Smithsonian Environmental Research Center (SERC) Green Village Site Infrastructure

The Smithsonian Environmental Research Center (SERC) provides science-based knowledge to meet the environmental challenges of the 21st century. SERC leads research on coastal ecosystems-where the land meets the sea-to inform real-world decisions for wise policies, best business practices and a sustainable planet.

SERC research is urgent. The world’s coastal zones are home to more than 70 percent of the global population and experience intense economic activity. The rate of environmental change is accelerating at an alarming rate. Since its creation in 1965, SERC has been conducting peer-reviewed research to understand the causes and consequences of rapid change in the Chesapeake Bay and around the world.

To provide easy access for faculty, visiting scientists and students to SERC’s research and education facilities, additional housing was required. The Green Village Infrastructure project laid the groundwork for the construction of six cottages that can provide short term and long-term housing.

Our scope of work consisted of demolition of existing site elements such as asphalt pavement, underground electrical conduits and manholes, and brush clearing as well as the installation of new infrastructure improvements. This included excavating and grading of building pads and roadways, asphalt paving, pavement markings, streetlights, storm drain, trench drains, electrical conduit with associated handholes & manholes, communications conduits with associated handholes, domestic water piping, reclaimed water piping, dry fire department connection piping, sewer piping and manholes.

While the overall project was a success, it wasn’t without its fair share of challenges. Design build changes, weather and site constraints all added to the difficulty of construction.

The civil drawings that were issued for the project were considered only 90% complete. It was up to the general contractor to complete the design. The general contractor ultimately ended up using a hybrid design build approach using the 90% complete drawings. While this method was very economical for the general contractor, it put a lot of additional responsibility on Ferguson Trenching. Before any of the proposed utilities could be installed, we had to hire a private utility locator to map all the existing utilities. We then took that information and hydro excavated all existing utilities to determine size and depth. This information was then plotted against the 90% drawings to look for any issues with the proposed utilities. Right off the bat storm drain lines had to be moved and lowered to avoid existing power and communication conduits that were in the way. Reclaimed water lines were re-routed to avoid a potential issue with an existing communication conduit, and we even re-designed some of the proposed sanitary sewer services to avoid a time-consuming deep installation. The hybrid design build approach put more responsibilities on Ferguson Trenching at the beginning of the project but allowed the project to continue unabated. Under normal circumstances when unforeseen conditions are discovered, work comes to a grinding halt, the engineer must redesign the work around the unforeseen condition and depending on the project location the local municipality may need to review and approve the changes. This process can take anywhere from a few days to a few weeks. All the while the contractor is at a standstill. The hybrid design build concept was much more streamlined and allowed Ferguson Trenching to present solutions to issues that arose and get approval from the general contractor and SERC within hours.

Weather can be an issue on any construction project. It can affect the materials being used and it can lead to the rescheduling of tasks which can disrupt the overall schedule of a project. The SERC Green Village Infrastructure project was designed to be built into a hillside. While the construction of the cottages benefited from their placement in the hillside, it made the initial site work more difficult. Given that the project was released in early Fall of 2021 the site work portion of the project would have to be constructed during the coldest and wettest months of the year. When it rained, obviously everything ran downhill and onto our site. There wasn’t enough room between the limit of disturbance and the proposed cottages to create a run-off berm around us. We had to accept the water onto our site. Once it was on our site, we were able to divert it to constructed sediment control devices, but the amount of water that came down the hill usually cost us a minimum of a day to dry out the site after a rain event. It was critical to take advantage of dry weather when we had it. Crews worked many Saturdays to complete the sitework as quickly as possible and ready the building pads for the cottages. Once the cottage foundations were poured and the foundation drains were installed, the rain coming off the hill was easily handled by the foundation drains.

Vehicle access to the site was limited to a single road into the project. This wasn’t a problem when we were the only contractor on the project. Unfortunately, that didn’t last long, and the schedule dictated that at points multiple contractors would need to be on the site at the same time. Since most if not all our work was involved in the actual road into the project, it was imperative that we communicated our needs with the general contractor. Weekly subcontractor meetings would determine who needed access and to what parts of the project. Constant communication between the general contractor and the subcontractors allowed multiple contractors to work amicably on site at the same time. We also knew this might be an issue going into the project. By front loading our schedule with work in the constrained areas, we were able to work in other areas of the site when we knew congestion was going to be a problem. The general contractor thanked Ferguson Trenching more than once for being a “team” player and working well with our fellow subcontractors.