Green Infrastructure Assessment
To meet the performance standards outlined in the Consent Decree agreement with the United States Environmental Protection Agency (USEPA) the Metropolitan Sewer Districts (MSD) has begun implementing a green stormwater mitigation program to address overflow events combined sewer watersheds located within the urban core of Louisville, Kentucky. The initial phase of the program began with the installation of two interlocking concrete pavers (ICP) (Identified as 19D and 19E) serviced by infiltration galleries just south of the intersection of Adams Street and East Washington Street, see highlighted area in figure 1. The ICP installations serve combined sewer overflow watershed 130 (CSO 130), which serves the Butchertown neighborhood.
As part of this program, MSD is working with Center for Infrastructure Research (CIR) at the University of Louisville and the USEPA Office of Research and Development to develop right sizing standards and best management practices through monitoring and analyzing the green practices performance through onsite testing and embedded monitoring equipment.Below is information discussing the results of the current maintenance protocols being implemented.
The objective of this phase of this project examines maintenance practices and frequencies to develop a best management practices document. This report evaluates current maintenance protocols through surface infiltration testing and analysis of the clogging material.
The first phase of construction consisted of two ICP installations, 19G and 19H, installed in CSO 130. Table 1 provides an overview of the characteristics for each control while figure 2 provides a cross-section profile of the each control.
The Pave Drain System was selected for this installation due to their ease of installation, durability and designs which provides a more natural (vertical) infiltration path for overflowing surface stormwater. Additionally, the paver sheets are interconnected via a series of wires, allowing the pavers sheets be easily removed to gain access to the infiltration gallery material if needed.
The pavers where installed in 8’x8’ sheets by an excavator and required manual manipulation during installation. Each block is about 12 inches on each side and 5.5 inches tall, with the arc going 2.5 inches deep inside the paver block