COLUMN ENGINEER'S NOTEBOOK At that time, energy and water were cheap and plentiful. No compelling reason existed to pump condensate all the way back to the plant. I was disturbed at the thought of all that wasted energy. As the design for the north entry proceeded, I began to formulate an idea. Why not recover heat from the condensate and use it for snow melting on the north sidewalk and the new entry plaza? I sketched up a system that would route steam condensate to a storage tank, then pump it to a heat exchanger, which would heat a glycol solution to use for snow melting. The tank would include a steam bundle as a backup heat source in case there was insuffi cient hot condensate available. This idea was quickly embraced by the City and we proceeded with the design (Figure 1 and Photo 4). The snowmelt would cover the north sidewalk, new stairs and ramp and the entry plaza (Photo 5). The accessible ramp is on the far left and is partially hidden by the concrete wall of the new plaza. The project turned out well and solved the problem of accumulated snow and ice at the new entry. It also allowed those with mobility concerns to use the main entrance. Lessons Learned We learned immediately after installation that education is critical for public sidewalks that incorporate snow melting. Just days after the project was complete, an employee in the City Architect's offi ce discovered a city signage crew was getting ready to cut into the new sidewalk to install signs. They were unaware that snowmelt pipe was embedded just below the surface of the sidewalk. The employee quickly stopped the crew, and the signs were changed to sit on the surface of the sidewalk (Photo 6). The City also had permanent markers affi xed to the sidewalk and entry plaza stating that piping is embedded in the concrete. Another lesson we took away is the importance of coordinating the snowmelt design with the architect and landscape architect. The exterior plaza and entry design involved numerous team members who needed to meet regularly to review and coordinate the design details. The system uses a moisture sensor and a temperature sensor to put the snowmelt system in operation. Since it takes some time to heat up the large mass of concrete and granite, the system was set to start any time moisture is present and the temperature nears freezing. The City indicated that the moisture sensor didn't work well. It was D E C E M B E R 2 0 2 1 ashrae.o rg ASHRAE JOURNAL 39 PHOTO 1 City Hall of Kansas City, Mo. PHOTO 2 Accessible entry door to the left of the garage door prior to upgrades. PHOTO 3 North entry in 2005.https://www.ashrae.org/