An Experimental Study on Concrete and Geomembrane Lining Effects on Canal Seepage in Arid Agricultural Areas

Abstract

Canal lining is commonly used to reduce seepage loss and increase water use efficiency. However, few studies have quantitatively estimated the seepage control effects of different lining materials under different service times. Ponding tests were conducted on the same canal section with four different lining statuses to investigate the canal lining effect on seepage control and its impact factors in arid areas. The cracks and holes in different lining materials were surveyed, and the canal seepage rates under the four test treatments were calculated by monitoring the water level change in the canal. The results show that the cracks in the joints of the two precast concrete slabs and holes in the geomembrane, which are located 0.25 m above the canal bottom on two sides of the canal, are responsible for the increased seepage loss. The new concrete and geomembrane lining combination reduces seepage by 86% compared with no lining, while seepage can be reduced by 68% using the concrete and geomembrane lining combination after three service years, and the amount decreases to 11% by using geomembrane lining with a three year service time. Based on the experiment and literature, a statistical relationship between the seepage reduction and lining service time was established, which provided a possible and easy way to estimate seepage losses from lined canals and improve the estimation accuracy using an empirical formula. Without considering the service time lining effect, the seepage loss is underestimated by 58%, and the canal water use efficiency is overestimated.

Net present value (NPV) of the rehabilitated irrigation channels to increase agricultural production

“…The water losses calculated for the irrigation operations include those at the tertiary, secondary, and primary levels. The amount in each of these is, however, influenced by the length of the channel, the surface area of the track, the wet circumference of the channel, and the groundwater position [8]. It is important to note that efficient irrigation management focuses on providing suitable irrigation practices for plant cultivation with the water discharged on agricultural lands guaranteeing the proper growth of crops.…”

“…Where B is the loss of water during distribution, inflow discharge is the amount of water entering, and outflow discharge is the amount of water coming out. The efficiency is, therefore, calculated using the following equation [8],…”

“…Moreover, those constructed with bricks were observed to have lesser efficiency than concrete. Therefore, concrete is recommended to ensure the amount of water channelled to the rice fields does not decrease [8].…”

Analysis of Conveyance Losses from Tertiary Irrigation Network

“…Earthen irrigation channels are usually made through loose soil formations, since irrigation channels convey water to farmers' fields over large distances; in the process a significant amount of irrigation water is lost [1,2]. Such losses are technically termed as conveyance or operational losses and are mainly caused due to seepage into soil or evaporation.…”

Research on the Comprehensive Optimization of the Hydraulic Performance and Frost-Heaving Resistance of a Parabolic Channel

“…A concrete lining is a kind of anti-seepage channel and water-saving engineering measure that is widely used in China's irrigation district [1][2][3]. In seasonally frozen areas such as Inner Mongolia and northeast China, however, the base soil of a channel expands due to the icing of soil water, which squeezes the concrete lining structure layer and causes the lining plate to become damaged by bulging, cracking, uplifting, and even collapsing [4].…”