White Island, an 80-acre former municipal landfill located in Brooklyn, New York, is one of the first grassland mitigation projects required by New York State. The former landfill was constructed on historic marsh land and exhibited severe shoreline erosion due to wave action and tidal flux. Additionally, over 80 percent of the island was dominated by invasive species. The project involved bioengineered shoreline stabilization, invasive species control, and grassland habitat creation. The project served as mitigation for the loss of 56 acres of maritime grassland habitat due to construction of a nearby Housing Development and Retail Center. The NYSDEC determined the loss of grassland habitat was a significant adverse impact on several bird species and the creation of new maritime grassland habitat on White Island was required as compensatory mitigation. The main objectives of the restoration design were to:
• Improve shoreline stability;
• Control invasive species;
• Create habitat for rare or special-status species; and
• Increase biodiversity.
While traditional armoring could have been used, vegetative bioengineering stabilization practices were selected to provide a connective vegetated zone along the shore for wildlife use. The vegetation also provided a long-term and low maintenance solution for the island site. A combination of a cellular confinement system and articulated concrete blocks were used to provide additional stability while the plants were establishing. The design incorporated several vegetative zones to provide suitable diverse habitat for ground nesting avian species, while supporting habitat for other wildlife. The vegetative zones were designed to provide contiguous acres of suitable grasslands habitat, maximize edge diversity, provide shelter and control erosion. Over 150,000 cubic yards of sand was installed across the island surface to create a planting substrate free of invasive species for the colonization by a variety warm-season grasses.
Immediately following construction, the east coast was struck by Superstorm Sandy. The lessons learned from this extreme testing of vegetated shoreline stabilization techniques will be discussed.
- 1. Discuss the pros and cons of alternative shoreline/bank stabilization compared to traditional armoring techniques.
- Recognize the conditions where bioengineered stabilization measures are preferred.
- Discuss alternative shoreline/bank stabilization measures and why they are effective or ineffective.
Course Level: All
Last Updated: January 16, 2019
|Activity Number||Credit Amount||Accreditation Period|
|IECA PDH Webinar||1 PDH||from January 16, 2019|