[미국] MN, 나무를 이용한 폭우 관리 프로그램 개발


미네소타 주는 최근 폭우 관리를 위해 파이프보다 나무를 사용하여 지역 투자를 촉진하는 유형을 최초로 개발했다고 밝혔다. 이 방법은 잠재적으로 수천 달러를 절감한다.

Minnesota Pollution Control Agency는 새로운 폭우 매뉴얼의 한 부분으로 믿을만한 시스템을 만들고 어떻게 나무를 번성하게 하고 계획자와 개발자, 조경가, 건축업자에게 최대의 생물학적 이익을 제공하는지에 대한 권장안을 제공한다.

연방 수질오염방지법은 구체적인 지방자치제와 건축, 산업 활동으로부터 폭우 방출 요건을 도입했다. 미네소타는 지역사회와 파이브 설치의 높은 비용을 경감하기 위한 요건을 돕기 위해 다른 녹색사회기반시설이 나무를 사용하도록 돕는다고 설명했다.

The state of Minnesota has recently developed a first-of-its kind program that encourages communities to invest in the use of more trees rather than pipes to better manage stormwater -- potentially helping save thousands of dollars across the board.

The Minnesota Pollution Control Agency created the credit system as part of a new chapter on trees in their stormwater manual, which also provides recommendations on how to ensure that trees thrive and provide the maximum ecological benefits for planners, developers, landscape architects, and builders.

The federal Clean Water Act (CWA) imposes requirements on stormwater discharges from specific municipal, construction and industrial activities. Minnesota is helping communities use trees and other green infrastructure to help address these requirements while mitigating the high cost of installing only pipes. 

The new credit system is part of Minnesota's Minimal Impact Design Standards (MIDS), which focuses on treating rain where it falls to minimize negative impacts from stormwater runoff and to preserve natural resources. The credit is based on a formula that establishes criteria and methods to measure the benefits of evapotranspiration, which is the combination of water evaporating from the soil and transpiration from the plants growing in the soil.

An additional focus of the Minnesota stormwater manual is the importance of planting trees properly with adequate soil volumes, even in urban areas. The manual recommends soil requirements of two cubic feet of soil for a square foot of canopy area -- the minimum for a healthy tree.

Tree size is crucial for maximizing stormwater benefits. For trees that are planted and maintained correctly and provided with adequate soil volume, the state is therefore giving credits based on the projected mature canopy size. If a tree is planted with less soil than it needs, the credit is reduced.
As states look to alternative solutions to manage stormwater effectively, Minnesota and its new credit system is an example of what can be done through simple formulas and technology that help incentivize sustainable, tree-filled communities.

 

[출처 = Water World / 2014년 6월 19일]