Setty: DCPS, Dunbar High School Modernization
New construction at an educational facility.
Engineering firm: Setty
2014 MEP Giants rank: 76
Project: DCPS, Dunbar High School Modernization
Address: Washington, D.C., U.S.
Building type: Educational facility
Project type: New construction
Engineering services: Automation/controls, electrical/power, fire/life safety, HVAC/mechanical, lighting, energy/sustainability, plumbing/piping, and other
Project timeline: 4/1/2010 to 3/31/2013
MEP/FP budget: $1,314,684
During design it was determined that there was not enough land area to accommodate 365 wells unless the existing school was completely demolished. This was not a viable option until the construction of the new school was fully completed. This posed a problem because there was no temporary facility adequate to house the students while the new school was being constructed. Also, permitting of the geothermal well field via the DC Department of the Environment (DDOE) was an extremely slow process.
As a result of these challenges Setty decided to split the geothermal well field into two phases, each with its own vault and distribution piping network. The first phase would encompass 166 wells, while the second phase would account for the remaining 199 wells. To further complicate matters, an old fuel oil storage tank that had leaked and contaminated a portion of the soil was discovered in the second phase. This development created more delays in the permitting process. Meanwhile, to get the new building ready for occupancy, phase 1 of the well field could not carry the full building load. So Setty designed a plate and frame heat exchanger, and valved and capped connections to allow for a temporary cooling tower during summer and a hot water boiler during winter and associated pumps that would be just enough to supplement the load for the Academic Wing. This allowed phase 1 of the geothermal well field to accommodate the rest of the building, which included the Administration Wing and the Multipurpose Wing. After further cost evaluation by the Dept. of General Services, it was determined that the heat exchanger and associated pumps were cost prohibitive. As a result, the design team decided that the only way it could operate the new building on a partial well field was to initiate load shedding of various parts of the building throughout the day. Units serving the Academic Wing would be brought online for a few hours while units serving the Multipurpose Wing would alternate run times. This approach was implemented and worked very well. The existing Dunbar High School has since been completely demolished, and phase 2 of the geothermal well field was completed in March 2013. Despite challenging obstacles, the project moved forward and the teachers, students, and community consider the new Dunbar High School a complete success.