White Rock Elementary, enhanced flood plain analysis. Source: Perkins+Will

White Rock Elementary’s building expansion, expected to open in August of 2018, hit a snag this month when architects and engineers working on the project learned that more of the expanded campus will rest in flood plain than previously thought. About half of the construction and renovation can proceed, but part of the project must be delayed.

At a meeting of the Project Planning Committee Tuesday night at the school, architects Daniel Day and David McMillin of Perkins+Will revealed the unexpected flood plain issues and the remediation measures planned to keep the project moving forward.

“We know that this creates a problem no one could have planned for,” explained Day. “It’s not likely we’ll be able to finish all of the project by fall of 2018.”

The WRE playground was known to sit in the flood plain, and construction had been designed to account for possible flood conditions, but Halff Associates, engineering the project, noted that the flood plain map was developed in 2007 by FEMA using outdated techniques. They commissioned a more sophisticated study resulting in the rendering above, with blue representing water inching closer to WRE facilities in a 100-year flood than previously predicted.

The new plan of action is two-pronged: to proceed with work not in the new flood plain as planned, beginning in October, and request a fill permit to lift areas which are. Underground storage tanks will also be installed to collect rain water, which will slowly be released into the McCree Branch behind the school.

Planners admit the remediation will add time and cost to the expansion.

Obtaining a fill permit from the City of Dallas’ Trinity Watershed Management office typically takes 3-6 months, then the city council must approve the application. FEMA must then sign off before the city can issue a building permit. During that process, though, a building permit can be obtained and construction can proceed for the rest of the project (shown in pink on the drawing below).

Construction at WRE is necessary due to the “regreening” of the neighborhood, with young families purchasing homes owned by empty nesters and filling a school once considered underutilized. Construction or renovation of about 46 classrooms can be completed by August 2018 – a net addition of 6 – but that isn’t enough to handle the influx of neighborhood kids. A new library, administration wing, academic courtyard, music rooms and art room will be finished but not the cafeteria, so administrators are considering leaving the old cafeteria open or bringing in catered lunches. A required storm shelter, big enough to hold all students and staff, will also be delayed.

“We have hit a bump in the road,” said Day, “but optimistically we want to have it done for the spring semester of 2019.”

After the meeting, timid hands lifted to ask, “What does all that blue [water] mean for my home? Will my house flood?”

There was a twitter of nervous laughter.

“This is just if it keeps raining and raining and raining,” assured McMillin. “It won’t spill out there unless it has nowhere else to go. This is a model of worst case, but we design against the worst case.”

“This is the last frame of a flood video,” agreed Day. “A 100-year flood is a 1% chance.”

More nervous laughter.

The first order of business is a public hearing today/Thursday at 1:30 p.m. of the City Plan Commission for submission of the revised planned development – the plan to expand the school. This is unrelated to flood plain, but instead involves issues such as traffic management, square footage and design.

Lee Walker, WRE principal and chair of the planning committee, will keep the community updated on the WRE website here. You can see renderings of the finished WRE project by Perkins+Will here.

White Rock Elementary expansion: Sections in pink can move forward, sections in blue will be delayed. Source: Perkins+Will