Hydrologic watershed modeling
This presentation is the property of its rightful owner.
Sponsored Links
1 / 24

Hydrologic/Watershed Modeling PowerPoint PPT Presentation


  • 124 Views
  • Uploaded on
  • Presentation posted in: General

Hydrologic/Watershed Modeling. Glenn Tootle, P.E. Department of Civil and Environmental Engineering University of Nevada, Las Vegas [email protected] , Ph.D. Department of Civil and Architectural Engineering University of Wyoming [email protected] Questions?.

Download Presentation

Hydrologic/Watershed Modeling

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Hydrologic watershed modeling

Hydrologic/Watershed Modeling

Glenn Tootle, P.E.

Department of Civil and Environmental Engineering

University of Nevada, Las Vegas

[email protected]

, Ph.D.

Department of Civil and Architectural Engineering

University of Wyoming

[email protected]


Questions

Questions?

  • Who has used / developed a hydrologic model?

  • What model(s) did you use?

  • Examples


Conceptual model of watershed modeling

Conceptual Model of Watershed Modeling

  • Typical Input

  • Topography

  • Soil Characteristics

  • Land cover

  • Land use

  • Meteorological data

  • Typical Output

  • Streamflow

  • Subsurface Flow

  • Depth to water table


Steps to hydrologic modeling

Steps to Hydrologic Modeling

  • Delineate watershed

  • Obtain hydrologic and geographic data

  • Select modeling approach

  • Calibrate/Verify model

  • Use model for assessment/prediction/design


What is a watershed

What is a Watershed?

  • Area that topographically contributes to the drainage to a point of interest

Natural Watershed

  • Points of Interest

  • Road crossing

  • Stream gage

  • Reservoir inlet

  • Wastewater treatment plant

  • Location of stream restoration


Urban watershed

Urban Watershed


Usgs quad map

USGS Quad Map


Digital elevation model dem

Digital Elevation Model (DEM)

  • Digital file that stores the elevation of the land surface a specified grid cell size (e.g., 30 meters)


Geographic data

Geographic Data

  • Land use

  • Land cover


Geographic data1

Geographic Data

  • Soil type/classification


Hydrologic data

Hydrologic Data

  • Meteorological Data

    • Temperature

    • Precipitation

    • Wind speed

    • Humidity

  • Extrapolation of point measurements

    • Theissen Polygons

    • Inverse distance weighting


Hydrologic data1

Hydrologic Data

Streamflow

  • Hydrologic Data

    • Streamflow

      • Peak discharge

      • Daily flow volume

      • Annual flow volume

    • Soil moisture

    • Groundwater level


Modeling approaches examples

Modeling Approaches (examples)


Basis for many hydrologic models

Basis for Many Hydrologic Models

  • Hydrologic Budget (In – Out = ΔStorage)

Transpiration (T)

Streamflow (Q)

Evaporation (E)

Groundwater out (GWout)

Reservoir

Precipitation (P)

Groundwater in (GWin)

Infiltration (I)

Watershed

(P + GWin) – (E + T + I + GWout + Q) = ΔStoragereservoir


Which model should be used

Which Model Should be Used?

  • It Depends on:

    • What time scale are you working at?

    • What hydrologic quantity are you trying to obtain?

    • What data do you have for your watershed?

    • How fast of a computer do you have?


Spatial scaling of models

Spatial Scaling of Models

Semi-Distributed

Parameters assigned to each grid cell, but cells with same parameters are grouped

Fully-Distributed

Parameters assigned to each grid cell

Lumped

Parameters assigned to each subbasin

A3

A1

A2


Stanford watershed model hspf

Stanford Watershed Model(HSPF)

  • Physically-based and continuous simulation


Variable infiltration capacity vic 3l

Variable Infiltration Capacity (VIC-3L)

  • Continuous simulation and physically-based

  • Macroscale hydrologic model that solves full water and energy balances


Vic 3l example

VIC-3L Example


Calibrating a model

Calibrating a Model

  • Typically the model is calibrated against observed streamflow data

  • Depending on the model complexity, parameters are adjusted until observed streamflow equals model streamflow

  • Which observed value to use:

    • Qpeak

    • Qvolume

    • tpeak

Qpeak

Q

  • tpeak

  • Qvolume

t


Sensitive parameters

Sensitive Parameters

  • Precipitation

  • Soil parameters

    • Hydraulic conductivity

    • Soil water holding capacity

  • Evaporation (for continuous simulation)

  • Flow routing parameters (for event-based)


Uncertainties

Uncertainties

  • Precipitation

    • Extrapolation of point to other areas

    • Temporal resolution of data

  • Soils information

    • Surveys are based on site visits and then extrapolated

  • Routing parameters

    • Usually assigned based on empirical studies


Use of models

Use of Models

  • Assessment

    • What happens if land use/land cover is changed?

  • Prediction

    • Flood forecasting

  • Design

    • How much flow will occur in a 100 year storm?


Questions1

QUESTIONS


  • Login