RMF's Stephen Pollard and Vance Nall Featured in the Fourth Quarter 2023 Issue of District Energy Magazine

How to modernize district systems on historic campuses? Tread lightly is the lesson

Projects at William & Mary and the University of Georgia honor venerable aspects of the past while building for a better future

By Stephen Pollard, Vance Nall, Jason Perry and Adam Witkowski

Cultural and historic aspects of campus architecture can add value and meaning to the college experience, particularly at institutions that have evolved over centuries and where preservation can strengthen the sense of campus community, deepen the quality of learning and enhance certain aesthetics that add prestige.

But as buildings age, student populations increase and infrastructure systems require updates to meet expectations, cultural and historical assets can also complicate the modernization process. District energy – as the two case studies in this article suggest – has emerged as an ideal solution on historic campuses, allowing for high-quality, efficient and reliable building systems without the challenges associated with unitary HVAC equipment – which is typically installed building by building and can be intrusive, loud and unsightly.

Planned properly and approached delicately, campus infrastructure modernization done right can reduce energy consumption and maintenance while protecting the integrity of historic buildings – all while simultaneously minimizing disruption and maximizing value.

And by bringing sensitivity and intention to the design of a district energy plant itself, modernization can be woven into the fabric of a campus in a way that respects and even expands on architectural and aesthetic traditions.

The projects described here are at the College of William & Mary and the University of Georgia, both of which have rich histories. Founded in 1693 at the height of British colonialism in North America, W&M is the second-oldest institution of higher learning in the U.S. In 1785, the University of Georgia became the first state-chartered public university in the new country. Each campus displays unique architectural beauty in its historic buildings that pose challenges related to maintenance, preservation and modernization.

While preserving cultural heritage is important, so too is ensuring that facilities contribute functionally and efficiently. As colleges and universities everywhere evolve to meet current and future needs, engineers are increasingly called to bring thoughtful approaches that deliver results but also respect campus grounds, often in ways that require an especially delicate approach. When it came time for W&M and UGA to upgrade their district energy plants and underground distribution piping networks, the universities brought on RMF Engineering Inc. to design the placement and construction of the new facilities and renovated systems.

MODERNIZING AT WILLIAM & MARY

Located in Williamsburg, Va., W&M is a cradle of American history and home to the oldest and longest-standing college building in the U.S., the Wren Building, erected in 1700. Today, W&M is a research university that reports significant growth in both the size of its campus and its student population, which is nearing 7,000 undergraduates – a 13% increase since 2011. Over the years, the campus energy generation and distribution systems have been expanded and modernized to accommodate growth. ultimately, however, W&M found itself juggling the demands of aged mechanical systems that were rapidly approaching the end of their useful lives, new requirements for utility redundancy, and projected campus growth requiring additional capacity.

In 2019, W&M commissioned a new district energy plant and distribution system. The West Utility Plant, centrally located between academic and residential buildings, uses modern equipment and distribution methods with 5,120 tons of cooling capacity, 60,000 MMBTU of heating capacity, and a backup generator sized to support three hot water generators, pumps, support equipment and code-required emergency components. Design elements utilize materials that complement campus consistent features such as heavy red bricks and pavers. Through a glass facade, the interior mechanical and electrical equipment can be seen from the outside, tastefully showcasing the modernization and subtly reminding passersby that W&M is working to improve system reliability, maximize energy efficiency and lower greenhouse gas emissions campuswide.

The plant is on a constrained site adjacent to Adair Hall and Ukrop Way, on what was previously a gravel parking lot. The location was selected due to its proximity to academic and residential building loads – and to incoming public utilities. The placement also put the building beside a highly trafficked roadway, making a cohesive architectural design paramount. The project architect collected and sampled design elements from noted existing campus buildings – elements that included horizontal ledgers, concrete-capped brick knee walls and Flemish bond brick walls. These were combined with more modern elements such as storefront glazing and perforated metal screening. The design began with watercolor sketches and advanced through simple line drawings to preconstruction renderings, with the Office of the University Architect providing feedback at every stage. The building, once complete, was certified LEED Gold.

The W&M project required thousands of feet of new low-temperature hot- and chilled-water distribution piping. Usually, roadways and sidewalks are avoided in utility upgrades because of the higher cost of construction and disruption to traffic. At W&M, however, roadways and sidewalks provided a clear pathway through mature trees and historically important artifacts and structure.
One major challenge was how to traverse a protected wetland adjacent to the West Plant. Multiple options were evaluated, including a trenchless crossing, open-cut trenching and suspending the piping from an existing bridge. While affected areas of the wetland could have been restored with soil protection and replacement plantings, the bridge option was selected to avoid such impacts entirely. Builders erected scaffolding beneath the bridge to provide a continuous level working surface. Campuswide, after the completion of piping installation, the project restored affected areas in part by using salvaged materials that matched existing colors and patterns.

AGGRESSIVE PHASE MANAGEMENT AT UGA

At the edge of downtown Athens, Ga., an arch installed in 1857 marks the entrance to UGA’s North campus. The campus holds immense historical value, especially in buildings that date back to the early 1800s. These include the Holmes-Hunter Academic Building, comprising Ivy Hall, built in 1835, and the Library Building, built in 1860 – which were combined in 1905 to create the version that exists today – and other landmarks like the Chapel and its beloved Chapel Bell, and Herty Field, the university’s first athletic venue.

The heating system for this part of campus has evolved over the years from local and regional steam boilers to campus steam distribution; the most recently updated system utilized low-pressure steam that originated from an on-site generation plant and ran through two pressure reduction points along the path to North Campus. Following a series of steam system planning studies, RMF developed a modernization plan to replace this with regional heating water systems.

The cooling systems for this part of UGA’s campus had already been modernized to chilled water, but the buildings were still served by unitary equipment that was nearing the end of its service life. Consequently, an extension of the campus district chilled water system was needed. With the further modernizing of infrastructure on North Campus came an opportunity to replace and upsize existing domestic water, electric and communications utilities. These improvements brought redundancy and reliability while helping enable a transition to lower-carbon energy sources in the oldest section of campus.

To minimize disruption, RMF distributed work across three phases involving an upgrade and extension of the North Campus chilled water system as well as the development of a regional heating water plant and distribution system.

The first phase was completed in 2021 and included the heating water distribution extension and routing of the underground utilities between Candler Hall, Meigs Hall and Moore Hall up to the west side of Herty Drive. This phase also connected Meigs and Moore Halls to the North Campus chilled water system, allowing for the removal of the noisy air-cooled chiller serving these two buildings, which house a mix of academic and office space. Domestic water and medium-voltage electrical systems were also installed for future use.

The project’s second phase was completed in the summer of 2022 and extended the heating water, chilled water and domestic water further north – connecting the Chapel and the New College building to campus chilled water and enabling the planned renovation of the Holmes-Hunter Academic Building. A total HVAC renovation of the Chapel was also completed in this phase, which enabled the transition to campus chilled water while requiring an interim steam to-heating water converter. Challenges in this phase involved coming up with a structural design for crossing under the shallow brick foundation of the Chapel. This phase provided the larger campuswide system with further redundancy and reliability.

Keeping the existing low-pressure steam system active during these two initial phases of utility construction required highly coordinated design and construction. Low-pressure steam was utilized for campus heat until the end of the spring semester in 2023, when it was shut down for construction of the regional heating water plant. The first two phases carried the heating water distribution into the building’s mechanical rooms, where it was left inactive until the final phase delivers heating water to the spaces.

The project’s final phase will be the development of the heating water regional plant in Candler Hall, for which RMF is providing design and construction administration. Medium pressure campus steam (45 PSIG) will generate 180 F water for service to the new regional heating water distribution system. The regional plant utilizes fully redundant heat exchangers and pumps to ensure reliability of the system and is sized to accommodate further extensions of the distribution system on North Campus and for a supply temperature setpoint reduction to 130F, allowing for the distribution system to accommodate future system upgrades utilizing lower grade heat sources.