1. Chittenden County Land Use - Transportation Decision Support System http://www.ccmpo.org/planning/dss November 19, 2003 Chittenden County Metropolitan Planning Organization Chittenden County Regional Planning Commission Vermont Agency of Transportation

2. Presentation Overview Why use the DSS? Use of DSS within Planning Processes Structure of Decision Support System (DSS) Software Current Test Results

3. What is the Land Use-Transportation Decision Support System (DSS)? A free-standing, GIS-embedded software that examines the interrelationships of transportation and land use, and provides outputs in support of local and regional planning processes. The outputs have been designed to assist stakeholders and decision-makers in: 1.Assessing Existing Conditions 2.Creating Plans 3.Implementing Plans 4.Achieving Plans

4. Why DSS? Better integration of transportation model with more detailed land use modeling capabilities. Tool for examining influences of large “regionally significant” projects. Visual and quantitative information to assist policy boards in making decisions. Output informs planning process.

5. Step #1 Identify Values Step #5 Develop Alternative Plans Step #2 Determine Indicators Step #4 Evaluate Current Conditions Step #6 Evaluate Alternative Plans Step #3 Develop Assumptions Step #7 Adopt Desired Plan In Support of Planning

6. DSS Software Overview Snapshot Mode –Parcel Based Forecast Mode –Resizable Grid (50-200 acres) 200 acre grid Snapshot results screen

7. “Snapshot” Analysis Static, Parcel based analysis Useful in examining specific development proposals Does not automatically forecast future development Training for Local Planners completed on July 24, 2002 Pilot studies ongoing in Shelburne and Charlotte

8. Forecast Analysis Forecasts location of future housing and employment and associated travel demand Useful in examining projects with Regional Impacts

9. Required Inputs for DSS Forecast Mode

12. Chittenden County Residential Zoning

13. Chittenden County Non-Residential Zoning

15. Forecast Accessibility The “Accessibility” is calculated for each grid cell Accessibility is an objective measurement that describes the convenience and efficiency of traveling between locations Accessibility is the inverse of travel time between locations factored to reflect: –The number of origins and destinations –The grid cell’s proximity to roadways

16. TAZ-Level Accessibility

17. Smoothed TAZ-level Accessibility

18. Distance to Local Streets

19. Factored Grid-level Accessibility

20. Forecast Attractiveness The “Attractiveness” is calculated for each grid cell Each cell’s Accessibility measure is factored to reflect development incentives and/or disincentives

21. Septic Soil and Municipal Sewer Parameters NOTE: These data reflect the 1996 on-site rules Potential Attractiveness Factors Municipal Sewer Service Area 105% Conventional Septic 100% Mound System 95% Unsuitable85%

22. Housing and Employment Allocation Based upon the final Attractiveness “scores”, all developable cells are grouped into 10 deciles The DSS then assigns 50% of the new housing and employment into first decile, 25% into second decile, 12.5% into third decile, etc. If a decile cannot absorb the appropriated growth, then the excess development goes into the next decile Within each decile, the cells are randomly chosen

23. DSS Forecast Hypothetical Tests Two Rounds of Testing Round 1 4 Scenarios: 1A - Base land use and transportation network 1B - Increased density allowances throughout Region 1C - Five-lane Route 7 1D - Increased density allowances and Five-lane Route 7 Round 2 4 Scenarios 2A – Base land use and transportation network 2B – Base land use and express bus service to Jericho & new Milton interchange 2C – TOD land use and Base transportation network 2D – TOD land use and express bus service to Jericho & new Milton interchange

24. Single-Family Residential Hypothetical Testing Scenario 1A Base Land Use and Base Transportation Network Accessibility to Employment (2024) Hypothetical Testing Scenario 1B Extreme Land Use and Base Transportation Network

25. Single-Family Residential Hypothetical Testing Scenario 1A Base Land Use and Base Transportation Network Attractiveness (2024) Hypothetical Testing Scenario 1B Extreme Land Use and Base Transportation Network

26. Volume to Capacity Ratio Hypothetical Testing Scenario 1A Base Land Use and Base Transportation Network Hypothetical Testing Scenario 1B Extreme Land Use and Base Transportation Network

27. Comparison of Housing Growth Allocation Base Case vs. Extreme Scenarios

28. Comparison of Employment Growth Allocation Base Case vs. Extreme Scenarios

29. General Conclusions Land use policies have a stronge influence on Accessibility and Attractiveness Influence of land use policies dampened by the influence of transportation improvements Transportation improvements in the urban/suburban core of the County create more accessibility in the Transition and Rural Planning Areas Existing high allowances for non-residential growth are only slightly impacted by changes to transportation system and/or land use policies Current land use policies can not accommodate anticipated housing demand

30. Steering Committee Recommendation Recommended to CCMPO/CCRPC Boards the DSS software is an appropriate tool to assist in local and regional land use and transportation planning processes.

31. Next Steps Model development is an ongoing process. DSS provides better information for planning. DSS provides the best analysis possible to date, but will not predict an absolute future.