Boulder City Council members unanimously approved a flood mitigation plan for South Boulder Creek late Tuesday night, but city leaders still face significant hurdles before the plan becomes a reality.
Council members’ approval means city staff will proceed with preliminary designs for the option known as Variant 1 100 year, which is a flood wall and detention pond on the land south of U.S. 36 and Table Mesa Drive. A portion of the land is owned by the University of Colorado Boulder and is known as CU South, and another portion is open space overseen by Open Space Board of Trustees.
Variant 1 100 year includes a 2,710-foot-long, 8.8-foot-tall flood wall along the edge of the property near U.S. 36 that would divert flood waters into a detention pond or dam large enough to hold 467 acre feet of water.
The project would also construct outlet pipes to discharge the floodwaters under U.S. 36 to the north. The entire project would have a 64-acre footprint.
“I am not sure the 100 year is the best solution, but it’s one we can afford better than we’re going to be able to afford the others and I think we need to live in the real world in that respect,” Council Member Mark Wallach said before the vote on Tuesday.
One of the most immediate challenges for Boulder city leaders is getting open space advocates on board with the plan.
While the Open Space Board of Trustees approved Variant 1 100 year, they did so with the caveat that the city must answer questions about whether upstream flood mitigation is feasible and how removing an existing levee on the land will impact flood mitigation and open space.
“OSBT will not vote on disposal (of the land to the city) until we have answer to these questions, in addition to others in our 2018 and 2019 recommendations to Council,” the trustees wrote in their motion.
Wallach described the board’s motion as “a Spartacus moment, where they’re almost in rebellion.”
“Their thoughts may not bear fruit, but if there’s a greater than zero probability that they might and provide some advantage to us, can we not get them some information and analysis, in a real time frame that’s useful to us?” Wallach asked at the Tuesday meeting.
Mayor Pro Tem Bob Yates’ motion to approve the Variant 1 100 year plan included direction for city staff “to analyze whether the upstream model would improve flood mitigation effectiveness, reduce costs, decrease environmental impacts or increase likelihoods of receiving applicable permits and permissions, providing that any such analysis not delay or impede staff’s further work on Variant 1 100 year.”
City council members must also come to an annexation agreement with CU Boulder, which owns a 308-acre parcel and is seeking to add the land to the city in order to access utilities.
CU Boulder plans to build housing, recreation fields and some academic buildings on the property and has agreed to give the city 80 acres of land for flood mitigation in exchange for the annexation.
CU Boulder has been with City Council through many iterations of flood mitigation, and the university is glad to see the city move forward with an option, said Frances Draper, senior strategic advisor for government and community engagement.
CU Boulder was initially opposed to Variant 1 because it largely cuts off access to the property, Draper said, but discussions with city leaders have led to the possibility of creating multiple access points to the property through Highway 93 and surrounding neighborhoods. There is not a formal agreement cementing that plan, Draper said.
CU Boulder was the subject of several biting public comments during the council’s public hearing, and Draper said the perception the the university is “holding the city over a barrel” is incorrect.
“We’ve steadily worked through this and the city has not been shy about asking for some serious benefits from CU, including 80 free acres,” she said. “We’re two public entities, we’ve got to both serve our charters and there is a happy compromise here if everyone will compromise to some level.”
The flood mitigation project is contingent on CU Boulder giving the city the land needed to complete it, and CU Boulder giving the city the land is tied to being annexed into the city.
“We thought it was a very positive outcome,” Draper said. “There’s a lot of work to be done to come to an annexation agreement.”