San Joaquin Valley Blueprint Residential Density Definition. Nathaniel E. Roth Information Center for the Environment UC Davis Michael C. McCoy Urban Land Use and Transportation Center UC Davis John Wright, Chair SJV Blueprint – Valley Planners Work Group Barbara Steck Fresno Council of Governments (Note: while this does a reasonable job of describing our thoughts on density as it applies to the densities derived from UPlan, it grossly oversimplifies a very complex process.) The densities used within UPlan and as expressed within the San Joaquin Valley Blueprint are a mixture of gross and net densities. This document is intended to clarify what is and is not included within the density calculations and to provide some examples of how these densities can be compared. These densities are intended to represent density at a scale equivalent to a general plan. It is important to note that we have defined this density to be the density of residential units that can be ascribed to the residential portion of an urbanized area. We are not including rural units that are developed independent of urban or suburban infrastructure. These units must be dealt with separately from urban units. Most simply described, the density includes the units themselves, the lots they are on and infrastructure that directly supports the units. This includes the entirety of the parcel that the unit is situated on, the residential streets that provide access to it, landscaping or small parks less than 2 acres in size, and utility infrastructure space for the neighborhood. It does not include larger parks, schools, drainage basins or components of the transportation infrastructure that services more than the local residential development. Commercial space is also not included. See Example 1 for a residential only development example. The two acre threshold on park size is intended to replicate the size at which a park starts to provide service to more than the immediate neighborhood. To conform to this intent, smaller parks that are included only as a feature for the neighborhood should be included as should other infrastructure dedicated exclusively to the neighborhood. Drainage basins and other infrastructure should be omitted if they provide drainage service to more than the immediately adjacent residential units. All commercial, industrial, economic service or regional transportation infrastructure space should be left out of these calculations. Neither the acreage nor the building footprints/units need to be considered as part of the residential density calculation. However, space dedicated to transportation infrastructure that directly supports the residential neighborhood may be included. This is assumed to be of a size limited to a small bus shelter, not a larger light rail station or bus depot. Roads that serve the residential units directly should be included in the area. Roads that form the perimeter of the neighborhood should be considered on a case by case basis. If the perimeter road permits has driveways for individual houses, then it would be appropriate to include half of the road area. If the road does not provide individual vehicle access to the housing units then it should be considered part of the regional infrastructure. Applying this definition becomes more difficult when working in communities with mixed use. The portion of mixed use that should be included in this calculation is only that devoted to the residential component. This means that the footprint of the residential space and any parking that would not otherwise exist without the residential units. See Example 2 for an example that includes commercial, mixed use, large parks and schools. Example 1. A developer is proposing a project to be built on 10 acres. There will be 2 acres of residential streets, 1 acre of park. The remaining 7 acres well be 25 units on 0.2 acre parcels each and 40 apartment units on the remaining 2 acres. This would produce 65 units for the 10 acre project or a density of 6.5 units per acre. Land use Single Family Dwellings@ 5 du/ac Apartments @ 20du/ac Residential Streets Park Total Density Acres 5 2 2 1 10 65/10 = 6.5 du/Ac Unit total 25 40 0 0 65 Include? Y Y Y Y Example 2. A developer is proposing a larger development on 1000 acres. 350 acres will be commercial space including parking. Another 50 acres will be mixed use with ten units per acre; parking for both the commercial and residential is shared with the remainder of the commercial space. There will also be 100 acres with 2000 apartments/condominiums, 200 acres with detached houses on 1/8th acre parcels, 100 acres of units on 1/5th acre parcels, 2 10 acre elementary/ junior high schools, and one 50 acre high school and 20 acres of park space larger than 2 acres, and 10 acres of parks less than 2 acres in size and 80 acres of residential road right of way and 20 acres of drainage basin. This gives us 2000 apartment /condominiums, 1600 single family units, and 500 units in the mixed use or a total of 3100 units. There are 50 acres of mixed use, 100 acres of apartments/condominiums, 200 acres of detached units, and 80 acres of residential roads, 10 acres of parks less than 2 acres in size or 440 acres of space associated with the residences. 4600 units/540 acres gives us a density of 7 units per acre. Land use Commercial Mixed Use (Residential Footprint) Single Family Dwellings @ 8 du/ac Single Family Dwellings@ 5 du/ac Apartments @ 20du/ac Residential Streets Schools Park > 2ac Parks < 2ac each Drainage Basin Total included Density Acres Unit total 350 0 50 500 200 1600 100 500 100 2000 80 0 70 0 20 0 10 0 20 0 540 4600 4600/540 = 8.5 du/Ac Include? N Y Y Y Y Y N N Y N