我县通南高沙土地区水土流失、河坡坍塌情况较为严重。其原因,除了植物措施较差以外,在工程方面一个重要的原因是,缺少面广量大的控制建筑物。已建造的一些排水涵洞一般也存在渗漏、冲刷、洞身不均匀沉陷,危及建筑物安全。1977年以来,我们设计了内径30～100厘米的进口落井消能排水涵洞,主要用于中、小沟头防护。目前已建数百座,凡按设计标准施工的项目,都安全可靠,排水情况良好。 Soil and water loss in the high sand area of ​​Tongnan in our county has caused more severe river collapse. The reason for this is that in addition to the poor plant practices, an important factor in engineering is the lack of extensive control buildings. Some drainage culverts that have been constructed generally also have leakage, erosion, uneven cave settlement and endanger the safety of buildings. Since 1977, we have designed the imported drop well energy dissipation culvert with an inner diameter of 30 to 100 cm, which is mainly used for medium and small head protection. Hundreds of buildings have been built so far, and those constructed according to design standards are safe and reliable, and drainage is in good condition.