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This document summarizes the Residential and Commercial Buildable Land Inventory analysis for Dunes City Urban Growth Boundary. It addresses State Planning Goal 10, “To provide for the housing needs of citizens of the state.” Goal 10 and its administrative rules set out a process to estimate future housing needs and to analyze the supply and demand for residential land needed to accommodate future growth. Cities are required to provide a 20 year supply of residential and within their UGB at periodic review and legislative review, based on housing needs assessment.

This document addresses commercial land as far as updating the existing inventory. The focus of this document updates contains a housing needs analysis, an analysis of existing buildable land and a comparison of the supply of buildable residential land with forecasted housing demand. The housing need analysis forecasts housing demand to 2025. The supply analysis is based on buildable land as of 2005. In reviewing the future needs for land and the current supply within the urban growth boundary, it has been determined that there is not a 20-year supply of buildable residential land.

Buildable Lands Inventory

The future land needs of a community are determined by comparing the existing supply of land with the expected demand.  This chapter summarizes the methodology, assumptions, and results of Dunes City ’s Buildable Lands Inventory (BLI).  The inventory of buildable lands includes residential, commercial and open space land inside the city’s urban growth boundary (UGB).  Buildable land includes both vacant land and developed land that is likely to be redeveloped, and excludes land that is determined unbuildable by federal, state or local regulations.  The inventory is important for several reasons:

·        It helps determine the quantity and quality of vacant lands,

·        It helps identify how actual development patterns have been occurring, and

·        It helps determine the capacity of the UGB to accommodate residential and job growth.

The City of Dunes City has four plan designations.  The plan designations and associated zoning includes:

·        Commercial: Intended to provide convenience goods, personal services, and commercial goods to support the local economy and provide tourist commercial services. Accessible to Dunes City residents; Located on major street; should not be scattered, Not located on land with several development constraints; and avoid strip commercial development on Highway 101.

·        Residential: Intended to provide a variety of housing opportunities to meet housing needs. Single family units on 1 acre lots or larger; PUDS, including a variety of housing types and neighborhood commercial; Land already subdivided with lots smaller than one acre; Two-to-four family units, mobile homes and manufactured housing.

·        Open Space Lands: Those lands not suited for development because of natural development constraints or publicly owned lands designated as open space.

·        Public: Public and quasi public land, including part of the Boy Scout camp, state and county parks, and city facilities.

The methodology and assumptions for the Buildable Lands Inventory were reviewed by the Citizen Advisory Committee (CAC). A few adjustments were made to the original assumptions based on development trends. The Planning Commission reviewed the document and …..(will update after review).

There are some differences in the way residential and commercial lands were handled in the inventory process.  These differences are described in the methodology.  There are five general steps in the process that were used to estimate the amount of buildable land in Dunes City ’s UGB:

·        Update the land use and zoning in the computer geographic information system (GIS)

·        Determine gross vacant acres, including whole or partial tax lots

·        Determine constrained and unbuildable land

·        Determine percentage of acres needed for public facilities

·        Determine residential infill potential

·        Determine redevelopment potential

STEP 1            Update Land Use and Zoning in the GIS.

To update Dunes City ’s geographic data, the most recent land use data were plotted out and checked by staff, and field-checked by members of the CAC.  The field checking helped verify the actual use of the property, the location of newer roads and right-of-ways.  The geographic data for the city’s land use, zoning and plan designations were also updated at this time.

STEP 2            Determine Gross Vacant Acreage.

Gross vacant acres include all fully vacant tax lots, and the vacant portions of some partially developed lots.  Vacant lands include land uses that are coded as agricultural, timber, or vacant.  They do not contain any structures.  Partially vacant tax lots have improvements but also have enough undeveloped land to accommodate additional development.

Ø      Residential Land :  In some cases partially vacant lots were field-checked to determine the extent and location of the residential improvements.  The undeveloped portion of the lot was then added to the gross vacant acreage. When field checking was not practical, parcels over an acre in size were assigned one acre of residential use and the remainder assigned as vacant.

      In some cases the remaining acreage was less than one acre and was therefore removed from the gross vacant acreage since Dunes City requires a one acre minimum lot size for new development. This represents less than one percent about .3% (25 acres) of the gross vacant acres.

      Commercial: Partially vacant lots were field-checked to determine what, if any, portion of the tax lot should be assigned a vacant use code.  All improvements such as landscaped and paved areas were considered developed.

Gross Vacant Acres by Plan Designation

STEP 3            Determine Unbuildable and Constrained Lands.

Some lands are unbuildable outright, whereas others are constrained and potentially could be developed if the constraints were addressed.  The lands that are determined to be unbuildable are subtracted from the inventory.  The constrained lands are dealt with on a case by case basis.

Unbuildable Lands

Size: There are some parcels in the data file that are too small to be developed.  In most cases, these are “slivers” of land that result from data layers that do not match exactly.  For example, some plan designations may overlap onto a tiny portion of an adjacent tax lot of a different plan designation.  That overlapping piece will show up as a tiny parcel.

Floodways: The Flood Insurance Rate Map designates regulated floodways.  There were no areas identified within a floodway within Dunes City .

The following table summarizes the impact of the unbuildable lands on the inventory.

Unbuildable Vacant Acres by Plan Designation

Constrained Lands

Development of constrained land could affect the building cost, density, or other site-specific development factors.  State policy gives jurisdictions the right to decide what is unbuildable based on local development policies.  Dunes City ’s current policies allow development throughout the city.  However, there are several areas with development constraints.  Each constraint was discussed with the Citizen Advisory Committee.  The results of those discussions, and the resultant impact on the inventory, are included in this final draft.

The following describes how constraints were handled in the Buildable Lands Inventory:

The constraints identified for this study were:

• Flood Hazards
• Riparian Areas (shoreline)
• Delineated Wetlands from Local Wetland Inventory
• Slopes over 16%

Acres of constrained land include the total acres of all land containing any of the constraints identified. An area can include a single constraint or a combination of many constraints overlapping. Therefore, individual constrained land will not equal the sum of each individual constraint and its acres. Total acres where only one constraint was identified and the constraint's impact on the supply is discussed below.

Flood Hazards: The Flood Insurance Rate Map designates areas subject to a 1% or 100-year flood. Dunes City ’s Code of Ordinances regulates development in the floodplain through adoption by reference the most recent Flood Insurance Rate Maps.  Development in the flood hazard areas identified on FEMA maps must meet the requirements of floor elevation, anchoring, construction materials and methods, and utilities. Of the total 410 total acres identified as constrained (includes all constraints), 79 acres included floodplain with one or more constraints and 22 acres included only flood hazard for a total of 101 acres. Vacant land with floodplain only represents 2.5% of the gross vacant acres. The 22 acres where flood plain exits alone were not subtracted from gross vacant acres since the City allows development in the floodplain.

Ø      Wetlands: The Local Wetland Inventory completed in 2004 was used to determine the vacant land in the Dunes City UGB that falls within delineated wetlands.  Wetlands overlap with several of the constraints identified such as riparian area and 100 year flood zone –this accounted for 99 acres and wetlands on their own totaled 13 acres. In total there are 112 vacant acres with delineated wetlands.

Ø      Slope: Vacant land with slopes over16% was identified as a constraint to development. Development on slopes greater than 16% is permitted in Dunes City with documentation from a licensed Oregon Engineer which shows such development to be safe. Based on past development trends, the Citizen Advisory Committee estimated 60% of vacant sloped land can be expected to be developed. Of the 234 acres containing slopes and other constraints, 186 acres was identified as having slopes greater than 16% only. Of the 186 acres of sloped only land, 75 acres (40%) was subtracted from the inventory.

Availability of Services: Dunes City is not connected to city sewer or water and septic is dependant on lot size. The city requires a one acre minimum lot size to accommodate new septic and existing lots under an acre are permitted to be developed. Lot size has more impact on the inventory than availability of services. The impact of partially vacant acres on the inventory is discussed under infill and land less than one acre has already been subtracted from the inventory. Therefore, this constraint does not apply.

Constrained Vacant Acres by Plan Designation

NOTES: The percentages represent the percent of constrained vacant land within that plan designation.  For example, 22% of the vacant Residential land is constrained.

The following table summarizes the gross vacant buildable acres.  In total, approximately 289 acres were subtracted from the inventory to account for unbuildable lands and to address development constraint assumptions.

Gross Vacant Buildable Acres by Plan Designation