Beautifying Pollution Control

June 6, 2007

About the author: Joshua J. O’Neil, PE, is project engineer and Stephen M. Way, PE, is principal and managing director for DGL Consulting Engineers, LLC. They can be reached at 419/535-1015, or by e-mail at [email protected] or [email protected].

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The J. Preston Levis Commons

Development is a distinctly unique, top quality, master-planned community built on 400 acres in northern Wood County, Ohio. It is strategically located just minutes from the Dixie Highway (S.R.-25) interchange with U.S.-23/I-475 in the Toledo suburb of Perrysburg. Entrance drives to the development exist on three of its four sides; however, the centrally located signature entrance is the Michael Owens Way Boulevard, which intersects with Roachton Road on the south side of the 400-acre plat.

Michael Owens Way is the main access to Owens-Illinois, Inc.’s (O-I) world headquarters and the backbone for the Levis Commons Development, off which other through streets will intersect, while also intersecting with Roachton Road a short distance from the recently constructed Perrysburg High School and surrounding residential developments.

Background

Nestled within northwest Ohio is a region formerly known as the “Great Black Swamp.” The swamp was a glacial lake bottom and consisted of very flat topography with impermeable silt and clay soils with occasional sand ridges. Wet forests of hardwood, shallow lakes and prairies covered the swampland.

Between the water, vegetation, mosquitoes and malaria, and the heavy and sticky mud, European settlers found the swamp an obstacle to development. Settlement and farming eventually came to northwest Ohio and it became one of Ohio’s best agricultural regions; however, it required draining of the swamp through an extensive system of ditches. It has been estimated that a total of three miles of man-made ditches to every mile of natural stream exist within the region.

The drainage ditches make productive farming possible, but many of them do not provide fish or wildlife habitat. Many of these ditches lack buffer areas and are farmed right up to the ditch bank, thus providing a direct route for nutrients and sediment runoff to Lake Erie. Despite draining and channelizing streams, the swamp still exists.

Lake Erie water quality

“Eutrophic” is a term that describes a lake enriched with nutrients (phosphates and nitrates) and organic matter. That enrichment results in an increased rate of biological productivity. Studies in the 1970s and ‘80s identified phosphate as a critical nutrient for eutrophication. For Lake Erie, “over-nourishment” meant accelerated nuisance growths (blooms) of cyanobacteria. These blooms are still popular and are called “toxic algae.”

The immediate effect on Lake Erie was to make it an unpopular recreational location due to cyanobacteria’s strong odor. The effect did not end there, however. During the winter season, these blooms would die and sink to the lake floor where they covered fish spawning and feeding locations. Ultimately, the decaying blooms would deplete dissolved oxygen from the water that fish and aquatic life needed to survive; the result was an area within the lake known as a “dead zone.”

Water quality continues to be a growing concern throughout northwest Ohio and the Great Lakes region as a whole. Legislative action and proactive changes to the management of surface runoff have resulted in significant improvements in water quality throughout the Great Lakes and the elimination of a majority of the dead zones that were prevalent; however, the improvements realized in Lake Erie have declined since the 1990s.

This condition was noted at the same time that Zebra Mussels spread throughout the lake and impacted the environmental balance. Scientists do not completely understand the ecological impact these creatures had on the system; however, they do believe a change in the nutrient routing through the ecosystem did occur.

In 2002 and 2003, the dead zone within Lake Erie’s central and western basins and the toxic blooms returned. It is unclear what happened to cause the reoccurrence, although the intrusion of increased levels of phosphorus into the lake is suspected.

Regional objectives

In its “Areawide Water Quality Management Plan,” the Toledo Metropolitan Area Council of Governments stated:

Phosphorus is considered the critical nutrient where Lake Erie is concerned, but “algae blooms” also require nitrates. Concern over nitrate usually centers on its drinking water impacts, but does it also control algae growth? The question is important to public policy. Nitrates are soluble in water, so controlling nitrates means controlling water. Phosphorus attaches to sediment, so controlling phosphorus means controlling sediment. What should be the priorities of environmental agencies?

Our conclusion is that our primary focus needs to be reduction of sediment and phosphorus, but in conjunction with stream habitat restoration … For bays and Lake Erie, research and policy emphasizes phosphorus and sediment reduction to control nuisance “algae blooms” and protect aquatic habitat.

Sediment is a pollutant in its own right. Ecologically, it is important because phosphorus attaches to it and is carried with sediment. Generally speaking, actions that reduce the amount of sediment going into Lake Erie will reduce the amount of phosphorus. When sediment settles out, it covers the bottom of streams, bays and Lake Erie. Doing so, it covers fish feeding and spawning areas.

There continues to be quite a bit of specification development relative to sediment and erosion control within construction sites and the implementation of post-construction best management practices (BMPs) within the industry; however, all involved seem to be in agreement that the long-term control of sediment will have ecological benefits to the Lake Erie water quality.

In Ohio, non-point source programs are managed by the Ohio Environmental Protection Agency (EPA) and Department of Natural Resources; these agencies have typically taken the position that reducing the impacts from non-point sources is a matter of prevention through BMPs. A BMP should:

  • Be effective in reducing water pollution from non-point sources;
  • Be effective in helping waterways meet Clean Water Act “fishable and swimmable” goals; and
  • Be practicable.

Project development

The project use of storm water pollution prevention techniques during construction, as well as post-construction BMPs, were being monitored by the Ohio EPA. Michael Owens Way was designed as an asymmetric boulevard with multi-use pathways winding their way through more than 3,000 plants and trees to create a calming experience for the traveler within the corridor. The design results in a linear park setting that has characteristics similar to New York City’s Central Park.

Further accentuating the calming experience provided by the corridor is the innovative bioswale design used to clean storm water prior to its leaving the project site. The use of this bioswale technique eliminated the need for other more conventional design methods (detention ponds), which would have required more land area and detracted from the corridor’s beauty while adhering to all Ohio EPA current regulations.

Design criteria & approach

The design team’s first objective was to develop a method in which the urban runoff from Michael Owens Way could be “cleaned” prior to entering Perrysburg’s storm sewer system without detracting from the architectural theme of the corridor. Perrysburg’s storm sewer system in this area of the city outlets into Schaller Ditch and eventually the Maumee River. The solution was a bioswale hidden within the boulevard’s center median.

The bioswale was designed to clean runoff resulting from a two-year design frequency storm (first flush). The cross-section and grade were engineered to limit the depth of flow to less than 6 in. and the velocity to a rather slow 1 ft per second. By utilizing this criteria and introducing grasses and aquatic plants that could withstand the pollutants that would be entering the bioswale from the adjacent boulevard, the result was an aesthetically pleasing BMP that adhered to the regional goals of limiting the amount of sediment that is intro duced into the Maumee River and Lake Erie. Although the bioswale was designed as a BMP, it also serves as the primary drainage system for Michael Owens Way and meets all local roadway drainage design standards (e.g. 10-year design storm frequency).

The performance of the bioswale is dependent on the boulevard cross slopes set to drain toward the center curb lines where a series of Neenah Foundry R-3165 curb inlet frames, grates and curb boxes were positioned. The use of the curb boxes, in lieu of the more traditional catch basin, allowed a 12-in. outlet pipe to drain directly into the shallow bioswale. The use of this system provided additional benefits to the project overall, the most notable of which was the relative flatness of the site, and the required hydraulic gradient was not going to allow a normal ditch section to drain back into Perrysburg’s storm sewer system.

Landscape and streetscape

enhancements are abundant along the roadway and linear park. The trees and low-level plantings were specifically selected to provide four-season attraction in northwest Ohio’s climate. Decorative bollards, brick pedestrian ramps, stamped and colored crosswalks, lighting and other features also are present. Levis Commons adheres to strict architectural standards that require all plans to be reviewed and approved by an architectural review committee (ARC). DGL Consulting Engineers worked closely with the ARC to exceed the architectural standards required in the development.

The ribbon-cutting ceremony for the roadway was held on Aug. 18, 2006, in conjunction with the opening of the O-I world headquarters that is located at the head of Michael Owens Way. City of Perrysburg Mayor Nelson Evans and Larry Dillin, president of the Dillin Corp., cut the ribbon at the signature entrance. The pride that Perrysburg has over its Michael Owens Way boulevard and the Levis Commons Development was summarized by Mayor Evans: “I believe Michael Owens Way will set the new standard for roadway design and entranceway enhancements. Certainly it has raised the bar for Levis Commons, if that was even possible.”

The authors would like to acknowledge the Toledo Metropolitan Area Council of Governments, Toledo, Ohio, for its contribution of historical data and confirmation of regional environmental policy that was included within this article. For further information: www.tmacog.org.

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