Ravalli County Land Suitability Analysis
Total Page：16
File Type：pdf, Size：1020Kb
Ravalli County Land Suitability Analysis A Tool to assess development suitability based on EXISTING INFRASTRUCTURE, Water resources, Wildlife, Working Lands, Open Lands, AND PUBLIC HEALTH AND SAFETY in Ravalli county, montana JUNE 2008 Prepared By: Ravalli County Planning Department 215 South fourth Street, Suite F Hamilton, MT 59840 Geum Environmental Consulting, Inc. 307 State Street, P.O. Box 1956 Hamilton, MT 59840 DTM CONSULTING, INC. 211 North grand avenue, suite J Bozeman, mt 59715 Table of Contents 1.0 INTRODUCTION ............................................................................................................................ 3 1.1 PROJECT DESCRIPTION .................................................................................................................... 3 1.2 GOALS AND LIMITATIONS................................................................................................................ 3 1.3 DOCUMENT ORGANIZATION ............................................................................................................ 4 2.0 TECHNICAL APPROACH ............................................................................................................. 5 2.1 INTRODUCTION ............................................................................................................................... 5 2.2 SPATIAL DATA INVENTORY ............................................................................................................. 5 2.3 SUPPORTING REPORTS AND DOCUMENTS ......................................................................................... 6 2.4 EXPERT INPUT................................................................................................................................. 7 2.5 CRITERIA DEVELOPMENT ................................................................................................................ 7 2.6 DATA PREPARATION ....................................................................................................................... 8 2.7 GIS FRAMEWORK ........................................................................................................................... 8 3.0 SUBMODEL DESCRIPTIONS AND CRITERIA........................................................................... 9 3.1 EXISTING INFRASTRUCTURE SUBMODEL .......................................................................................... 9 3.1.1 Existing Infrastructure Submodel Description.......................................................................... 9 3.1.2 Existing Infrastructure Submodel Criteria Rationale.............................................................. 11 3.1.3 Existing Infrastructure Submodel Criteria ............................................................................. 13 3.2 WATER RESOURCES SUBMODEL .................................................................................................... 14 3.2.1 Water Resources Submodel Description ................................................................................ 14 3.2.2 Water Resources Submodel Criteria Rationale ...................................................................... 16 3.2.3 Water Resources Submodel Criteria...................................................................................... 16 3.3 WILDLIFE RESOURCES SUBMODEL................................................................................................. 17 3.3.1 Wildlife Resources Submodel Description.............................................................................. 17 3.3.2 Wildlife Resources Submodel Criteria Rationale.................................................................... 19 3.3.3 Wildlife Resources Submodel Criteria ................................................................................... 19 3.4 WORKING LANDS SUBMODEL ........................................................................................................ 21 3.4.1 Working Lands Submodel Description................................................................................... 21 3.4.2 Working Lands Submodel Criteria Rationale......................................................................... 23 3.4.3 Working Lands Submodel Criteria......................................................................................... 23 3.5 OPEN LANDS SUBMODEL............................................................................................................... 24 3.5.1 Open Lands Submodel Description........................................................................................ 24 3.5.2 Open Lands Submodel Criteria Rationale.............................................................................. 26 3.5.3 Open Lands Submodel Criteria ............................................................................................. 26 3.6 PUBLIC HEALTH AND SAFETY SUBMODEL ...................................................................................... 28 3.6.1 Public Health and Safety Submodel Description .................................................................... 28 3.6.2 Public Health and Safety Submodel Criteria Rationale .......................................................... 30 3.6.3 Public Health and Safety Submodel Criteria.......................................................................... 32 3.7 THE LAND SUITABILITY ANALYSIS (COMBINING SIX SUBMODELS INTO ONE FINAL MODEL) ........... 33 3.7.1 Reclassifying Submodels ....................................................................................................... 33 3.7.2 Combining Submodels........................................................................................................... 34 4.0 USE AND RECOMMENDATIONS............................................................................................... 36 4.1 THE LAND SUITABILITY ANALYSIS ................................................................................................ 36 4.2 USE IN THE COUNTYWIDE ZONING PROJECT ................................................................................... 36 4.3 RECOMMENDATIONS ..................................................................................................................... 36 4.4 GIS DATA..................................................................................................................................... 36 5.0 REFERENCES ............................................................................................................................... 37 Ravalli County LSA Report Page 1 of 72 June 2008 APPENDIX A – DATA DESCRIPTIONS ........................................................................................... 40 APPENDIX B – REPORT SUMMARIES ........................................................................................... 52 APPENDIX C – MEETING SUMMARIES......................................................................................... 58 APPENDIX D – DETAILED SUBMODEL CRITERIA ..................................................................... 64 Water Resources Submodel Criteria............................................................................................... 65 Wildlife Resources Submodel Criteria............................................................................................ 66 Working Lands Submodel Criteria................................................................................................. 67 Open Lands Submodel Criteria...................................................................................................... 69 APPENDIX E – MODELBUILDER SCHEMATICS AND DATA DESCRIPTIONS........................ 70 Ravalli County LSA Report Page 2 of 72 June 2008 1.0 Introduction 1.1 Project Description The Land Suitability Analysis (LSA) described in this document is a Geographic Information Systems (GIS)based tool for evaluating the relative suitability of land for development in Ravalli County, Montana. The purpose of this analysis is to support the development of baseline zoning in Ravalli County. The end product is a generalized map showing areas of the County that are more or less suitable for development. The resulting suitability map is not intended to be used at a sitespecific scale and does not constitute a zoning map. For purposes of this analysis, suitability can be defined in terms of physical limitations, existing regulatory restrictions, and the community goals expressed in the Ravalli County Growth Policy (Ravalli County 2002, rev. 2004). Physical limitations such as steep slopes, poorly drained soils or high risk of wildfire make the land less suitable for development. Features subject to existing regulatory restrictions, such as a mapped floodplain or wetland, also pose challenges to development. The goals in the Ravalli County Growth Policy were used as a guide in determining areas of the County that are important community resources, such as open space and wildlife habitat, as well as areas where development should be encouraged, such as near existing towns and infrastructure. The results of the LSA show areas within the County that are more or less suitable for development based on six categories: (1) existing infrastructure; (2) water resources; (3) wildlife resources; (4) working lands; (5) open lands; and (6) public health and safety. These categories are referred to as submodels. These six submodels were selected (1) to ensure that the LSA provides appropriate information to support decisions about zoning based on State