The study of the movement, distribution, and quality of water on Earth and other planets, including the hydrologic cycle, water resources and environmental watershed sustainability.

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3
votes
2answers
60 views

Determining steady flow in HEC_RAS 4.0

While using HEC-RAS 4.0 Beta, how to set PF1 in Steady Data Flow?
2
votes
2answers
49 views

ArcGIS are two rasters the same? - including null values

I am working on a task to calculate Height Above Nearest Drainage (HAND) - that is the height above the nearest point along the flow path that is on a drainage - not the geographically nearest ...
3
votes
1answer
443 views

How to calculate runoff in Rainfall Analysis?

I have 30 years daily rainfall data. How can i calculate the mean monthly runoff, minimum monthly runoff and maximum monthly runoff with the available rainfall data using GIS? I would like to use ...
1
vote
1answer
55 views

Flow accumulation raster loading in QGIS 2.4.0 with null values (but flow direction loading ok!)

I have been tasked with creating an open-source hydrology dataset for a community group. To do this I have exported the flow direction and flow accumulation rasters from ArcMap as TIFF files and then ...
0
votes
1answer
59 views

How are minor tributaries determined?

What are the criteria to determine if river A is a major or minor tributary to another River B? Is stream order the only deciding factor i.e. the highest order is the main stem, one less order is a ...
0
votes
1answer
48 views

Problem for slope map

I want o create one slope map for my model but I have one big problem. I have contours lines and mass points and I create a DEM using topo to raster but if I want to create a slope map from that DEM I ...
0
votes
1answer
25 views

1:250 streams data - USA wide - where can I find it?

I have 1:250 streams data for a few western states. I find this scale to be excellent in many settings as base hydro data. I have never been able to find a USA or better yet, NA wide dataset of this ...
0
votes
1answer
534 views

Calculating longest flow path and avg. slopes for catchments with qgis?

I am a hydrologist and their are 2 important pieces of information I need for modeling. I need to know the longest flow path for each sub catchment in my area of interest and I need to know the ...
4
votes
0answers
120 views

Flow direction generated for river is incorrect

I am trying to generate a hydrologic model and I can not really proceed on the next processes. I have this problem on generating flow direction. I have already executed fill sinks and the next is flow ...
3
votes
0answers
144 views

Extracting flow accumulation to stream shapefile

I would like to create a shapefile that displays the flow accumulation for a given point in a stream channel. Is this possible? My client wants a map that shows the accumulated flow/catchment area ...
3
votes
0answers
119 views

Which geostatistical tools to use to determine surface changes over 40 years?

I have a data from the Weather station with SWEmax (snow water equivalent) collected over 40 years. I need to interpolate the data over my river's watershed and then, somehow, determine the ...
3
votes
0answers
206 views

Pipe Network: Computing the inflows for systems with multiple reservoir (input source)

Let's say, for the sake of simplicity, we have the following Y Shape water pipe network: S1 and S2 are the reservoirs ( input source), Sout is the water demand where water is drawn out for ...
2
votes
0answers
123 views

Creating water surface from vector line in QGIS

I want to create a raster surface representing the flood level in a creek based on output from a 1D hydraulic model. I receive a 3D profile of the water surface in a creek line as a 3D Polyline ...
1
vote
0answers
23 views

QGIS SAGA Channel network error: Input layers do not have the same grid extent

I am trying to follow along with this exercise using my own DEM. I have done the first step, creating the catchment area, with no trouble. When I try to run the Channel network algorithm, however, I ...
1
vote
0answers
23 views

create a weight raster for a hydrology analysis

I determine affecting parameters of flood flow ( evaporation,vegetation,soil type, rainfall etc.). Then, I start to analysis using Arc Hydro. How do I relate among of affecting parameters? How can ...
1
vote
0answers
20 views

Interpreting some hydrology data

This is the historical feed of the Keystone dam for October 2014: http://www.swt-wc.usace.army.mil/chartbin/KEYSOct14.shtml Here is the real time feed: ...
1
vote
0answers
57 views

Determining uppermost point in stream based on gradients?

I am trying something new and was hoping someone out there may have done this same process or something similar or may have a best approach. For this particular project I am working with ArcMap ...
1
vote
0answers
85 views

r.stream.* commands do not work in qgis environment

I have been working for a while with some grass commands in QGIS environment (r.watershed, r.terraflow, r.thin, r.to.vect etc) with out any problem. I haven't been able to get any results at all from ...
1
vote
0answers
255 views

Morphometric and hydrological analysis with Python and ArcGIS

How can I write a program using python, that calculates some morphometric and drainage indexes using numeric attributes in the attribute table with ArcGIS? The data I have in my table are area and ...
0
votes
0answers
78 views

ArcGIS ModelBuilder Clip Raster by Polygon Error

My task is to derive the hypsometric integral and hypsometric curve for a lot of drainage basins. Since it is very time consuming to do this manually, i have created a model (with help from this ...
0
votes
0answers
45 views

Delineating sub-basin

Could you please help with delineation of sub-basin from SRTM DEM? From this DEM I've already delineated basin using hydrology tools in ArcGIS 10.0. Now as my study area is a sub basin within this ...
-1
votes
0answers
34 views

Stream Link (Spatial Analyst)

I implement "stream link" algorithm with Hydrology Tools in ArcGIS. It generates unique values to sections of a raster linear network between intersections. Which method does it use? How does it work? ...