Impact of different low impact developmental combinations on water quality and quantity and cost-benefit analysis
- Article
- Figures
- Metrics
- Preview PDF
- Reference
- Related
- Cited by
- Materials
Abstract:
With the rapid development of urbanization,the impervious surface of cities and towns significantly increases,which causes the change of hydrological process and the increase of flood events.Due to the special construction properties of industrial parks,the impervious area is much larger than previous area,so it is easy to cause waterlogging disasters and runoff pollution in the industrial zone.Low impact development (LID) facilities can effectively alleviate urban waterlogging and improve the urban water ecological environment. Impact of different LID combinations on rainwater source control and pollution load reduction,taking an industrial park in Huainan City as the research object.Five LID combination schemes were constructed by the SWMM model.In different return periods,the water quantity and quality of five schemes were simulated,and the reduction effects of different schemes on runoff volume,runoff coefficient,peak discharge,and pollutant concentration were analyzed.Methods of the life cycle cost and the benefit monetization were used to calculate and monetize the economic benefits of every kind of LID combination scheme,and the return on investment also was compared to the five different schemes to select the most appropriate LID combination scheme. The results show that the combination of green roofs,rainwater tanks,rainwater gardens,and permeable pavements has the best reduction effect on runoff and pollutants concentration,and the combination of green roofs,rainwater tanks,vegetative swales,and permeable pavements has the best reduction effect on peak flow.The combination of rainwater tanks,rainwater gardens,and permeable pavements has the highest investment return based on cost-benefit analysis.Different LID schemes have a certain reduction effect on water quality and quantity,however,the reduction effect decreases to different degrees with rainfall return period increase.Different LID schemes all have a considerable return on investment,but the addition of green roofs reduces the return on investment of the combination,resulting in the low return on investment for the combination with green roofs. Adding LID facilities has a significant reduction effect on runoff and flood peaks in the study area.Even if the simplest rainwater tanks and vegetative swales are added,the reduction rate of runoff can reach about 11% and one of flood peak discharge can reach about 30%.However,with the increase of rainfall return period,the reduction rate decreases,so more LID facilities need to be added.Vegetative swales have a better effect on reducing peak discharge,and rainwater gardens have a more obvious effect on runoff reduction.Although the addition of green roofs can reduce more runoff and peak flow,the effect of the rainfall return period is more obvious.While the rainfall return period increases,the reduction rate of peak flow decreases to a certain extent.Life cycle cost analysis and benefit monetization analysis show that rainwater gardens can well improve the rate of return on investment,and green roofs have a certain effect on the reduction of runoff and pollutants,but the high investment cost and maintenance cost of green roofs lead to a low rate of return on investment.The combination scheme of green roofs,rainwater tanks,rainwater gardens,and permeable pavements has the highest comprehensive benefit and is more suitable for the planning and construction of industrial parks.
Keywords:
Project Supported:
Clc Number:
Mobile website
