The Daily Camera newspaper reports that residents voted 614-498 against the measure in a special week-long election that ended Tuesday evening.
The proposal would have allowed Lyons to lease between five and seven acres of the nearly 26-acre park to the Boulder County Housing Authority for a 66-unit housing complex.
About 200 houses in the town were badly damaged or destroyed in the September 2013 floods, about one-fifth of its housing stock.
Opponents argued that using a portion of the park to build rental units and private homes would have a big impact on the rest of the property.
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