HILLSIDE DEVELOPMENT
U.S. VIRGIN ISLANDS AND PUERTO RICO
THE TRAGEDY OF THE COMMONS
Low-density land use, rather than high-density uses, is not an effective regulatory zoning mandate to decrease the development impacts on steep slopes and sensitive coastal zones typical of the Virgin Islands and most of Puerto Rico. Even if low-density residential is conventionally considered the best or only use for suburban areas without public services, the cumulative effects of scattered single-family housing on a sensitive coastal environment like ours are difficult to predict and can be dramatic.
Development can be deleterious to our shallow bedrock and septic tank unsuitable soils, with potential impacts on soil contamination and erosion during construction. Development also changes the surface of the land by replacing natural cover and native vegetation with rooftops, roads, driveways, compacted fill, and parking lots. These hard surfaces are impermeable to rainfall and change the site’s hydrology considerably by preventing the infiltration of water into the soil, irreversibly altering the groundwater recharge areas and increasing the frequency and volume of stormwater runoff that flows downhill toward the ocean.
Most importantly, land clearance on steep slopes eliminates the vegetation that helps hold our shallow topsoil in place. The exposed topsoil, which took thousands of years to produce, is washed away in minutes in a storm along with the biological systems that helped to produce it, eliminating forever the potential for soil to perpetuate itself. This means that, in the process of losing our soil during storms as “non-point source pollution” into the ocean, we could be on the path to desertification both above and below sea level, following precisely the same fate of other islands across the world with older cultures and history than ours.
In fact, the sediment discharged into the ocean is adding to the warming of the ocean water and progressively killing our coral reefs and seagrass beds, whose health is fundamental for sustaining our marine life and the production of white sand for our world-famous beaches. With fish, coral, and beaches disappearing, our local fishing industry and tourism industry could eventually disappear. In the end, the question of development on environmentally sensitive areas is not a technical problem or political choice/decision. It is not a matter of landownership rights, individual concerns, or personal aesthetics. It is a collective, public issue—a tragedy of the commons—that needs to be addressed seriously in the future at all regulatory, planning, and implementation levels.
STEEP SLOPES
For residential development on steep slopes (40% to 65%), we typically provide site planning along with concept design for the proposed buildings, to help architects place buildings and roads minimizing earthwork and soil loss. Our early developer clients often came with preconceived home types designed in the US mainland. They envisioned design programs and densities that were allowed in the local zoning code, but high when considering our steep slopes, the need for utilities and road infrastructure, and the desire to space the buildings far enough to provide privacy and an ocean view to each unit.
Since site features are different in many areas of each project site, we typically break up the building mass, stepping its components into the topography by terracing them in the proposed landscape and amenities. The various building types have often been created from a “kit of parts” to choose from, and could be rotated, opened up, and disengaged according to existing trees to protect or rock outcroppings. We often had a narrow, small building type on three stories, that could easily fit in the steeper and narrow areas of the site development.
Another planning strategy we have used is to propose a “group dwelling permit” type of project rather than traditional subdivisions. By designing conservation easements in the steeper or more sensitive areas, we then surveyed all the most important trees and placed potential building footprints and other programmatic elements BEFORE designing the layout of access and service roads. This created a more organic design, where repetitive lots were not arbitrarily imposed on the topography to follow an arbitrary access road that only looked good on paper.
Many of our clients wanted to use for inspiration the compact, high-density villages of our pre-industrialized European counterparts, and the local island vernacular architecture. They expected this would please the Historic Commission, the community, and facilitate the development approval process. That is why most of the architectural concepts in our projects were traditional in style or scale, using hip roofs and smaller footprints rather than modern, open layouts. However, those European precedents, as said above, are still difficult to work with in our current lifestyle and automobile-oriented culture. It is not the style of buildings or the precedent that matters: it is the fact that hillside development cannot be drawn on paper as if it were on flat land: the site, the ridgelines, the natural swales, the soil, and trees that took often centuries to establish have precedence over everything else.
DESIGN STANDARDS AND GUIDELINES
To facilitate the approval process and the management of teams of architects and engineers in large projects, we prepare Design Standards for Development and Construction or Guidelines for both public and private projects, as well as Covenants, Conditions, and Restrictions (CC&Rs). These tools guide project design decisions and construction, enforcing smaller, detached building units in each residential compound, not necessarily traditional in style, located at different grades to lower the impact, connected by outdoor semi-covered spaces, and incorporating important existing trees in the intermediate spaces between building units.
