Design methods of sponge greenway in urban shallow mountainous area in northern China: taking the greenway of Luquan District in Shijiazhuang as an example

The annual rainfall in North China is less than normal and the rainfall is concentrated. Rainstorms frequently occurs and the annual evaporation is large, which cause serious flood and water shortage problems. The rainstorms in the windward area of the piedmont area constitute a threat of flood to the plain area. Building greenway in urban shallow mountainous area is of great significance to alleviate flood and rain disasters. With the aim of solving the problems of the water resource shortage in northern China and rainwater management problems in urban shallow mountainous areas, firstly, this paper discusses the necessity of sponge greenway's construction by analyzing the climatic characteristics of northern China and characteristics of rain and flood disasters in urban shallow mountainous area. On this basis, combined with the greenway project of Luquan District in Shijiazhuang, Hebei Province of northern China, the paper proposes design methods for spongy greenway. The design strategies of sponge greenway consider three following dimensions: 1) taking urban mountainous areas of northern China as the natural substrates; 2) taking greenway as the runoff buffer; 3) integrating the LID facilities into greenway design. This study considers the design strategies based on two perspectives of rainwater safety and utilization. Finally, this paper uses the storm water management model (SWMM) to quantify the control effect of LID facilities on stormwater runoff, and compares the storage efficiency of sponge greenway with the traditional one. The results show that the sponge greenway has better efficiency in controlling total runoff, peak flow and delaying peak time. Spongy greenway can effectively solve the problems of rainwater regulation.