Background
The proposed study will examine any existing data from the monitoring wells, weather station, and flow through the storm sewer system (supplied by Buffalo Sewer Authority) to determine the dynamics of the system during storm events. Further analysis using all available information is needed to fully understand the relationship of events to the implementation of Green Infrastructure stormwater-control measure effectiveness. Questions to be addressed include: How do pipe flows and groundwater levels respond to storms? Can the data be used to quantify water-budget components at the site? To what extent can the effect of the Green Infrastructure in reducing stormwater volumes and peaks be quantified? Based on the current site conditions, are there additional pre-installation data that would help quantify the effectiveness of the proposed stormwater control measures at the site?
Problem
Combined sewer overflows impacting the Niagara River Area of Concern (AOC) have focused interest on stormwater reductions within the City of Buffalo and the Niagara River Greenway Project (NRGP). Replacing aging infrastructure provides the potential to install stormwater control measures to reduce peak flows. For the Niagara Street location in the City of Buffalo (fig. 1) urban green infrastructure has been proposed to reduce the volume of stormwater runoff thereby limiting the risk of combined sewer overflows. Implementation is scheduled to begin in the fall of 2016. Stormwater control measures will be implemented over a period of 2 years and include porous asphalt, stormwater planters, rain gardens, and the decrease of impervious pavements through the Niagara Street corridor; all designed to reduce stormflow to the local storm sewers. The City of Buffalo Sewer Authority along with the Buffalo Mayor’s Office of Strategic Planning, Department of Public Works, the University of Buffalo, and the US Environmental Protection Agency (EPA) have an interest in monitoring storm and combined-sewer flows along the Niagara Street corridor before and after installation of these stormwater control measures.
Monitoring at the NRGP location is needed to fully characterize the performance of the stormwater control measures over a range of hydraulic conditions. These stormwater control measures performance information could be used to design future phases of the proposed stormwater green infrastructures envisioned for the NRGP. The data collected through monitoring the effectiveness of these green infrastructure additions will be used to help design future stormwater control measures in urban projects around the Great Lakes and in other parts of New York State, such as Rochester and Syracuse.
Objectives
The primary objective of the proposed study is to quantify changes in storm-sewer flows through installation of stormwater control measures. More broadly, the study will build upon the characterization of green infrastructure and its relation to water-budget dynamics in an urban setting. The following specific objectives contribute to the primary objective.
● Improve the understanding of rainfall, runoff and infiltration interrelations in an urban area.
● Correlate meteorological variables such as precipitation, potential and actual evapotranspiration and intensity to stormwater discharge both pre- and post- construction of Green Infrastructures.
● Develop a calibrated model of the study area to simulate observed processes, quantify elements of the water budget, estimate effectiveness of stormwater control measures, and identify gaps in our understanding of processes affected by Green Infrastructure implemented at the site and extrapolated to the larger sewer shed.
● Increase spatial resolution of hydrologic data collected in the study area by adding more water-level monitoring and sewer-flow-monitoring sites.
Approach
Assessment of the effects of stormwater control measures implemented along the Niagara Street corridor will consist of 3 phases: monitoring, analysis, and modeling. The monitoring component includes measurement of potential evapotranspiration, precipitation, groundwater level, and storm sewer-discharge estimates. Monitoring of soil moisture content within the green infrastructure systems will be used to help explain absorption and infiltration rates in glaciolacustrine sediments. Initial USGS monitoring efforts will be funded by EPA through the Great Lakes Restoration Initiative (GLRI) program, and these efforts are expected to continue through 2017. Current funding, however, does not include multiple year monitoring, analysis and synthesis of the data, or modeling to estimate water-budget components or the dynamics at the site in response to storm events.
Project Location by County
Erie County, NY, Niagara County, NY
