2015 Conference

Full Presentation Panel

We are facing increasing complex environmental problems that will require interdisciplinary solutions. One such solution is green infracture (GI) or low-impact development (LID), which are decentralized and sustainable design practices used in urban environments to reduce stormwater runoff and improve energy efficiency. GI/LID approaches include maintaining natural landscapes, and implementing green roofs, porous pavement, rain barrels. GI/LID solutions have been shown to mitigate the effects of climate change, cool buildings and paved surfaces, improve water quality, and reduce flooding; the EPA claims that “applied on a broad scale, LID can maintain or restore a watershed's hydrologic and ecological functions.” But there is some question of the effectiveness of GI/LID in addressing environmental problems, especially give economic and other barriers to its effective implementation. In this full presentation panel, we address these issues from multiple disciplines and perspectives.

The Role of Green Infrastructure to Mitigate Vulnerability of Water Conveyance Infrastructure Due to a Higher Frequency of More Extreme Precipitation Events

Michael Simpson

Results will be presented from NOAA funded research in the Hiawatha Lake watershed in Minneapolis, MN. This research examined the hydrologic impact of climate change and land use scenarios on existing water conveyance infrastructure. One key scenario was incorporating green infrastructure through storm water fee rebates for this built-out urban landscape.

This build-out scenario was combined with estimated, mid-21st century storm magnitudes based upon downscaled global greenhouse gas emission scenarios. Once vulnerable zones within the City were identified, a marginal cost analysis was completed incorporating the efficacy of green infrastructure in the context of off-setting alternative methods of storm water mitigation.

The technical outputs of these studies informed concurrent community resilience building processes that increased stakeholder capacity at the local level in adapting to change.

The Economics of Green Infrastructure as a Demand Management Strategy
Yehuda Klein

UHI is a significant concern in high-density urban hubs like New York City. The thermal storage potential of urban centers keep urban temperatures high through out the day and into the evening. The New York Independent System operator map of New York electric demand identifies the southeastern New York (SENY) region as a “load pocket”, an area of high electric demand the requires electricity delivery from outside the region to supplement the in region electricity supply during warm summer months.

Based on the work of Gaffin et al on green roofs on a Queens office building, summertime energy savings can be achieved during the summertime air conditioning season using green roofs. Previous economic analysis of green roof associated cooling load reduction neglects an important aspect of the New York State energy market. Standard cost of energy assessments of the cooling effects of green roofs neglect the potential for “peak demand reduction”. The dollar value of peak demand reduction in New York State is many times greater than the standard electric rates. In this paper we examine the economic value of green infrastructure for electric demand management in New York City.

Residents Preferences for Adoption of Low Impact Development Practices
Zahra Golshani

Low impact development (LID) practices are innovative decentralized stormwater management strategies to manage urban stormwater run off. LID practices provide multiple ancillary benefits while managing the stormwater run off. Therefore, widespread investment in LID practices would not only manage the stormwater run off but also would yield multiple benefits for societies. Residents and households as potential investor and adopters of LID practices can play a major role in successful implementation of LID practices. Therefore residents’ response and motivations to invest in LID is of important value to stormwater managers and program developers. By learning about incentives and barriers to adopt LID, stormwater managers would know what issues to address when designing stormwater management programs.

LID practices provide a combination of private and public benefits and costs that would affect residents’ decision making when selecting an LID practice. This study is designed to examine the role of selected private and public LID attributes and characteristics on residents decision making. The study employs a multi-attribute discrete choice modeling to examine the role of selected attributes of LID techniques on residents’ choices and willingness to pay for those practices. The results of this study is useful in policy context by identifying which attributes of LID practices are significant determinants of the values people place on these practices (at residential level), the implied ranking of these attributes, preferences and willingness to pay for attributes and the trade off made between selected attributes when evaluating the adoption of different LID practices.

Assessment of the Effectiveness of Green Infrastructure at Improving Water Quality and Reducing Flooding at the Watershed-Scale
Kate Meierdiercks

The processes that control runoff quality and quantity in urban watersheds are complex and not well understood. While impervious surface coverage has traditionally been used to examine altered hydrologic response in urban watersheds, several studies suggest that other elements of the urban landscape, particularly those associated with urban infrastructure and the drainage system, play an equally important role. Research from the Kromma Kill, an urban watershed located in Albany County, NY, suggests that while percent impervious coverage can be used to predict general water quality, other elements of the urban landscape, particularly those associated with subwatershed slope and drainage network structures, have a greater impact on the magnitude of flood response and specific water quality parameters than percent imperviousness. Thus watershed plans that rely only on reducing the percentage of effective imperviousness of the watershed may not serve as the most effective solution for every management objective. Here, we assess the effectiveness in improving water quality and reducing flooding of green infrastructure (GI) and other stormwater management strategies that aim to reduce the percentage of effective imperviousness versus those that target the drainage network system. These issues are examined in the subwatersheds of the Kromma Kill using monitoring data and a rainfall-runoff model.