Low Impact Development: A Myth or Proven Practice?

By: Jill Pfeiffer-Ward, P.E., LEED AP, CPESC – Project Manager

My job gives me the opportunity to collaborate with co-workers who conscientiously bring low impact development (LID) practices into our projects, and at Environmental Design Group, we do what we can to incorporate this practice because we know it’s making great impacts not only on the environment but on long term economic development.

In engineering language, LID is a land planning, engineering design and ecosystem based approach to stormwater management, that is multi-functional and derives positive environmental and social benefits.

There are some myths about LID that may help clarify the benefit of this engineering practice in your next design project:

IMG_9604An office building bioretention with flow attenuation

Myth #1 – LID isn’t valuable:

LID techniques in stormwater such as sediments, bacteria, and hydrocarbons are filtered out before the stormwater reaches the natural environment. It reduces the volume of stormwater runoff while slowing down the speed at which the stormwater leaves the property. It enhances community beauty because LID solutions are integrated with adaptive landscaping and provides a space that is aesthetically pleasing and wildlife friendly. Do you still think LID isn’t valuable?

Myth #2 – LID is too expensive:

There was a time when the material costs for LID (including permeable pavements, bio-retention, green roofs, rainwater harvesting, etc.) were high and regulators were not receptive; however, with changing and advancing times, this is no longer the case. With our projects, it has shown to reduce construction costs by reducing pavement surfaces and road widths. When integrating stormwater handling into landscape areas, this reduces the cost of separating stormwater facilities, and maintaining natural landscape areas also reduces stormwater volume, which lowers flooding hazards, and minimizes maintenance costs. If done properly, LID practices will provide a positive return on investment.

IMG_0624An office building green roof

Myth #3 – LID isn’t aesthetically pleasing:

This is a trivial myth because the LID techniques we implement provide very aesthetically pleasing spaces that everyone can benefit from. We take the space design into consideration to ensure the appearance fits well with the project footprint. By adding park-like elements to streets and parking areas, it provides habitat for animals and beneficial insects, it increases a sense of quality to the area, while providing recreation opportunities in the form of pedestrian access routes.

Myth #4 – LID is difficult and costly to maintain:

It is true that maintenance costs of LID may be higher for the first few years as vegetation becomes established, but consider it a long-term investment. Once the vegetation is established, the operations and maintenance costs will be lower than the cost of maintaining traditional stormwater facilities because LID maintenance will be equivalent to traditional landscape maintenance costs, without having to maintain a separate stormwater facility.

Rain Garden
Rain garden at an office building that mitigates flood issues

Low Impact Development is an approach to stormwater management that is providing a positive effect on communities by enhancing the ecosystem with a “divide and conquer” theory to treat stormwater.  This concept is instilled in my efforts to provide our projects a sense of place in the communities we serve while addressing negative stormwater impacts. In my eyes, it’s a win win!

The Ohio & Erie Canal Towpath Trail: Growing One Stage at a Time

Written by: Jeff Kerr, Principal, PLA, AICP, ASLA

The Ohio & Erie Canal Towpath Trail has more than 2.5 million visitors running through the heart of the Ohio & Erie Canalway. Whether biking, hiking, running, horseback riding, traveling alongside it by scenic rail, the Towpath Trail means something different for everyone.

Osborne_FullSite_WhiteThe Stage 3 Trail will pass under Clark Avenue to a new trail head and parking lot

About 20 years ago, the Cuyahoga Valley initiative defined strategies for protection and recovery of the valley’s natural character, and methods to use the rich heritage and unique historic and industrial features for economic growth and tourism.

The plan also provided new and sustainable ways for businesses to form and grow as a result of embracing these attributes, and the means for adjoining neighborhoods and visitors to the region. This initiative has evolved into the development of the Towpath Trail in Cuyahoga County.

NEW Cuyahoga Cty Towpath Stage 3 Profile
The stage 3 trail starts to rise to a new bridge that will cross West 7th Street to an area called, The Bluff

Environmental Design Group is honored to work on the towpath trail from early origin through today’s design. This effort has guided the ever expanding network of trails, and on Saturday, April 22, Canalway Partners will host a groundbreaking ceremony to celebrate the next phase of trail design.

This event signifies the stage 3 phase of trail expansion extending 1.9 miles from the northern entrance of Steelyard Commons to Literary Avenue, and we’re proud to be part of the design and construction.

Sit back and enjoy the ride as we take you on a video tour of the stage 3 trail development!

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When Size Matters: A Green and Complete Street Retrofit Case Study

Written By: Katherine Holmok, Director Parks, Trails, Green Infrastructure

For anyone who has constructed green infrastructure in a roadway right of way, identifying opportunities within the spaghetti system of utilities can keep you awake at night. Gas lines, fiber optics, electrical duct banks, above ground utility poles, street signage, street trees and guard rails, can all shrink the potential BMP implementation footprint to negative numbers. That’s why it’s important to step back from the prescribed BMP manuals, consider why these design standards were created and find inventive new designs and technologies to provide the same or better benefits. The Marshallville Park Street Green and Complete Street project is a juxtaposition of BMP design standards with multiple new design methodologies and technologies, contrasting each system in a singular area.

before2.JPGBefore Construction – Typical Ohio rural residential street with no sidewalks and flat grading

The Village of Marshallville, with a population just under 800, is located in the eastern part of Wayne County, Ohio. Localized flooding and drainage have always been a concern for the Village. Geographically located at the headwaters of the Tuscarawas River, there is very little topographic relief in the Village and soils are heavy clay with low permeability.

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Pervious Concrete sidewalk captures and stores stormwater from the newly repaved road

The Village owns and operates its own utilities including water, sanitary sewer and electric services. Over the past ten-years, the Village of Marshallville has been proactive with efforts to upgrade its infrastructure including a new wastewater treatment plant, waterline upgrades, wetland creation and various street improvements.

The Village was in need of replacing a water line along Park Street, which was the last segment in the Village wide water infrastructure improvements. Additionally, this segment of Park Street is one of the last sections of walking paths to connect the Village Park to the future Rails-To-Trail (Heartland Trail). The Village of Marshallville plans to remove and repair a portion of the road to install this water utility providing the opportunity to install cost effective stormwater mitigation through the creation of a demonstration suburban green and complete street.

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Four different technology bioretention areas capture and treat stormwater runoff while providing an aesthetic amenity

The completed design included a utility friendly pervious pavement all-purpose path that captures and treats stormwater on one side of the street. The typical rectilinear pervious pavement installation was modified to incorporate an underground infiltration trench, which weaves in and out of underground utilities. A portion of this trench also uses expanded shale technology (Haydite), which can provide additional water quality benefits in a cost effective manner. This is designed to capture and enhance infiltration for a 1yr/24hr storm while still enabling drive access, pedestrian traffic and room for underground utilities.

The opposite side of the street includes four different bioretention designs and technologies. Two of the four technologies include high flow rate soils, which allow stormwater to flow faster through the media, elongating the stormwater’s contact with existing below ground soils, thereby expanding the overall infiltration potential. The remaining two technologies are typical bioretention designs prescribed in the Ohio Department of Natural Resources Rainwater and Land Development Manual (2012 and 2014). No other application in northeast Ohio includes these four technologies juxtaposed in a way that allows scientific study of the operation and maintenance of these technologies.

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One of the new technologies used is a high flow rate bioretention system called FocalPoint. This T.A.R.P. tested system provides equal water quality treatment with a smaller footprint than a traditional bioretention.

The Village of Marshallville is continuing with its proactive efforts to improve the health, well-being and environmental aspects of its citizens and become a regional example of pragmatic sustainability. Five years ago the Village installed a wetland next to their waste water treatment plant and last year installed a solar field. This project provides a new regional design model for suburban stormwater control through a simplified Green and Complete Street Design.

The project was wholly funded by grants from the Ohio Environmental Protection Agency, Muskingum Watershed Conservancy District and Ohio Public Works. The Village will provide post construction operations and maintenance of the project. The project also includes permanent educational signs at each of the BMP sites. Click here for the Marshallville Green & Complete Street fact sheet.

Case Study: The Importance of Flood Study Field Observations at Wolf Creek

By: Jim Demboski, P.E., Project Manager and Andy Long, Design Engineer, E.I.T.

flooding-river

“We have flooding problems.” It’s a phrase that makes everybody cringe and run for higher ground and rightfully so. Historically, humans have done anything from dredging, installing berms and levees, to installing large storage basins to prevent flooding, but how do we get to these solutions? We perform flood studies of course! The level of effort it takes to perform a flood study can vary significantly not only based on size, but complexity of the study area.

A preliminary flood study was performed on a small portion of the lower Pigeon and Wolf Creek Watersheds. Although the study area was only a small portion of the watershed it was particularly complex because it contained a reservoir, which main purpose is to supply drinking water to local communities.  It’s also a confluence that has back watering effects, and last but not least, a developed flood plain with restricted and complex flow paths and storage areas. After initially gathering more information about the study area and developing the hydraulic model, we knew that field observations were going to be important.

To give a little background, Wolf Creek is a 13.1-mile-long tributary of the Tuscarawas River, draining 77.6 square miles of land from numerous municipalities including Fairlawn, Medina, Barberton, Norton and Akron. In the 1930s, Wolf Creek and its tributaries, such as Pigeon Creek, Schocalog Run, Viers, Copley Frederick, Weinpert, Rousche, Black Pond, Bessemer, Infirmary, Hands Lateral and Frank, were deemed county ditches. Historically, these ditches have been deepened, widened, straightened, and maintained in an effort to offset the increased discharge volumes and rates that upstream urbanization has contributed to the watershed. The watershed frequently floods its surrounding communities from not only over topping banks, but also from backed up storm sewer systems.

pigeon-and-wolf-creek-watershedsPigeon and Wolf Creek Watersheds

To me, one of the great things about performing a flood study is that it provides a perfect balance between work and “play.” It’s a great opportunity to get into the field and enjoy nature. Not only was going in the field an enjoyable break from the number crunching, it was a crucial part in making changes to the hydraulic modeling for this project.

Field observations for this study were particularly important to generate numeric values that affect how water is conveyed through the study area.

depth-measurements
Performing depth measurements to compare with surveyed streambed

For this particular flood study, we collected stream and reservoir stage information, which were at the upper limits along with stream stage information at an intermediate location within the modeled stretch.

The team would often go out to record high water marks, take pictures and make observations, which couldn’t be done sitting behind a computer desk, even with stream gauges installed. We found that another great tool for collecting stream stage information at various structures was to utilize a well level sensor that our environmental staff uses to measure water well depths, which was particularly useful in the dark.

well-level-sensorUsing a well level sensor to measure stream stage at Norton Avenue Bridge

Following a cold, wet night, the team would go into the field to observe the presence of what we thought to be an existing storage area near the confluence of Pigeon and Wolf Creek. Having a basic understanding of how water enters and exits this area was important because it impacted the hydraulic model.

existing-storage-areaObserving the existing storage area

There were some great takeaways from this study, and we learned that no matter what the objective of the study, field observations are pertinent to help understand and better interpret the modeling results, which helped influence some of our conclusions and recommendations.

How important do you consider field observations for a flood study?  At Environmental Design Group, we believe it’s a crucial step in creating the greatest environmental impact.