，测绘工作要求很高。为此，配置了两台多功能全站仪，可自动记录观测数据、计算三维坐标和预置放样数据；还配有DIOR3002无反射棱镜测距仪、激光准直经纬仪等先进测绘仪器，实施了TCA1100电子全站自动化测量、GPS实时差分自动化测量等先进测绘技术，可有效地进行水下测绘工作。 The Three Gorges Project Phase II, the downstream transverse cofferdam and the vertical cofferdam co-formation of the second phase of the pit, surveying and mapping work requires a high. To this end, the configuration of two multi-function total station can automatically record the observed data, calculate the three-dimensional coordinates and preset loft data; also equipped with DIOR3002 non-reflective prism rangefinder, laser alignment theodolite and other advanced mapping equipment, implemented TCA1100 electronic total station automation measurement, GPS real-time differential automatic measurement and other advanced surveying and mapping technology, can effectively carry out underwater surveying and mapping work.