MN GIS/LIS NEWS
Summer 2012
ISSUE 68

MN GIS/LIS NEWS
The Newsletter of the Minnesota GIS/LIS Consortium

Table of Contents

MN GIS/LIS Consortium

From the Chair
Member Portal Upgrade 
2012 Spring Workshops 

State
New State GIO
State Govt IT Consolidation
Driftwatch Crop Registry
GLO Field Notes Online 
Altered Watercourse Project
Emergency Prep. Blog Update
PCA websites

Regional
GECCo Report
Spatial Hotdish

Make-A-Map Upgrade

Local
New Ramsey Co Map Site 
Dakota Co Transport Plan 
State Monuments on Google Earth

Federal
National Elevation Assessment
Landsat 40th Anniversary

Higher Education
GISSO Job Fair Report

Other Places
Future Trends in GIS Mgmt

 

 

Minnesota Statewide Altered Watercourse Project Underway
By Ben Lundeen, Minnesota Pollution Control Agency 

Stream channel modification, such as the straightening of channels, removal of oxbows and dredging, is a significant source of habitat destruction in many freshwater ecosystems. The historic and current extent of stream channel modification in Minnesota is relatively unknown. Several GIS layers, such as the National Hydrography Dataset (NHD), Public Waters Inventory, and Minnesota Department of Transportation BaseMap, provide some information on altered watercourses; however, these data are often outdated or spatially limited.

In 2008, the Minnesota Pollution Control Agency initiated a pilot project with the Minnesota Geospatial Information Office (MnGeo) to develop a methodology to identify stream segments that have been altered through channelization and ditching using GIS. Currently, MPCA, MnGeo and the Minnesota Department of Natural Resources are collaborating to refine the methodology and apply this tool statewide. The methodology primarily uses statewide aerial imagery and LiDAR-derived elevation data along with several reference layers. To the best of our knowledge, this project is the first comprehensive effort to distinguish altered watercourses statewide in Minnesota.

MPCA will use this information to aid in the interpretation of stream survey information, which is used in water quality assessments of Minnesota’s rivers and streams. Specifically, MPCA is developing a refined stream use designation process known as Tiered Aquatic Life Uses (TALU). An accurate statewide determination of altered stream segments based upon the current NHD linework will assist in assigning the correct beneficial use class for a stream under the TALU framework.

This project is being conducted in support of MPCA’s water quality monitoring and assessment program, with support from the Clean Water, Land, and Legacy Amendment’s Clean Water Fund.

For more information, see the Altered Watercourse Project webpage or contact Ben Lundeen at benjamin.lundeen@state.mn.us or 218-316-3894.