Lthia 2007 2008 upgrades and training
This presentation is the property of its rightful owner.
Sponsored Links
1 / 35

LTHIA – 2007 -2008 Upgrades and Training PowerPoint PPT Presentation


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

LTHIA – 2007 -2008 Upgrades and Training. Bernard A. Engel Tong Zhai Larry Theller Agricultural and Biological Department Purdue University In conjunction with POLIS Center, IUPUI and Indiana Dept. Environmental Management. Contents. Basic concepts New data layers

Download Presentation

LTHIA – 2007 -2008 Upgrades and Training

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


Lthia 2007 2008 upgrades and training

LTHIA – 2007 -2008Upgrades andTraining

Bernard A. Engel

Tong Zhai

Larry Theller

Agricultural and Biological Department

Purdue University

In conjunction with

POLIS Center, IUPUI and

Indiana Dept. Environmental Management


Contents

Contents

  • Basic concepts

  • New data layers

  • How web model works

  • Integration with IWQA

  • Training in 2008


Basic model concepts

Basic Model Concepts

  • Model is easy to run

  • Always gives an output…

  • Important to understand assumptions

  • and limitations


Assumptions

Assumptions

  • Water flows across the surface to form flowshed

    • no storm drains

  • Water equally spread across landscape

    • No routing

  • Average antecedent moisture

    • soil is not saturated or frozen

  • Rainfall is evenly spread in local area


Limitations

Limitations

  • Accuracy of landuse and soil data

    • Big limitation

  • Accuracy of runoff curve number

    • Hydrological impacts are understated

    • LID not reflected

  • Accuracy of published NPS relationship

    • Lead in runoff based on 1990’s models


Long term hydrologic impact assessment lthia

Long Term Hydrologic Impact Assessment (LTHIA)

  • Calculates the chemistry and volume of runoff water, based only on landuse and soil type.

  • Changing the landuse in an area will change the typical runoff chemistry.

  • This uses assumption called “curve-number.”

  • LTHIA in use for > 5 years.


Process flowchart

https://engineering.purdue.edu/~lthia

Process Flowchart

Outlet Point Selection Using Aerials, roads, or streams

Run Watershed Delineation

To get contributing area

Watershed Delineation Result

Examine maps

Reflect Land Use Change Using Online Digitizing

Run L-THIA

Runoff and NPS Output/Impact Evaluation


Lthia 2007 2008 upgrades and training

The screens used in the model


Lthia 2007 2008 upgrades and training

Landuse 1

Landuse 3

Landuse 3

Soil A

Soil B

We break soils into 4 hydrologic conditions, which are used to estimate runoff volume.

We break landuse into 8 basic types, which are used to estimate chemistry.


Lthia 2007 2008 upgrades and training

LTHIA isolates the flowshed to estimate the runoff, so it calculates runoff for the -shed.


Lthia 2007 2008 upgrades and training

Raster input

  • Edit raster landuse layer

  • and change scenarios


Lthia 2007 2008 upgrades and training

The software uses raster files of landuse and soil


Lthia 2007 2008 upgrades and training

Curve Number Basics:

rainfall to runoff ratio for different surfaces

Direct

Runoff

Rainfall

http://www.ecn.purdue.edu/runoff/documentation/scs.htm


Lthia 2007 2008 upgrades and training

Averaged mass of NPS contaminant from each landuse

EMC Table


Lthia 2007 2008 upgrades and training

Data Issues:

Working with 10 meter DEMS means we can not use watersheds larger than 10 digit.

So, if the user clicks on the mouth of the Wabash or the Tippecanoe River, they get the first upstream 10 Digit watershed.

All contiguous 10 Digit watersheds are supported.


Lthia 2007 2008 upgrades and training

Take-Home points

DEM is only used to calculate flowshed

DEM is not used for erosion – or runoff

Runoff is based on surface type – not slope

won’t account for frozen ground

30 year average rainfall

Chemistry is based on landuse averages


Databases provide input

Databases provide input

  • Weather data (30 years of real rainfall)

  • Soil data (SSURGO )

  • Elevation data 10m DEM (for contributing area)


Process for web gis tools

https://engineering.purdue.edu/~lthia

Process for Web-GIS Tools

Outlet Point Selection Using Aerials, roads, or streams

Run Watershed Delineation

To get contributing area

Watershed Delineation Result

Examine maps

Reflect Land Use Change Using Online Digitizing

Run L-THIA

Runoff and NPS Output/Impact Evaluation


Lthia web site

LTHIA Web site

Choose to click a point, input X and Y, or select a 14 – digit watershed


Lthia 2007 2008 upgrades and training

Watershed Delineation and Result Page


Watershed delineation and result page

Watershed Delineation and Result Page


Results display

Results Display


Change land use in the watershed using online digitizing tool

Change Land Use in the Watershed Using Online Digitizing Tool

For Example,Add Low Density Residential, Commercial, and High Density Residential Areas


Scenario results page

Scenario Results Page

Present Land Use Data

After Change Land Use Data

Application Buttons forHydrological Model Operation


L thia input page after changing land use

L-THIA Input Page After Changing Land Use

Multiple scenarios – offer multiple development options. User constructs scenario by online digitizing.


L thia result runoff tables

L-THIA Result Runoff Tables

Can display pre-and post calibration and also land-use change scenarios.


Comparison chart for runoff and land use to evaluate the land use change impact on hydrology

Comparison Chart for Runoff and Land Use to Evaluate the Land Use Change Impact on Hydrology


Nps pollutant loading chart

NPS Pollutant Loading Chart


Print and download page

Print and Download Page


Long term hydrologic impact assessment lthia1

Long Term Hydrologic Impact Assessment (LTHIA)

  • Added connection to the Indiana Water Quality Atlas

  • 2001 NLCD landuse statewide

  • Landuse based on parcels, selected cty

  • SSURGO soil

  • better DEM (10 meter)

  • NHD High –resolution stream layer


Near future calibration module in development

Near Future:Calibration module in development:

  • 15 counties landuse from parcel data

  • Hands-on Training


Lthia 2007 2008 upgrades and training

The End

Thank You

https://engineering.purdue.edu/~lthia


  • Login