MN GIS/LIS NEWS
Winter 2007-8
ISSUE 51

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

Table of Contents

MN GIS/LIS Consortium

Conference Review
From the Chair
Competition Results
Budget News

State
GLO Notes Online
Ag/DNR Collaboration Water/Utilities/Telecom Info
NSGIC highlights

Governor's Council
Open for Requests

Regional
MetroGIS Business Plan

Local
Goodhue Wetland Model

Federal
Pipeline Viewer
Stream Class Problems
Computer Energy Standards

Higher Education
UofM GIS Portfolio
Certificate at Mankato
St. Mary's Update

K-12 Education
MIIM Internet Mapper

Non-Profits
GITA Conference

People
Craig Wins Award
Zenk NGS Advisor

Other Places
GIS Jobs in Demand
Landsat Island

 

Identifying Drained Wetlands – A Joint Project Utilizing ESRI’s Model Builder
By Sarah Schrader, Goodhue County GIS Specialist

In Summer 2007, Beau Kennedy of the Goodhue County Soil and Water Conservation District (SWCD) approached Goodhue County GIS Specialist Sarah Schrader to assist with a project identifying drained wetlands throughout the county. With the help of Adam Birr of the Minnesota Department of Agriculture, a methodology was created to first identify potential wetland areas. Through terrain analysis, staff was able to identify sinks/depressions in the topography that lay within both flat areas and hydric soils. The resulting data will target areas for SWCD staff to verify in the field and using orthophotography whether a wetland exists or whether it has been drained. SWCD staff can then contact landowners regarding possible funding availability for wetland restoration.

Goodhue County’s 2 foot LIDAR-based contours were used as the base data for the entire project. Once the methodology and variables had been field-tested and finalized, Sarah created a model using ESRI’s Model Builder to streamline the data processing. Fifty-two separate processes were combined into the final model (see graphic). The data processing requirements were so large that the computer could not handle processing areas larger than a quarter township. In total, it took over 148 hours to process the data for the entire county with each quarter township taking an average of 1.8 hours to complete. The model was run during business hours as well as overnight and on weekends. Using the model saved many hours of staff time by streamlining the multiple steps into one seamless process.

After the data processing was complete, staff merged and dissolved the separate resulting data files into one final layer that covered 27,230 acres or 5.5% of the total land area in Goodhue County. The project was finished in August 2007, and SWCD staff is currently in the process of validating the results in the field. Sarah recently presented at the GIS/LIS Consortium Conference regarding this project.

For more information about the use of Model Builder for this project or to request a copy of the model or description of the process, contact Sarah Schrader at 651-385-3193 or sarah.schrader@co.goodhue.mn.us

For more information about the methodology used for this project or how the project results are being used, contact Beau Kennedy at 651-923-5286 ext. 114 or beau.kennedy@mn.nacdnet.net