A large amount of the water diverted for irrigated agriculture seeps from earthen canals during its conveyance to fields. Besides a shortfall in water availability, a variety of environmental and economic damages are caused by canal seepage. Polymer sealants provide an economical alternative to permanent liners for reducing seepage from earthen canals temporarily. Field studies of the polymer sealant linear anionic polyacrylamide (LAPAM) conducted on two canals in Colorado, USA, and on a canal in Sindh, Pakistan, reveal the potential usefulness of LAPAM to substantially lower seepage losses. LAPAM application rates for the three experiments on the canals in Colorado were 14.2, 18.3, and 12.1 kg per ha of canal wetted perimeter area, and was 12.4 kg/ha for the canal in Pakistan. Flowing water balance tests show a decline of 69–100% in seepage rates for a period of up to three months after LAPAM application. Uncertainty analysis of the pre- and post-application tests on the Colorado canals indicates an 85% likelihood that seepage reduction of some magnitude occurred. Guidelines are presented for conducting further studies of LAPAM and other polymer sealants to systematically determine the impact of several factors that influence seepage control effectiveness.

用于灌溉农业的大量水在输送到田间时从土渠中渗出。除了水的短缺之外，渠道的渗漏还会造成各种环境和经济损失。聚合物密封剂为永久性衬砌提供了一种经济的替代方案，可暂时减少土渠的渗漏。在美国科罗拉多州的两条运河和巴基斯坦信德省的一条运河上进行的聚合物密封剂线性阴离子聚丙烯酰胺（LAPAM）的现场研究表明，LAPAM可以显着降低渗漏损失。在科罗拉多州的运河上，这三个实验的LAPAM施用量分别为每公顷运河湿润周界面积14.2、18.3和12.1 kg，而巴基斯坦的运河为每公顷12.4 kg / ha。流动水平衡测试表明，在使用LAPAM后的三个月内，渗漏率下降了69-100％。对科罗拉多河道施工前和施工后测试的不确定性分析表明，发生一定程度的渗漏减少的可能性为85％。给出了进行LAPAM和其他聚合物密封胶的进一步研究的指南，以系统地确定影响渗透控制有效性的几个因素的影响。