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With the rapid economic development and population growth, water shortages and deteriorating water environment is increasingly becoming the two major problems facing humanity. Fracture-karst water in many cities in northern China as a source of water supply in order to meet the water supply needs of the growing population, some cities over-exploitation of groundwater, leading to falling water tables, the formation of regional cone of depression caused by ground subsidence, depletion of ground Seisensui, saltwater intrusion, and deterioration of groundwater quality and a series of environmental and geological problems; while on the other hand, the rapid economic development has brought the accelerating process of urbanization, to expand outside the city, the massive construction projects in the construction of impervious area increases every year, many cities facing severe water shortages stormwater runoff is draining away and cause waste of water resources, at the same time, the formation of a large number of hardened ground rainwater can not naturally infiltration and runoff, through the drainage system can not be discharged as soon as possible, causing road water problems, and may even cause floods, to the community, the city harm the environment and people's lives and life. Therefore, the use of urban rainwater recharge of groundwater not only to supplement the the increasingly plaque lack of groundwater resources, improve the groundwater level to prevent or mitigate land subsidence, keep drinking water supply and spring protection, while rain through the shunt part to reduce the pressure of urban drainage network The probability of occurrence of floods in the investment and operating costs, reduce rainstorm. However, due to the combined effects of urban environmental pollution and the Department of the surface material, and other factors, urban stormwater by a large degree of pollution, the stormwater runoff directly recharge the underground will inevitably contaminated groundwater sources. Therefore, how to control stormwater runoff pollutants rainwater artificial recharge of groundwater technology in the most critical problem. Compared to road runoff, roof rainwater collection natural set of flow field and roof runoff water quality is better, the use of a large value; Jinan Karstic aquifer permeability coefficient is characterized by rapid infiltration of flood season rain conditions, beneficial rain artificial recharge of groundwater. In this paper, the the Jinan roof runoff water quality characteristics and influencing factors for the above-mentioned problems and advantages, the rainwater runoff pollution, rainwater, the abandoned stream as well as disposable flow value determination, explore economically and technically feasible approach for roof rainwater runoff study, the dynamic changes of the flood season back irrigation groundwater chemistry, groundwater recharge projects for the next stage of implementing and back irrigation provides the basic data and scientific basis for the control of fracture-karst aquifer water quality impacts and risks. The results show that: 1, the flood season roofing stormwater runoff pollutants color, turbidity, NH 3 -N, NO 2 -N, volatile phenol and SS, the main source of dust fall on the roof, fossil fuel combustion and vehicle exhaust; roof rainwater runoff water is rainfall duration, rainfall intensity and rainfall, seasonal factors. 2, by the cumulative pollution load of pollutants accumulated runoff study found that the presence of a first flush effect of rainfall on the roof, rainwater runoff pollution is serious; pollutant control purposes, taking into account according to the the roof rainwater water quality variation and follow-up to deal with the economy and security of the process to determine before the 6mm the early rain abandoned stream. Filtered through sand filtration system and sand filtration - activated carbon systems test, two filtration systems on the roof runoff pollutants purification, and compared with the groundwater environment quality class III standards, the results show that: the sand filtration system for runoff pollution matter in turbidity, color, suspended solids and metal ions better removal effect, but less ammonia and nitrite nitrogen removal; better sand filtration - activated carbon filtration systems on ammonia removal Groundwater Environmental Quality Class III standard provisions still can not reach ammonia, nitrite nitrogen removal less effective. 4,2010 annual flood season to recharge venues precipitation, water level, water temperature, pH value, conductivity, TDS, turbidity and salinity monitoring under rainfall groundwater chemistry dynamic response characteristics of rainfall Learn more about the dynamic variation of fracture-karst aquifer water chemistry and water - rock interaction mechanism.
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