Research On Local Utilization Of Rainwater Collected From Urban Road

Utilization of urban road rainwater is being concerned more and more, at present, the methods ofurban road rainwater utilization is short, the utilization efficiency is low in our country. The paperlearn from the advanced experience of other countries and propose a scheme using local rainwateraccording to the characteristics of urban road rainwater quality and the situation of road rainwaterutilization in our country. Carry out a simulated test for the scheme and then make a further analysisabout its efficiency. The results are as follows:1. The scheme is: Set up sedimentation tanks and reservoir for collecting road rainwater on theroadside, reservoir connect the pervious hose layed under the soil and surround the roots of the tree.The rainwater on the road inflow to the reservoir, to the pervious hose and then infiltrate to the soil, itcan be absorbed by the tree, increase the soil moisture, supplement the ground water and then realizethe utilization of urban road rainwater in the same spot. The troditional roadside collectting wellcollect the rainwater and discharge into ueban drainage system, the rainwater resources is notadequately utsed and it will increase the pressure of drainage pipe network and wastewater treatment.2. Carry out the simulated test on the collection efficiency of road rainwater. Threshold rainfall ofthe horizontal concrete pavement without antecedent rainfall is 1.5mm, the collection efficiency ofroad runoff increase with the increasing of rainfall amount; the average collection efficiency ofhorizontal surface is 75.20%. The harvesting surface with bigger transverse slope will have moreability of collecting rainwater. The ability of collecting rainwater of upper harvesting surface withongitudinal slope is bad and its utilization efficiency is low, a large number of reainwater run to thedownstream and increase the difficulty of the rainwater utilization, should add some more collectionports in the downstream for collecting rainwater timely.3. Carry out the simulated test on the infiltration characteristics of pervious hose. The pervioushose can keep a high infiltration speed at the begaining of irrigation, the infiltration speed decreasegradually until the water infiltrated completely. The water more distributed in the vertical direction inthe soil. The pervious hose that have bigger speed and amount of irrigation will have more soilwetting front and soil moisture. The infiltration speed in the sand is bigger than soil; the infiltrationtime need in sand is much less than soil at the same level of irrigation amount.4. The scheme reaches the largest utilization efficiency at the situation that rainfall has smallintensity and long time. In the rainfall that has large intensity and time, the utilization efficiency is nothigh, should increase the length of pervious hose and lay some sand around to inhance the utilizationefficiency.