拦网防止钉螺扩散的方法存在着网孔易很快被河流中的漂浮物堆积，影响河渠的泄流能力，需经常清理或更换的缺点，给实际工程中的管理运行造成了不便。针对此问题，提出改进拦网通过网箱截螺的方法。通过模型试验研究，对比急流、缓流水流条件下的网箱对钉螺载体的拦截效果，研究发现网箱拦网式截螺法具有较好的拦截钉螺载体效果，既有防止钉螺扩散的作用，同时又有“堵而不死”的特点，不会堵塞河渠，使河渠基本上保持畅通。初步验证了该方法的可行性。

A network preventing oncomelania diffusion is easily blocked by floating materials in a river to reduce the discharge capactity. Therefor, the network needs to be often cleaned and replaced, which causes the inconvenience to the operation management of practical engineering. Placing the network net cage intercepting oncomelania can solve the abovementioned problem. On the basis of model test, the intercepting oncomelania effects of netcasge are compared under the condition of both ina rapid follow and slow flow. The study results show that the net casge intercepting oncomelania has a better effect to prevent snail diffusion, and the channel dont be clogged to let the flow smoothly. The feasibility of the net cage intercepting sail is preliminarily tested.