Depending on your data availability and access to a computer with decent computing power you can easily do a hydrological assessment of your basin. First off you would need a pretty good Digital Elevation Model (DEM) with relative good resolution, depending on the size of your watershed 15-30 meter resolution can be a good first try. If you have access to ArcGIS the Arc-hydro extension would be a good first step in looking at flow paths and modeling the catchment. For flooding analysis, you can use an US Army Corp of Engineer developed independant (as in it doesn't need ArcGIS) freeware package called HEC-RMS and/or HEC-RAS. 

There are other GIS tools out there that could probably do the samething these software package can do so don't limit your self to these software. 

Hope this helps.

Thank you Paul, Thank You Michael,

The DEM I am looking forward to use is SRTM DEM. In my masters I have used Vflo a distributed hydrological model for flood inundation mapping. The problem with vflo is it could generate a hydrograph but the inundation map could not be obtained.

Please suggest a model which would do both the work.

Regards

Salim Khan

Hi Abdullah

What kinds of flooding are you trying to assess? Is flooding driven by a natural climate regime with seasonal or monsoonal rainfall, or is it the result of some alteration of river flows e.g., a dam up- or downstream? It is a relatively easy thing to map flood extent using remote sensing - we have found MODIS very useful to do this. This would provide you with some quantitative data on historic flooding in your wetland; you can then do a regession model against river/channel flows. Although this is crude, it can give reasonable results, and at least a starting point...

Its basically the result of rainfall in the downstream regions. I am trying to predict the impact of flooding on the ecology of the Wetland.

I will send the abstract of my work if you would kindly tender your help.

Hi Abdullah

It would be good to have a look at the abstract. It sounds similar to work that we have been doing here in the Okavango, where we linked a semi-distributed hydrological model to species-distribution models of wetland plants to try to assess effects of upstream hydrological and climate change on wetland vegetation. I've attached an early paper, but can send more if you like.

Cheers

Mike

Hello Abdullah,

we have used a hybrid approach to study inundation patterns in Mekong and Brahmaputra basin in South East and South Asia. U can browse from the link.

http://www.worldfishcenter.org/resource_centre/CBFC/4_Nagabhatla_landscape%20report.pdf

Part of the work is published at: ::http://www.tandfonline.com/doi/abs/10.1080/15715124.2012.664551#.VC_ZD_mSwdo

( I can post u the script incase u find the work related to what you are intending )

Please post the Script.

Hi Abdullah

I've attached a paper linking flood extent (intepreted from MODIS) to floodplain plant species composition, and another which looks more carefully at which components of "hydroperiod" affect which plant communities most. We are currently working on a third which details the development of plant species distribution models (using CCA) and their application to assessment of change due to upstream land use change and climate change. This third one is still in draft form, but as soon as we get it closer to submission I'll send you a copy.

I have also attached a paper by my colleagues describing the hybrid reservoir-semi-distributed model which we use to drive the vegetation models.

Hope this helps - in the meantime, I'll have a look at your abstract.

Cheers

Mike

Hi Abdullah - you might also find this poster useful - it describes 3 different approaches to modelling the effects of hydrological change on floodplain ecosystems.

Thank you Mike. I am a new researcher in this field. I shall be glad if you could kindly send some materials for the beginners in this area of research.

Hi Abdullah

Could you send me approximate geographic coordinates for where on the Barak river the Sonbeel wetland is? I would like to have a look on Google Earth.

Thanks

Mike

Its already there on the abstract i had sent.  The map of the study area is given along with co-ordinates. please check it and let me know if you got it there.

Hi Abdullah - yup, sorry I hadn't got that far down - I see the map. I had thought it was just an abstract. I'll have a look...

Hi Abdullah

I suggest the following approach (though there may other better ones!):

1. The river basin seems well-suited to a modelling exercise: well-defined catchment boundaries, well-contained outflows.

2. Important questions are:

a. How many rain gauges in the basin; localities, length of record?

b. How many river flow gauging points; localities, length of record?

c. What are the other major environmental variables: climate (temperature, relative humidity, potential evapotranspiration)?

3. Initial steps should be to construct a rainfall runoff model of the upstream catchment to drive river inflows to the wetland. You could use the Pitman approach (Hughes 2004; Hughes et al. 2006; Wilk et al. 2006), or some other rainfall-runoff model.

4. Next, to develop a time series of inundated area for the Sone Beel from MODIS or other remote sensing data –ideally with monthly extents.

5. Then, find a best fit model for (inflows + locally incident rainfall)-(outflows + evapotranspiration) against inundated area.

6. Then you will be able to test scenarios of changing rainfall patterns in the basin, or of changing wetland drainage infrastructure, and see effects on area of inundation.

You really need to get a competent river/wetland hydrologist on your team.

Some references:

Hughes D.A. (2004). Incorporating groundwater recharge and discharge functions into an existing monthly rainfall-runoff model. Hydrological Sciences Journal, 49, 311.

Hughes D.A., Andersson L., Wilk J. & Savenije H.H.G. (2006). Regional calibration of the Pitman model for the Okavango River. Journal of Hydrology: Water Resources in Regional Development: The Okavango River, 331, 30-42.

Wilk J., Kniveton D., Andersson L., Layberry R., Todd M.C., Hughes D., Ringrose S. & Vanderpost C. (2006). Estimating rainfall and water balance over the Okavango River Basin for hydrological applications. Journal of Hydrology: Water Resources in Regional Development: The Okavango River, 331, 18-29.