Technical Report

McKinleyville Community Planning Area Residential Development Analysis

Humboldt County is currently engaged in the process of updating their comprehensive land-use plan. This General Plan update will play a large role in determining how the county will develop in the next twenty-five years. This study was conducted in order to better understand how alternative residential development scenarios will affect the future of the county by the year 2025. For illustrative purposes, one part of the county - the McKinleyville Community Planning Area (CPA) - was chosen for analysis. The McKinleyville CPA was chosen because it is the largest unincorporated community and the fastest growing area in the county. Between 1980 and 2000, the population of the McKinleyville CPA nearly doubled from 7,765 to 13,599 residents. According to California Department of Finance population projections, the McKinleyville CPA is expected to continue to attract the highest rate of population growth in the county for the next few decades. When planning for new growth, one of the most important factors land use planners must take into account is the density at which residential development will take place. Developing at lower densities in primarily urbanized areas will necessitate the construction of more homes in the open spaces and agricultural lands surrounding these urbanized areas. The focus of this analysis is therefore a quantitative and visual assessment of various development options in the McKinleyville CPA. The computer models and simulations used in this analysis were generated using the computer software package ArcGIS© 9.1 in conjunction with the CommunityViz® extension. This software package allows for a powerful quantitative analysis of various development scenarios and the generation of advanced realistic looking 3-Dimensional Models to allow for visualization. The purpose of this analysis is not to recommend a particular scenario for how population growth and development should occur in McKinleyville in the next few decades. Rather, it is to illustrate the implications of various assumptions and hypothetical planning decisions and to demonstrate the potential that the CommunityViz® modeling software has to assist planners, policy makers, and the public in making more-informed decisions involving future development patterns in McKinleyville and throughout Humboldt County. We examine six hypothetical but plausible scenarios for this analysis. These scenarios represent a reasonable range of development options. Each scenario models residential development at a specific density in areas where considerable urban development already exists the McKinleyville Urban Development Area (UDA) and Urban Expansion Area (UEA), and subsequently demonstrates how development at these densities will impact: • The character of the remaining undeveloped land in McKinleyville. • The capacity of these areas (the UDA and UEA) to accommodate the projected population growth by the year 2025. • The number of homes and the density at which development would need to occur in the open spaces and agricultural lands in the remainder of the CPA in order to fully accommodate the 2025 projected population growth. The results of the analysis indicate that in order to accommodate the projected population growth by the year 2025 for McKinleyville entirely within the Urban Development Area (UDA), development in this zone would need to occur at a density of 7.9 dwelling units per acre on vacant, residentially zoned parcels (and parcels known to be considered for development). Under this scenario, parcels with homes already existing on them would not need to be developed further, nor would any additional development be required in the UEA or the remaining CPA in order to accommodate the projected population growth by the year 2025. As the density at which development occurs in the UDA and UEA decreases, the number of new homes required in the remainder of the CPA increases proportionately. Conversely, developing at densities greater than 7.9 dwelling units per acre in the UDA ensures a surplus of vacant, residentially zoned parcels within the UDA, which would then be available to accommodate population growth beyond the year 2025. Use of the CommunityViz® software package for this analysis provides a transparent method for analyzing various growth and development scenarios. Although every effort has been made to provide detail and specificity about the methods and data used, a model is by its very nature a representation of reality and will not always be in accordance with reality itself. If our use of certain data, methods, and assumptions is disputed by readers and reviewers of this report, we would like to take that information into consideration, and modify the computer model accordingly. It is our hope that we will be able to use the software to work with planners, policy-makers, and interested groups and individuals to illustrate the implications of different assumptions and hypothetical planning decisions. Thus, we hope that the results presented here will lead to future productive discussions on how to balance the need to accommodate future population growth with the desire to provide more affordable housing opportunities for existing and future residents and the desire to protect the rural landscape qualities that make McKinleyville and the rest of Humboldt County such a special place.