Effectiveness of soil and water conservation associated with a natural gas pipeline construction project inChina

Abstract

AbstractA natural gas pipeline extends over a distance of 310 km in the Hebei Province of China and passes through various zones of natural vegetation, mostly wooded. Construction required a working width of about 40 m and a 1.4‐m‐wide trench to be dug to a depth of 2.4 m to enable the installation of a pipe with a diameter of 1,016 mm. The construction process had to manage an irregular configuration of terrain with steep slopes, varying degrees of instability, and a propensity for erosion and land degradation. To prevent potentially massive soil erosion and further deterioration of the affected environment, a comprehensive soil and water conservation plan was designed and implemented. A 3.25‐km‐long study area was selected in rugged hilly country and was divided into seven topographic zones, with slopes ranging from <10° to over 50°. Different soil and water conservation measures were adopted in each zone, including engineering measures, revegetation measures, and maintenance measures. One year after installation, trees planted in individual holes grew well in each zone and the vegetation cover on the slopes treated by hydroseeding exceeded 90%. In addition, run‐off and sediment yield on slopes were significantly reduced. These conservation measures were conducive to environmentally sustainable development and may serve as a scientific reference for ecological restoration and vegetation reconstruction in future pipeline construction projects in similar terrain. Furthermore, these measures also helped to ensure the safe operation of the pipeline and provided protection for people living and working along the pipeline route.