One thousand acres of agricultural land the city of Boulder wanted for open space has been left in private hands because falling sales tax revenue and chaotic credit markets made it a bad time to sell bonds.

In the meantime, the sales tax revenues have continued to decline, while sellers continue to ask top dollar for vacant land.

The Boulder City Council and the Open Space and Mountain Parks Board of Trustees will meet Tuesday in a rare joint session to discuss how to set priorities and move ahead in a climate challenging to open space purchases.

Since 1967, when voters first approved a sales tax dedicated to open space, the city has purchased more than 45,000 acres from more than 300 owners.

The most recent open space acquisition plan identifies almost 8,000 acres of potential open space, ranging from farms and ranches to critical wildlife habitat and key trail connections. Since 2005, the city has purchased 2,085 acres of that at a cost of $38 million.

The city has another $38 million in bonding authorization to purchase more open space under the plan, but it hasn't been able to move ahead with any purchases since mid-2008 when the city backed off plans to sell bonds in a chaotic credit market.

With no improvement in sales tax revenues this summer, the city let the contract on one property expire and put negotiations for three others on hold, meaning 1,000 acres of land remained in private hands instead of becoming public open space, according to a city memo on open space issues.

Ann Goodhart, division manager for real estate services for Open Space and Mountain Parks, said very few properties are on the market now, and those that are, are over-priced, in the city's view.

"Sellers have not adjusted their expectations to reflect market conditions," Goodhart said.

The upside for the city is that its inability to buy land now doesn't mean it's missing out on great deals.

"Clearly, there was a setback," Boulder Mayor Matt Appelbaum said. "It may ultimately be in our favor if property values start to reflect what we see as the new economic reality."

One question before the city is how to prioritize purchases when there isn't enough money to buy all the designated land. At current land prices, it would take $100 million to purchase the remaining 5,815 acres, Goodhart said.

City Councilwoman Crystal Gray, who served five years on the Open Space board, said properties that fill critical gaps in existing open space are key, as are lands in the so-called Northern Tier, between North Foothills Highway and North 63rd Street.

She said there's also a lot of interest in preserving agricultural lands and leasing them back to small-scale farmers, a move that brings in revenue and reduces maintenance costs.

Appelbaum said lands in the Northern Tier are more of a county responsibility. He sees preserving critical habitat and filling gaps in trails and riparian corridors as top priorities.

Gray said it's important for the city to work with state lottery-funded Great Outdoors Colorado as it develops a new strategic plan. The more Boulder's priorities line up with GOCO's priorities, the more grant funding the city can take advantage of.

Ultimately, though, purchasing open space depends on willing sellers.

"When an owner wants to sell or offer a conservation easement, you need the flexibility to act," Gray said. "Sometimes, your best laid plans need to change to seize an opportunity."

Contact Camera Staff Writer Erica Meltzer at 303-473-1355 or meltzere@dailycamera.com.