This paper is intended to help the stormwater engineering community more easily account for trees in runoff and pollutant load calculations so that they can more readily incorporate them into their stormwater management strategies.
This worksheet was designed to help communities review and revise their development regulations, so that future projects conserve and protect valuable trees and woodlands and encourage new plantings. It provides a set of questions to help local officials determine whether local codes require, allow, or prohibit “forest-friendly” development practices. These practices were developed with input from subject matter experts including foresters, planners, transportation engineers, homebuilders, and fire administration representatives, to ensure that they maximize tree cover protection without compromising other goals, such as public safety, visibility, access, and economic value.
One of the major challenges to adoption of GI practices is uncertainty surrounding how they will be maintained. Operations and maintenance has been repeatedly raised as a technical barrier to adoption of green infrastructure and remains a concern for many local governments in the Chesapeake Bay region and across the country less familiar with these approaches. Similar to any type of infrastructure, without appropriate and consistent maintenance, green infrastructure will fail. For example, rain gardens can lose functionality and fail just like a neglected detention pond or a roadway. This report examines some of the major barriers to effective operations and maintenance of green infrastructure practices in the Chesapeake Bay region and identifies strategies and best practices that local governments, practitioners, and other groups are using to develop and improve maintenance practices.
Like all stormwater infrastructure, green infrastructure requires regular inspections and maintenance to assure proper function. Maintenance of green infrastructure generally requires more labor and less heavy equipment than maintenance of gray infrastructure. EPA lists resources which address what to look for when you inspect green infrastructure and how frequently to conduct maintenance activities.
Oregon State University maintains a website with guidance on installation of tree planters, rain gardens and bioswales. Useful for contractors, commercial property owners, and homeowners.
Detailed explanations and checklists for maintenance of different green stormwater practices.
The International Society of Aboriculture provides extensive training, continuing education and certification programs for green industry employees. For the sake of trees, always consider hiring ISA certified workers.
Coastal Resilience is a program led by The Nature Conservancy to examine nature’s role in reducing coastal flood risk. The program consists of an approach, a web mapping tool, and a network of practitioners around the world supporting hazard mitigation and climate adaptation planning.
The Hampton Roads Planning District Commission completed a study in 2012 that estimates a range of 1.5 feet to 5.5 feet of sea level rise over the next 90 years. Because of relatively flat topography, a large portion of the remaining tree cover along the city’s waterways is in jeopardy. Rising sea levels will lead to the inundation of wetlands, drowning wetland vegetation. In order to prevent permanent loss of wetlands, upland areas must remain open for wetlands to migrate and change. The beneficial tree cover provided by forested swamps will be lost if trees are unable to migrate inland. As the trees die, the area will become tidal grass-dominated wetlands.
NOAA has compiled an interactive site that allows communities to assess the future impacts of sea level rise. Use this web mapping tool to visualize community-level impacts from coastal flooding or sea level rise (up to 6 feet above average high tides). Photo simulations of how future flooding might impact local landmarks are also provided, as well as data related to water depth, connectivity, flood frequency, socio-economic vulnerability, wetland loss and migration, and mapping confidence.