Sisters wrestles with density questions in council workshop

Sisters' leaders continue to wrestle with a fundamental question that will shape the city's future: How to preserve Sisters' semi-rural character while accommodating a predicted population explosion over the next few years.

City councilor Lon Kellstrom said at a workshop on Thursday that many small cities in Oregon do not prohibit developers from building only one or two houses on an acre. But the Sisters City Council voted in May to adopt a controversial ordinance that requires developers to build four to eight units per gross acre in new residential subdivisions and nine to 20 units per gross acre in multi-family zones.

Planning commissioners and developers urged the council to adopt a density of two to seven units per acre, which would allow for larger lots -- and likely more expensive neighborhoods.

Kellstrom, who has favored allowing developers to build at lower densities, suggested the character of Sisters might best be preserved if the city mandates a minimum lot size but does not require any set number of units per acre. Kellstrom referred to a list compiled by city staff, which shows the codes among other small cities in Oregon. According to that list, several cities mandate a minimum lot size but no density level.

In addition to requiring four to eight units per gross acre, the City of Sisters currently requires developers who build single-family homes in existing subdivisions to do so with a minimum lot size of 6,000 square feet.

"Just have a 6,000 square-foot minimum and pass that," Kellstrom said. "Other cities only have minimum lot sizes. It is a commonly used practice in smaller cities in the state."

According to the list compiled by city staff, the City of Brookings has no density code, but requires a minimum of 6,000 square-foot lots. Similarly, Gearhart requires a 10,000 square-foot lot, and Gladstone requires 5,000 square feet for certain residential zones.

But councilor John Rahm said that requiring a minimum number of houses per acre will be key in providing homes for all income levels.

City officials also indicated that a minimum density will be vital in curtailing the expansion of the city's urban growth boundaries, which, as it expands, cuts into more farm and forest land. A larger UGB will also cost the city more money for maintenance.

"If you are concerned about growth, you raise the bottom (density requirement) up to slow the growth of the UGB," Rahm said.

Kellstrom responded that the majority of the residents want a city with about two to five units per acre, so it is the council's duty to give them what they want.

"Do you mean the people in Park Place (a new, higher-density subdivision near the Sisters Industrial Park) do not want to live here?" responded interim city planner Brian Rankin.

Rankin emphasized the impact that density requirements will have on the amount of land to be added to the urban growth boundaries. Within the current city limits, 88 acres of land are available for residential development, Rankin said. Twenty-two of those acres are within the single-family residential district and 66 acres are within the multi-family district.

But when all of those parcels are developed, 30 to 35 percent of that land will be required to be used for open space, Rankin said.

Sisters' population is expected to quadruple in the next 20 years, according to the latest city population forecast. Based on income and population demographics, Rankin estimated that the city will need to provide 1,440 more residential units over the next 20 years, with half affordable to residents with jobs below the median income.

He said that with the existing density requirement of four to eight units per gross acre, the city will need to add 225 acres of land to the UGB to accommodate 1,440 units. If the code is lowered to two to seven units, it will need to add 352 acres.

Rankin said that a code with a wider density range would allow for less UGB expansion. For example, a code of two to 16 units per acre would only require an additional 158 acres to accommodate 1,440 units. But Rankin told the council that he predicts developers would average at a lower density range if given that freedom.