Questions related to Watershed Hydrology
I would like have a discussion on the monitoring of river (water level/discharge) for early warning We would like to use non contact type of sensors in the Kosi basin of Bihar in India to understand the flow variability and impact on flood. I wanted to know the following
1) How to choose the site for deploying the sensors
2) How to select the sensor type for this
3) What are the criteria to decide the optimum number of the sensors in a watershed.
4) How to generate the cross section to evaluate the discharge.
5) In absence of historical data, how one can develop the model (Rainfall-Runoff)
6) What are the open source software to carry out hydrological model other than HEC-HMS
7) For developing the hydrological model, what the data set we required other than (DEM, LULC, Soil Map)
8) Any technical guide/paper to divide the sub watershed according to gauged sensor
9) How can we best use of dense network of AWS and ARG in that watershed.
10) Best tool to analyze the hydrograph
In first order watersheds, can the shape index (Ff=A/Lb²) and the elongation ratio (Er=(2/Lb)*(A/Pi^0.5) return values >= 1?
Working with large watersheds, these values tend to be < or = unity. However, working on small hydrographic basins (1st order) I find some volers above the unit.
Is there any convention that the values of Ff and Er cannot exceed unity?
Please share methodologies to quantify the hypothesis that the "reduced evaporation" and "increased transpiration" from tree cover area (forested region) results in increased water conservation.
Dear Researchers, Water Managers, Climate Experts, and Policymakers,
By understanding the ways in which ancient communities were successful at or failed in attaining sustainable water management, recent studies have attempted to provide important information for modern communities facing climate change impacts which are consequently resulting in water scarcity, security, safety, and sustainability issues. For example:
Conference Paper Study of Vandiyur Tank Cascade System in Madurai: Exploring ...
Can the perspective of re-implementing ancient and indigenous techniques of water management in contemporary conditions be considered as an imperative proposition to drafting modern water management policies? Your opinions, observations from your case studies, and evidence from your published work, if shared, will be gratefully appreciated.
Watershed development is the set of practices to impound the flowing rainwater, and thus help it percolate. But the groundwater recharge is also dependent on many other factors like the amount of rainfall, rainfall pattern, topographic slope, soil type, soil thickness, rock type etc. How do we measure the impact of watershed development on the groundwater?
Please do share publications on this topic.
I am studying mobility and socio-cultural interactions among palaeohistorical hunters-fishers-gatherers in the Laurentian part of the Subarctic. My main research hypothesis is that rivers and watersheds are "vectors" that had a structuring role on mobility and social interactions. Since I am interested in examples that has been documented around the world, can you recommend me ethnographies, archaeological publications or researchers that have studied watershed in order to understand cultural or sociological phenomena?
There's any software able to efficiently simulate snowmelt runoff paths on a specific surface (also looking at the geomorphology, e.g. considering available DEMs), starting from local snowmelt runoff measures?
>> More details: I have punctual values of snowmelt runoff (m3/s), crossing the end section of a watershed, but I would like to find out a solution so as to spatially simulate snowmelt runoff flows on the entire watershed, looking at the values obtained to its end section.
Because I see that to estimate soil loss throught USLE, RUSLE models, some researchers use models that are not compatible with the study region?
The check dams used as torrent control works have some characteristics - in my opinion - which are neither quite those of retention dams (hydraulic structures) nor quite those of retaining walls. So, taking into account their behavior over their period of existence (50 to 100 years), a short period the check dam works as a hydraulic structure subject of hydrostatic/hydrodynamic pressures. Then, after the upstream sector is completely filled with sediments, it works as retaining wall, perodically submited to floods. I put this question because, verifying such a structure using Eurocode 7 I obtain larger dimensions than using the old global factors of safety. And a more than 100 years of experience shows that economically the last approach is better.
According with the experience and technical regulations in the European countries, are them subject of Eurocode 7 or of some special regulations?
I am new to HEC HMS. and i am thinking to perform rainfall runoff modelling of a basin near my area using HEC HMS. The data i have is rainfall time series data and flow data of my outlet point. I want to estimate the discharge and compare the discharge obtained from the model to that of the real observed data..how can i perform the modelling without using soil data as i dont have any soil data or soil classification data of my region (for SCS CN method)?
Despite its importance in watershed hydrology and management, until now I know CN-model is a manually operated model. If there are some experiences I would like to hear from the group.
Our recent study base on delineating and establishing paired watershed in two different vegetation types in Sri Lankan rain forest. Please shire your experience with any countries or regions
A 10, 20 or 30 year period will just be fine. I have got some few maps showing some trends but I need figures to plot some graphs
The inflow prediction in the reservoir is a very important and challenging task for the reservoir operation. However, in a large basin, there are many sub-catchments. So initially, one needs to forecast inflow for individual sub-catchments and then sequentially progressing downstream to forecast inflow into reservoir. Which data driven or artificial intelligence technique will be more appropriate for such application?
The last version of TOPKAPI ( (TOPographic Kinematic APproximation and Integration) Distributed Hydrological Model, called TOPKAPI-eXtended or TOPKAPI-X, free software and open source.
MAIN MODIFICATIONS IN TOPKAPI - eXtended Model:
1.- Introduction of an 8-DIRECTIONS drainage network
2.- ADDITIONAL SOIL RESPONSE in order to reproduce different hydrological situations. Two soil layers
3.- Addition of an infiltration module based on the GREEN-AMPT MODEL, to reproduce hortonian processes
4.- Introduction of two coefficients to take into account the sun height with respect to the cell aspect for the RADIATION ASSESSMENT and ALBEDO
5.- Addition of a GROUNDWATER MODEL based on the cellular automa: full 2-D IFD (integrated finite difference) groundwater model
6.- Development a powerful graphical interface linked to GIS
7.- Development of module adapter for DELFT-FEWS (Deltares) for operational hydrology and flood forecasting
I want to calculate watershed health using different parameters. The above mentioned parameters are part of the analysis.
I have created the soil user file and now working of LULC file. I have done almost all only remaining are following:
Both belongs to urban landcover, so its code must come from Urban database and accordingly code ID will be assigned in the user define Land-use text file. AM I right?
Secondly, Desert, Dryland and Plaindryland I am still struggling how to replace them from the land cover closest category.
Could you please guide me how to fix these problems.
Thanks in anticipation.
I would like to know what are the relationships among watershed health, watershed sustainability and watershed stability!
Please share your experiences with me.
I have studied an area of rain forest which presents a strong gradient of variation in soil moisture and nutrient. The florestal inventory was conducted in 42 plots of 5-25 meters, distributed in seven lines going through three compartments, in order: 1) A floodable plain forest in a organic soil; 2) Intermediary assembly located in a soil with a steep slope; and 3) a dry forest located in the highest place, with poor white sand soil.
For now, i intend to evaluate the water table variation, but i´m not sure how deep and how many piezometers should be needed to perform multivariate analyses involving plant community and soil water content. Initially, would be interesting install 42 piezometers, 1 per plot, but this would be very difficult to perform. Besides, i am not sure if piezometers of 1,5 meters would be deep the enough to access predictive informations about the influence of soil water content in plant community composition.
I am looking for data set to develop a flood forecasting system specifically for an agriculture dominated watershed. The requirements include a) fine resolution DEM b) land use type and soil hydrologic group c) hourly/sub-hourly rainfall data for a minimum of 30 years d) hourly/sub-hourly stream flow data and e)demographic details of the area. It would be helpful if you suggest any data repository/experimental watershed for collecting the above mentioned data. I assure you that the services offered will be duly acknowledged.
We observed a huge difference between simulated and observed outflows from a catchment during a hydrological modelling exercise in HEC-HMS. The catchment contains numerous ponds and smaller lakes (of varying areal extent), lacking operational data. How can we account for the effect of these storage structures in the hydrological modelling?
What data do we need?
I got 35 years of daily data of rainfall and river discharge.
I am working on this project for my final year research project in civil engineering.
Dear Researchers, I have daily flows data 1961-2015 and some of the months flows data is missing. This missing period varied; 1 mont, 1.5 months, 7 months, randomly. I would like to ask how to generate this missing data? Please share your expertise and skills. Thanks in anticipation Regards Naveed.
I am looking for runoff data (ground or satellite) especially for Khartoum, Sennar, El Deim, Kessie and Bahir Dar stations during the period (2008-2018).
Thanks for any help.
I am almost always working on a catchments without river discharge. I am trying to think of a smarter way of calibration the rainfall-runoff (RR) model. Common practice has been to calibrate nearby catchment with data and transfer the parameters. Has anybody tried to use the hydrodynamic model to calibrate the RR model?
Hai everyone, I am working of SWAT CUP for my validation and calibration. After doing first calibration , i got the value of NS equals -0.17. Then when i am again doing my calibration again to get the exact value of NS , i am facing an issue that "the application has requested the run time to terminate in an unusual way ". i attached the screenshot of the problem what i am facing now. Can anyone give a proper solution for this , so that i can move further.
Need to understand the long term changes in the release from upstream storages to the intensively cultivated delta.
Normally flows are from July to Feb months only, over the years flow has reduced to Aug to Jan.
flow data is available for a network of 17 gauging stations in delta. how it can be studied ?
any suggested literature ?
Can i do the analysis in Excel ? if not please suggest some software ?
Scientific efforts in post-fire hydro-geomorphology seem to agree on the dominating importance of the hydro-climatic regime (i.e. precipitation type and timing) on the response of a watershed after a fire. Although variability exists according to scale, fire severity, or soil nature, it appears that post-fire heavy rain or snowmelt can be associated with higher runoff and erosion and eventually higher water and sediment yield.
However, I'm wondering how much topographical settings of a watershed, or of the burned area, can also act as a control of post-fire hydrogeomorphic response, i.e. runoff and erosion? By topographical settings, I mean elevation, ruggedness, slope steepness, curvature, and length, aspect, shape of the watershed or of the burned area...or any metric you could think of to describe a terrain.
To my knowledge, it is something that has hardly been addressed, and only a few papers seem to mention this (I'd be willing to read any reference you may share with me). It also seems that papers focusing on post-fire changes in water or sediment yield, or debris flow, tend to focus on locations displaying a certain level of topographical complexity.
I guess it draws 2 other questions, rather provocative, beside my introductory one:
- Is post-fire hydro-geomorphology "biased" toward complex terrains, especially steeper terrains, because a response is more likely according to general runoff and erosion processes?
- Can we generalize current scientific knowledge and argue that complex terrains, especially those displaying steep slopes, are more likely to experience greater post-fire changes in their hydrogeomorphic regime?
I have tried to simulate the hourly rainfall runoff events, peaks are matching but after peak the discharge at which it has to recede is not as expected as seen in the attached file.
Can you please advice me the tuning parameters for that in HEC HMS.
The data that I have collected came from height gauging station which has an acquisition interval of 10 minutes and a weather station that records every 15 minutes. The site where the gauging station is located has an established rating thus I can derive stream discharge.
I am trying to create a unit hydrograph of storm and heavy rainfall events using these data sets. I have tried using the method stated from the link attached. But I am not sure if the results I have arrived at is satisfactory.
If possible, do you know any method that I could use to create a unit hydrograph? If so, what are the details of this method (procedure, etc.)?
Thanks in advance!
I would like to know if it is possible to convert the duration of a unit hydrograph.
For example, I have a unit hydrograph of a storm event that lasted for about 50 hours with a peak discharge after 3 hours. How can I convert this 50-hour hydrograph into a 4-hour duration with its peak discharge being reached at around the 30-minute to 1-hour mark? Has anyone been in a similar situation?
Thank you in advance!
Which method do you recommend for estimating monthly and annual runoff data when you have monthly and annual inflows in million gallons, monthly and annual precipitation and temperature data as available data
if you have soil moisture storage at depth (10cm), precipitation, infiltration and runoff value. you can calculate evapotranspiration for catchment?
do you agree with this procedure.
or this procedure is wrong?!!!
1. Infiltration rate during rainfall event expressed by runoff subtraction from rainfall event according to (Butterworth et al, 1999).
If= P-R .......... (1)
2. The mass balance for infiltration may be expressed by the change in storage over a given period of time, where ∆SMsat-pre equals the difference between the inflow rate infiltration If in (∆t), and outflow rate infiltration, If out (∆t) by TRENT UNIVERSITY STAFF, so If out (∆t) expressed in follow equation:
If out (∆t) = If in (∆t) - ∆SMsat-pre …………. (2)
If out (∆t) = outflow rate infiltration (mm/day)
If in (∆t) = inflow rate infiltration (mm/day)
∆SMpre-sat = difference between soil moisture content pre rainfall event and during rainfall event at saturation condition (mm).
3-The hydrologic processes in both catchments model include infiltration, runoff, soil evaporation, plant transpiration, and deep drainage. From the previous steps, the outflow infiltration considered as a deep percolation, so we can calculate soil catchment evaporation during 24 hr by root zone water balance equation (Lu Zhang et al., 2002):
Epan = (P + θSMpre.) – (Dp + Q + θSMaft.24hr) ………. (3)
Epan = Soil catchment evaporation (mm/hr).
P = rainfall event (mm/hr).
θSMpre. = Soil moisture content before rainfall event (mm/hr).
Dp = Deep percolation (mm/hr).
Q = runoff event (mm/hr).
θSMaft.24hr. = Soil moisture content after 24 hr from rainfall event (mm/hr).
4. Allen et al. (1998) equation used to calculated daily potential evapotranspiration used daily reference soil evaporation corrected by pan coefficient factor (0.65 – 0.70) related to region, as follow:
ETo = Kpan × Epan ……………. (4)
ETo = reference evapotranspiration (mm/day).
Kpan = pan coefficient factor (0.65 – 0.70).
Epan = pan evaporation (mm/day).
after them by water balance equation we calculate ground water recharge ?!
(P) = (Q + ET ± ∆GW ± ∆SM) .
P = Precipitation rate in (mm).
Q = Stream flow (mm/sec).
ET = Evapotranspiration rate (mm).
∆GW = Ground water storage changes in (mm).
∆SM = Change in soil moisture content (mm).
Sarbast I. Abdi
I would like to know, is it feasible to find out the trend in daily stream flow of very short duration (2 years) to understand the hydrological process? What are its applicability? Any research paper related to this if available then can you please share it.
Our study focuses on the impacts of grazing on hydrological processes, mainly surface runoff, evapotranspiration, and soil loss. We study different animals (with soft-padded feet and hooves) and different grazing intensities, and focus on mountainous areas in Peru. We found empirical evidence in many regions of the world, but not comprehensive review that could support a simple modeling approach.Thanks in advance!
In my site, ground water table is very deep (>50 m), and the primary water source for plants is from soil water recharged by precipitation. Now I have daily soil moisture observations within the 0-280 cm, and I want to estimate plant water uptake profile by using these observations. First, soil moisture in the 0-10 cm was kicked out because its changes are dominated by soil evaporation. Next, I computed daily changes (δi) of soil moisture in the 20-280 cm (at eight depth intervals). Negative δi values suggest plant water uptake occurs, and positive δi values mean soil water is recharged by rainfall. Is it reasonable in this manner? Thanks in advance for any help.
Hi All, I am working in i-Tree Hydro model which depicts the change in runoff due to change in tree and other land cover. After simulating the model, the results show that the Baseflow, pervious and impervious flows also have been reduced. Whereas, the baseflow should have been increased with a decrease in both other flows. The input parameters are percentage of tree, shrub, impervious and water cover and evergreen tree and shrub cover and the meteorological and evapotranspiration data. Please suggest some measures or change in percentage of parameters so as to get a higher baseflow.
I have completed the simulation through the SWAT model. However, as I don't have the measured flow data, I don't know the accuracy of model output, and I can't adjust the parameter based by measured data, which could improve the model output.
A professor told me that an uncalibrated, or limited calibrated model is still a useful management tool. In fact, he believes SWAT was developed in part to evaluate ungauged watersheds.
However, I believe that it is necessary to verify the accuracy of model output and adjust the parameter to improve the model output through comparing the simulated flow data and measured flow data.
I can't continue this work now, what should I do now? Can I apply the simulated data without verifying?
Is there any other model more accurate than MODFLOW?
I think MODFLOW only simulates consumptive use of irrigation water, not the returned irrigated water. In other words, the effects of pumped water being returned directly to the immediate aquifer are ignored in MODFLOW.
Also how accurate MODFLOW is in simulating interception by crops, to estimate the water balance in that area. Especially if i want to test different scenarios such as what will happen to water balance (especially ground water table), with landuse change
Dear friends I am working on water balance in a watershed. Assume that water balance equation is as following:
In which P is precipitation, ET is evapotranspiration, In is infiltration, Int is interception and R is surface ruoff. Rainfall interception by vegetation cover is calculated using remote sensing techniques. Now, I wonder if I should eliminate all calculated interception from the water balance. As we know a proportion of interception becomes evaporated and the other part becomes infiltrated.
My area of interest is small rural catchment of 40 km², located in the sahelian climat (<600 mm yearly rainfall). In the past years (~1970-19990) a large portion of the watershed was covered with vegetation. Due to the population increase, and a higher demand in food, the cultivated portion of the watershed grew quickly. Due to anthropic stress and very poor land management and land conservation practices, more than 50% of the watershed is now degraded (bare soil) with soil crusts and sealing as described by Casenave and Valentin (see provided links below). As such, those specific soil surface characteristics affect runoff production, increasing discharges even though the total amount of annual rain tends to decrease.
I am interested in modeling runoff and sediment to assess erosion. In am interested in the spatial distribution of runoff and erosion rates. SWAT seems to be a good candidate for my specific study case. But I would like to consider the fact that throught the years, specific land units representing homegeneous soil units with specific soil surface characteristics evolve in terms of shape, size, location in the watershed. Those informations will be derived from a series of Landsat Images of the watershed on the 1979-2016 period. Is there any way to couple such needs with SWAT ? Or can ayone suggest a better approach ?
I'm interested to analyse the contribution of different sources such as snow/glaciers, GW, rainfall, etc to the total flow of a river. Which model would be the best fit particularly to the Himalayan region? Please suggest
If I have spatial polygons describing thousands of river catchments in a large region, what is the smartest way to define a relational system between catchments? I'm familiar with concepts from computer science such as linked lists and tree directories. I don't want to re-invent the wheel. Has anyone come up with the definitive method to store the relationship between catchments so that, when needed, it's possible to answer questions such as:
> which catchments are within this catchment;
> which catchment does this catchment drain into;
> what is the chain of catchments upstream and downstream of this one.
I think it's an interesting problem probably with multiple solutions. I would appreciate any thoughts/discussion.
Modelers can make any thing possible, so answer could be 'no'. But from real physics point of view answer could be 'yes'. I am eagre to know ways to tackle the situation if answer is 'yes'.
“some thing is better than nothing’ this statement could be more true in routine way or issues, but may be not equally factual in natural science like hydrology. I would like to put a hypothetical scenario - when for a given catchment (say 2000 ha) we have continuous river flow data at the interval of 6 hrs, but the available rainfall data is only at 24 hr time step i.e. daily value. River has continuous flows, giving hydrographs of broader bases say 15 to 20 days atleast. For generating runoff prediction models, this partially gauged catchment is as good as an ungauged catchment ( in want of accurate rain input data). How to deal such situation ? What are the innovative ways to move ahead for coming over to such deficit at one end and carving out some regional predictive models for totally ungauged locations on other hand, eliminating uncertainties of predictions/simulations in accordance to prevailing physics/phyisiographical configurations of catchments.
I used a rainfall-runoff model to study catchment hydrology and got time-to-peak [hour], peak discharge [cms], and hydrograph duration [hour] for several catchments. Is it possible to construct hydrographs using these three inputs?
I assume some optimization methods are required to create specific shapes of hydrographs...Any ideas which curve should I use and how to create it?
i want to know about rainfall-runoff method that can be convert rainfall to runoff discharge specify for small,steep catchment area.
The runoff coefficient for a watershed gives a fair idea about the input-response relationship for the system. The major factors that affect the rainfall-runoff relationship can be broadly categorized into Physiographical and Climatological factors. The physiographical factors involve land use land cover, soil type, underlying geology, stream density, elevation, stream slope, land slope, etc.While the climatological factors include rainfall amount, rainfall intensity, antecedent soil moisture, evapotranspiration, etc. The effect of physiographical factors can easily be ascertained but how to relate the climatic parameters such as effect of evapotranspiration rates on runoff coefficient. Are there any metrics or statistical measures to analyze them?
I am using ArcHydro and HEC-GeoHMS extension of GIS for HEC-HMS. Facing the issue while determining the River Slope using HEC-GeoHMS. Error is attached herewith. Kindly guide me how to further proceed?
Conservation of mass and momentum ' the big theory always remains with us for generations. According to it total quantum of water on globe will be same, even to the accuracy of a single drop. But its location and form will change in most unpredictable manner with infinite uncertainties, which will remain exactly equal to the level of unpredictable & uncertain intrusion we people are doing or giving to nature and whole natural system.
My question reflects a virtual scenario, assuming a when not a single drop in ground, all is either on surface or in atmosphere? What we must do and how we prepare ourself for this, which in my opinion can never be said 100% hypothetical question ?
I love to have comments of great experts here. Also I like to supplement that it is based on a quote from one of the famous NASA scientist ..who is going to speak and debate on it...soon
I'm using a water level logger named 'HOBO U20'.
According to its manual, the Logger records absolute pressure, which
is later converted to water level readings by the software. Normally, atmospheric pressure is 100 kPa at sea level, but changes with weather and altitude. Because my study site is in the middle of the mountain area, HOBO U20 Water Level Logger can be used as a barometric reference to compensate for barometric pressure changes.
I use two loggers and one is set in the stream to collect water level data and the other is set on the ground as a barometric reference.
I would like to know the principle to deduce the water level from both pressure data. Is there the relationship like some mathematical formula ?
I was wondering if anyone knows where I can find Haiti streamflow data because I will be working on it soon it seems to me it is not available at
it seems to me it is not available on their website in this link
Availability of rainfall intensity data at micro scale is a big constraint in attempting rainfall-runoff modeling. often we have daily rainfall data . Is it possible to use that time series , to synthetically derive hourly rainfall values . I hope to get educated and invite supportive stuff if any of us have ?
I am looking for the value of the HDI, that it would be possible to separate USGS gauges to non-urbanized, semi-urbanized and urbanized watersheds based on that. As I am working in the ArcGIS, I need quantitative values for this index.
I research effects of riparian zone on water quality. Have you any idea about this issue?
I am looking for ISO 7066-1-1989, Its basically for Assessment of uncertainty in calibration and use of flow measurement devices -Linear calibration relationships. Please share it if some one have. I will be thankful for this.
I have worked out the sediment loss from two micro watersheds. I am not sure whether the obtained sediment loss values can be categorised as 'within permissible limit'. Pleas guide.
I have only one hydrometric station in the output point of the watershed. but i need a map for all the watershed. How can I access to the maps of my variables or related variables.
Our research involves observing the contribution of trees in lessening floods along a watershed area through rainfall interception. To measure rainfall interception in a 900 sq.m area, we plan to use throughfall collectors and stemflow collars. How many throughfall collectors would be ideal to measure rainfall interception in an area this wide and what would be the most effective way to position them in order to obtain accurate results?
Ideally this would be a 2-person raft for deploying instruments (e.g. CTD, LISST) off the side. I like the look of the Alpacka rafts but have never used one and don't know how stable they are, especially when trying to pull up an instrument from 50m depth. I'd rather not go into the drink. Any suggestions welcome!
i am working on dssat model v 4.6 for climate change studies for rice wheat crop but i am using the automatic irrigation option for irrigation which after simulation gives output effective irrigation less than the recommended for both the crops so i want to know how to increase it to the recommended. what is the reason that it is happining so i am also attaching the file. please have it in attachments