Storm water modeling solution is needed.

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I am working in a small watershed project where the vegetation coverage has gone tremendously down in thelast 5 years. Some other factors have also contributed towards increased volume of runoff, which enters streams at a considerablyfaster rate.

In our watershed we have a severe problem of flood risk and erosion. We want to construct Infiltration basins to manage this storm water. The main goal is to manage water quantity in addition to protecting water quality withoutmajor soil erosion happening.

We need to choose a best storm water model for this purpose. We have some data limitations like, we don't have daily rainfall and temperature data for the area. So we don't know how to fill these information gaps while using the SWM. It will be great if you can suggest us some storm water modeling options with lesscomplex inputsor a solution about how to work with this particular data limitation.

Other data like soil type, slope, area, % of vegetation coverage, vegetation type is available

5 Answers

  1. Thanks Yoshimi for the information, and thanks water development team for bringing this information to my knowledge.

  2. Here is another perspective by Steven Trinkaus, from the US, and the world leader in Low Impact Technology. @ Kae Man Man, My name is Steve Trinkaus. I am an engineer in Connecticut (US). I am doing some consulting for Pusan National University and Land & Housing Institute on Low Impact Development in South Korea. I have made several presentation on LID in South Korea over the past year and will be returning to South Korea in October 2014 to present at the IWA conference. Maybe we can meet up at that time. Regarding your particular problem, Hydrocad is a much simply hydrology program to model the watershed with the appropriate soil type and vegetative cover which will give you peak rate and runoff volume for the desired design storm events. It does not require rainfall data, temperature data to run. You simply need to know the design rainfall amount for each design storm. As an example, when I live the 2-yr rainfall event is 3.3” per 24 hours. The time of concentration is based upon the land cover and slope of the land and is comprised of several components: overland flow, shallow concentrated flow, open channel flow, and pipe flow. If you would like to discuss further, please contact directly at strinkaus@earthlink.net. Hope to hear from you. Best Regards, Steve

  3. @Kae Man one of the simpler storm-water models for this purpose (runoff and infiltration basin design) is the US EPA SWMM. You should be able to find a recent version online via Google. However, you do need some rainfall from some source as input. In the US, we have many estimates from our weather service of the 100-year (1% annual likelihood) rainfall, as well as other frequencies of interest, that we use for estimate storm event inputs to SWMM. Even if you just have a storm rainfall total, and some idea of how it was distributed in time (convective, stratiform, mixed event), you can make reasonable estimates of runoff and basin design in SWMM.

  4. Maybe visual / photo also helpful for some to actually see the site, since your description seems rather general (not quantitative), and not so much data for any engineers to give any thoughts or advice.