Generally, when the installation of PVC lay flat hose is checked and accepted, the water test will be carried out. So, what is the process of water test? In other words, how does it test water? Generally, the main process of its water test includes the following steps: first, the installation of PVC lay flat hose is completed, the first qualified test can be carried out, first, the control gate valve is opened, the whole pipeline is washed with edema, the residual debris is removed from the PVC lay flat hose, and then the tail of all levels of PVC lay flat hose pipeline is blocked with a plug. Secondly, according to the corresponding pressure of water supply, adjust the gate valves, check whether the joints and pipes are leaking, whether the drip head is uniform, whether the various instruments are sensitive, etc. If there is a fault, it should be discharged in time. Attention should be paid to the backfilling of PVC lay flat hose pipeline after the water test of agricultural PVC lay flat hose is normal. Backfilling should be carried out in layers. Fine sand must be used to close the pipeline and tamping should be done at the same time to prevent uneven stress of the pipeline. In winter construction, PVC lay flat hose pipes are backfilled in the afternoon to reduce the influence of thermal expansion and contraction on the linear variation of pipes.