Coastal Buffer Zones

Article by: Kate Venturini, of the URI Outreach Center

Buffer zones between development and shoreline habitat are attempted in many states, but rarely work well enough to protect the ecosystem. Laws and enforcement vary between communities, as do development histories and how people interact with the environment. Realizing this dilemma, land developers are finding common solutions to invigorate buffers across the country by turning to ecology. Relying on native plants to distance fragile coastal shores from the impact of human development does more than obey a zoning laws. Growing healthy native buffers gives coastal habitat a true shot at survival and regeneration. The Native Plant Design Manual offers a new strategies to design rich coastal buffers. The Manual was created for a New England coastal climate, though the paradigm shifting approach presented is transferable to any ecosystem.

I. The Native Plant Design Manual

The Native Plant Design Manual presents a unique approach to landscape management that allows homeowners and landscape professionals to significantly improve environmental conditions in suburban areas while maintaining landscape use and aesthetics. The manual outlines an integrated, step-by-step process that considers the interactions between the natural, built and social elements of the landscape.

The Native Plant Design Manual was written by the University of Rhode Island Outreach Center (the Center) under contract with the Rhode Island Coastal Resources Management Council (CRMC), the agency charged with regulating the state’s coastal environment through the issuance of permits for work. It was commissioned as a regulatory tool to provide guidance to green industry professionals working in the Greenwich Bay area of Rhode Island.

The manual integrates the processes of Site Inventory (Chapter 2), Action Plan and Bubble Diagram Development (Chapter 3), Native Landscape Design (Chapter 4), LID Practice Design and Installation for Stormwater Management (Chapter 5), Native Plant System Design (Chapter 6) and Sustainable Site Preparation, Installation and Maintenance Practices (Chapter 7) to reduce land-derived impacts on water quality and habitat loss through the implementation of Low Impact Development (LID) practices and Native Plant Systems.

II. Coastal Regulations: A Paradigm Shift

Greenwich Bay is a highly-developed, productive estuary within Narragansett Bay that provides vital shellfish habitat, shoreline access, boating opportunities, scenic views, and historic significance to the citizens of Rhode Island. Residents, marinas, yacht clubs, shellfishing operations, restaurants, and other commercial enterprises depend on a healthy bay. Greenwich Bay is bordered by some of the most developed communities in Rhode Island, and is also plagued by the effects of a high level of impervious cover, including the generation of stormwater runoff that threatens the water quality needed to support the use of the estuary.

In the past, homeowners living within the Greenwich Bay area have been required to preserve intact vegetated coastal buffers and, where necessary, restore buffers that have been disturbed. In theory, vegetated coastal buffers provide shoreline habitat for wildlife and act as “buffer zones” between high intensity land-based activities and the fragile ecosystem of Greenwich Bay. However, in practice, the benefits of buffers are rarely achieved for reasons including:

– a high degree of development pre-dating the CRMC coastal buffer zone program;
– a lack of natural vegetation along the shoreline and proliferation of lawn areas;
– small residential lot sizes that cannot accommodate the CRMC-required coastal buffer and setback requirements; and
– high thresholds for activities triggering the CRMC coastal buffer requirements..
The Native Plant Design Manual has been developed to offer an alternative to the traditional buffer requirement. The approach offers trade-offs to property owners to meet guidelines for their landscape. Instead of following vegetated coastal buffer regulations which require standard buffer widths based on lot size, homeowners now have the option of incorporating Low Impact Development (LID) practices (e.g. rain gardens, infiltration trenches, dry wells) and Native Plant Systems (designed plant systems composed of native, layered vegetation with high habitat value) to manage stormwater on-site and create wildlife habitat, respectively.

Professional Certification

Landscape professionals interested in becoming certified as a Greenwich Bay “Coastal Landscape Manager” (CLM) will be required to attend a certification training offered annually at URI. Only those professionals certified as Greenwich Bay CLM’s will be permitted to conduct landscape management in the Greenwich Bay area.
This new regulatory tradeoff will reduce and, in some cases, eliminate the required width and size of the vegetated buffer along the coastline. CRMC hopes that this innovative approach will contribute to meeting the aesthetic preferences of coastal homeowners and the environmental goals of the agency.

Kate Venturini, of the URI Outreach Center, and one of the primary authors of the Native Plant Design Manual for Greenwich Bay, will present at the Ecological Landscaping Conference in Springfield, MA on February 25, 2010. Kate will discuss the development of the Native Plant Design Manual for Greenwich Bay as it relates to regulatory adaptation, the complexities of regulating vegetated areas, the value of selected LID practices for stormwater management on small, highly disturbed residential lots, and the paradigm shift towards native landscaping.