A Piece of the Puzzle

Putting together stormwater treatment with permeable pavers

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Credit: Jeff Knopp, Behnke Landscape Architecture
Long-time football coach Vince Lombardi once said that the greatest accomplishment isn’t in never falling, but in rising again after you fall.

Cleveland, OH, a city once known for industrialized manufacturing and a major hub on the Cuyahoga River, experienced a fall of sorts in 1969 by way of river fire. The fire that would later change American environmental history began when sparks from a train ignited the debris-filled oil that lay several inches thick on the river surface. It wasn’t the first time the river caught fire; an estimated 13 fires had occurred since 1868. The causes: oil slicks, garbage, and being one of the most polluted rivers in the United States.

The 1969 fire, however, happened at a time when attitudes across the country were changing, and Time magazine brought nationwide attention to the Cuyahoga River. Congress became involved, the National Environmental Policy Act (NEPA) was passed in January 1970, and the Environmental Protection Agency was established later that year. One of the first policies the EPA set forth was the Clean Water Act of 1972.

Since 1969, the Northeast Ohio Regional Sewer District (NEORSD) has invested more than $3.5 billion to help clean up the Cuyahoga River and update sewer systems. It’s projected that number will rise by another $5 billion for the upkeep of the wastewater system.

The good news is that there has never been another river fire, and some 60 different species of fish are now found in the river. In 1998, the Cuyahoga River was listed as one of 14 American Heritage Rivers. And each year Cleveland finds new technology to help with waste management and provide better sanitation to the river and its tributaries.

The Metropolitan Water Reclamation District of Greater Chicago is seeking a visionary Executive Director. The District is an award-winning wastewater agency which has been a leader in protecting the Chicago area water environment for over a 120 years. For information and to apply, click here or contact [email protected]The District is an Equal Opportunity Employer.
Photos: Ken Bukowski, GPD Group
Preparing to join precast walls together

The Flats
As part of the vast re-emergence of Cleveland, riverfront properties that were once in a run-down and neglected district of the city have become a place for investors to help restore the area to prominence. Called The Flats East Bank, the picturesque waterfront development site features more than $750 million in new developments including a 23-story hotel and numerous restaurants.

When phase two of the development opened in 2015, it featured a 241-unit high-end apartment building with restaurants, music venues, and a gym. These apartments, approximately 720 to 986 square feet, have been primarily aimed at attracting millennials to the area. Included in the project is an extensive riverfront boardwalk area known as the Riverwalk. In keeping with the historical authenticity of the Flats district, the city specified that Main Avenue be paved with tumbled clay pavers to emulate old-time brick roads. Further, the developer paved other roadways with clay pavers similar in style to those of Main Avenue; these roads include West 11th, Front Avenue, and Old River Road. Permeable StormPave pavers from Pine Hall Brick were used.

The space between the StormPave pavers allows rainwater to flow through, collect in aggregate below, and then drain to the soil to filter naturally. Another option is to allow runoff to flow through the pavers and aggregate, then be directed to storage tanks or other sealed areas, as in the Flats project.

Jeff Knopp, a principal with Behnke Landscape Architecture in Cleveland, explains that because the development is a brownfield site, certain precautions were necessary. Brownfields are properties where redevelopment or reuse is problematic because of the previous presence of contamination of some kind. EPA has a brownfield program to help fund environmental assessment and cleanup of the sites through a grant program. Challenges associated with brownfields include environmental liability concerns and cleanup considerations.

Join us in Atlanta August 18–22, 2019  for StormCon, a five-day special event to learn from experts in various water-related arenas.  Share ideas with peers in your field and across industries—exploring new stormwater management practices and technologies.  Click here for details

Ken Bukowski, project manager with GPD Group, a civil engineering firm also in Cleveland, took these considerations into account in designing the site. One measure was the use of 48-inch-high curb walls—including secured rubber liners—that he designed to craft a “tank” of sorts. These curb walls keep surface runoff from moving to the groundwater level.

“We capped the below-grade subsoils, created walls around the perimeter of the pervious pavers, and lined it so the water gets in there, but does not intermingle with the groundwater before it gets to the river,” he explains.

The site was also designed with an 8-inch-deep detention storage zone, positioned below the 28-inch regional design frost depth. This was the critical and controlling factor for the depth of the entire system.

Installing the Pavers
A pedestrian plaza connects the Riverwalk to a mixed-use area where the community holds festivals, concerts, and street fairs. Knopp explains how the Pine Hall Brick pavers contributed to the plaza’s design.

“The project has two circular roundabouts. Pavers in these areas were installed in a circular pattern,” he says. “We also installed pavers in a circular pattern at a third intersection to complement the design at the roundabouts. In front of the new apartment building, we installed a large semicircular pattern of pavers, as this area is intended to be a congregational space for special events such as concerts. The remainder of the pattern was a herringbone pattern on roadways.”

“We went through everything in the way of options,” says Bukowski. “We were looking for both aesthetics and function.”

Changes in design and color of the pavers define a vehicular zone for daytime driving and deliveries made to area businesses. However, keeping with the theme of neighborhood community, pedestrians remain the priority users of the plaza.

Great Lakes Crushing was hired to install the major infrastructure for the development, including the water-quality system components, notes Bukowski. Local Royal Landscape Gardening was hired to install the StormPave pavers.

“The first phase of development involved construction of the primary roadways around the Aloft Hotel and Ernst and Young Office Tower. This phase was farthest away from the river; there are large plaza areas associated with these buildings,” explains Bukowski. “There are green roofs incorporated into these plaza areas along Main Avenue. Rainwater flows from the upper roofs, and green roof overflows flow down to an underground, extended detention treatment storage tank. There’s also a bioretention area, which treats a large portion of the one upper tower roof. From there, it then goes to a second extended detention treatment storage system before it is discharged into the newly installed dedicated stormwater-only sewer. This removes excess flows from going into the NEORSD’s combined sewer system. This helps NEORSD’s efforts of reducing or eliminating overflow events.”

After dealing with multiple complex utility infrastructures they had installed below the project, crews were finally ready to install a whole new drainage system to continue rerouting stormwater away from the combined sewer system. The selected roadways with permeable pavers as well as parking lot detention systems allow water to drain off roads and surrounding surfaces but do not allow it to reach the groundwater.

“West 11th Street has 12,450 square feet of permeable pavers,” notes Bukowski. “In that drainage area, [runoff from] the roadway and adjacent surface areas all the way up to the building faces is being captured and treated. Then there’s the Old River Road; that’s the circular part along the river. It actually has two parts—one is the roadway or vehicular pathway and the other is for the pedestrian sidewalks. The vehicular pathway is composed of 10,800 square feet of pervious pavers, and the sidewalk area has 5,750 square feet. So, project totals include 29,000 square feet of permeable pavers, which are managing approximately 1.66 acres of drainage area that’s being captured and treated.”

Because of weather conditions, the curb sections had to be cast elsewhere and brought to the site for installation. But the biggest challenge was that everything had to be constructed on a tight deadline. All the elements—buildings, parking lots, streets and sidewalks, mainline and secondary utilities, and the 900-foot long Riverwalk—had to be completed in time for a grand opening. The work also included an Ohio Department of Transportation Main Avenue bridge rehabilitation effort that was underway at the same time.

“This certainly was an awesome and involved project,” says Bukowski.

According to Jane Goodman, executive director of Cuyahoga River Restoration, the group charged with responsibility for overseeing the river’s cleanup, what’s needed is a way for more water to get into the soil, which means more trees.

“In order to really recover the water quality, we will need to replace impervious surfaces with permeable surfaces, which is why we love permeable paving,” says Goodman. “And the fact that these are put in adjacent to impervious surfaces is a really important factor in making permeable paving so attractive, so useful, and so effective.”

Spring Street Beer and Wine Garden
Before the Spring Street Beer and Wine Garden in Houston, TX, opened in 2016, owner Hamilton Rucker had already decided the former gas station site would have as little impervious cover as possible, explains Bryan Brown, owner of Texas Eco Pavers.

In an area that receives approximately 50 inches of rainfall annually, this was a prudent decision to protect his investment.

Located in the southeast part of Texas near Galveston Bay, Harris County has a population of more than 4 million, making it the third-most-populated county in the United States. With a little over 599 square miles, it’s considered to be the largest urban metropolis in the state.

Historical Storms
Residents of Texas, and those who live in Houston in particular, are no strangers to floods and tropical storms. After historical flooding in 1929 and again in 1935, the state legislature created the Harris County Flood Control District and charged it with implementing flood-damage reduction strategies and maintaining the primary drainage infrastructure.

In 1982, the district brought 13 gauge stations online to monitor stream and bayou levels. From 1983 to 2018, it gradually increased the station number to 163. These stations are part of the district’s Flood Warning System, which measures rainfall levels in real time and monitors increased water levels in streams and bayous. The Harris County Office of Homeland Security and Emergency Management uses the information to keep residents informed of potential danger to families or property.

Harris County experiences turbulent tropical storms coming from the Gulf of Mexico. Tropical Storm Allison, which delivered 40 inches of rain to Houston in 2001 and caused billions of dollars in damages, was considered the area’s worst flood at that time. Then in September 2005, Hurricane Rita threatened to bear down on the Texas community. Just one month earlier Katrina had devastated New Orleans, forcing more than 150,000 people to evacuate to Houston. People were apprehensive as Rita approached. The hurricane turned and left with little damage, but not before two and a half million area residents were evacuated from their homes, making it the largest urban evacuation in US history. Residents never forgot the devastation and multibillion-dollar damages and heartbreak storms such as these brought.

Credit: GPD Group

Cooling Pavement—for People and Man’s Best Friend
Business owners like Rucker not only prepare for big storms in the Houston area, but they consider rainstorms part of life. To alleviate the stormwater that he knew would eventually hit his parking lot at the Spring Street Beer and Wine Garden, he hired Texas Eco Pavers to install pervious pavers in the 7,000 square feet of parking and patio areas. Brown, an installer for TRUEGRID, brought in his local crew to begin work on the Houston venue.

“It took two days to excavate, two days to install the gravel, one to lay geogrid, and one to spread the black star gravel and apply the SuperSpots,” says Brown. “Altogether, one and a half weeks, turnkey.” SuperSpots are colored markers that can be placed within the TRUEGRID matrix to delineate parking spaces, traffic lanes, fire lanes, or other spaces.

“The whole parking lot is installed with TRUEGRID Pro Plus, and we have a few walkways done with TRUEGRID deck and deco products,” says project manager Derek Schutz.

Credit: GPD Group
The Flats East Bank in Cleveland

TRUEGRID is used in a variety of commercial applications including parking lots, storage yards, roadways, and drive lanes. Made from 100% post-consumer recycled HDPE, the interlocking grid units are just under 2 inches deep. The round stabilizing grids need no staking or clips and can be cut with a saw. Once the units are put in place they can be filled with gravel.

In an effort to make patrons more comfortable, says general manager Sonia Thornhill, Spring Street Beer and Wine Garden decided to add other structures even after the installation. “We built another pergola for shade. It was on the side with the TRUEGRID so we had to do a few changes, and it was very easy to modify.”

Brown and Schutz together detailed the entire installation carefully. “For this installation, we received the project during the design stage of construction.”

Using a Bobcat T590 skid steer, they first excavated 8 to 10 inches across the entire lot where the grids would be installed. Excavating with a track loader works better than using a wheel loader, says Schutz.

“Here in Houston, the ground is tough clay to a sandy soil mixture. We next compacted the ground with our Wacker Neuson RD28, an articulated tandem axle vibrating roller,” he explains.

Using 6-inch galvanized timber tie nails with roofing insulation disks, an 8-ounce nonwoven geotextile filter fabric was secured in place. Six hundred tons of 1-inch limestone (#57) was compacted across the lot using a Wacker Neuson roller. The lot was then ready for installation as soon as the TRUEGRID Pro Plus units were delivered.

“This gives the 40% void space that the city has approved as the appropriate detention required per square foot of impervious coverage,” says Brown. “We began laying down the grid, one piece at a time, using four to five workers, until all the grid was interlocked together.”

TRUEGRID provides optional SuperSpots to distinguish specific areas of a site. For the Spring Street Beer and Wine Garden, blue and white SuperSpots were installed to mark nine 9- by 18-foot parking spaces for patrons.

After the site was leveled and compacted, 100 tons of 5/8-inch black star gravel was spread using the Bobcat and a 72-inch broom attachment. This allowed the rock to be swept deep into the cells until it was flush.

“We install with a slight overfill,” notes Schutz. “In the first six months, you will see the gravel recede into the cells due to driving, walking, and rain. This is ideal, as you want the load to be on the grid and not on the rock. The rock acts as a stabilizing component and strengthens the overall grid.”

With the detention capacity under the parking lot and patio areas, Rucker was able to utilize 100% of his land with no need for a separate detention pond. The TRUEGRID area counted as 100% pervious cover; by not adding to the amount of impervious cover, it minimized the necessary stormwater detention needed on site.

The Harvey Test
Rucker notes that Hurricane Harvey sat over Houston for some four days, dropping an estimated 1 trillion gallons of water. “During Harvey, we were really concerned about the flooding. Water was rising about a block away from the property. It was just pouring down. But it [TRUEGRID] just performed and did what they said it would do.”

During the hurricane, the water delivered to Houston could have covered Harris County’s entire 1,800 square miles with 33 inches of water—all at once.

“It rains here in Houston,” says Thornhill. “This year, it’s been all the time. But it doesn’t just sit there in the parking lot anymore. As soon as it rains, someone walks out and is surprised that there’s no water.”

She adds, “We have a dog-friendly patio and the dogs love it because TRUEGRID isn’t hot on their feet; and its cooler on their foot pads. And the guests love it. Cement gets hot, you know? Down here, people go barefoot a lot, so it’s great for people and for their dogs.”

Credit: Texas Eco Pavers
Parking area with SuperSpots to mark spaces

Cleaning Up the Wabash For the Long Term
Construction of a mile-long stretch of a new 72-inch-diameter sewer through a 100-year-old section of Lafayette, IN, presented the city with an opportunity to improve not only the quality of the water reaching the river but also the appearance of the neighborhood.

The Brown Street project is part of Lafayette’s $179 million Combined Sewer Overflow Long-Term Control Plan (CSO-LTCP) to reduce raw sewage overflows and to improve the water quality of the Wabash River.

“While the driver of this project was the CSO-LTCP,” explains Tim Healy of Greeley and Hansen, the engineering firm hired by the city, “we knew the project would require disturbing the entire Brown Street right of way. We had to look at how we can put it all together in a way that’s aesthetically pleasing and functional for the community.”

Credit: Pine Hall Brick

Lafayette has more than 72,000 residents and is one of 100 communities in Indiana with combined sewer systems that collect and amalgamate residential sewage, water used in commercial and industrial processes, and stormwater in the same pipe system. In periods of dry weather, the pipes transport the water to a wastewater treatment plant, where it is treated and later released to the river. However, during a storm, the conveyance capacity of the system can be exceeded, resulting in a CSO situation.

Developed to address the Clean Water Act requirements, the 20-year CSO-LTCP will also provide long-term benefits for residents of Lafayette by reducing overflows that can cause flooding and basement backups in wet-weather events, in addition to improving the river, which is becoming an increasingly vital part of the community for recreational use.

“Lafayette has a conventional activated sludge treatment system with chemical chlorination and dechlorination and phosphorus removal,” says Brad Talley, superintendent of Lafayette Renew, formerly the city’s Water Pollution Control Department. “The biosolids are then land-applied.”

Lafayette currently has 10 overflow points, says Talley. In an effort to reduce the estimated 96 annual overflows, the city upgraded its wastewater treatment plant in 2000. The $60 million expansion has increased the treatment plant’s wet-weather flow treatment capacity from 22 million gallons per day (mgd) to 52 mgd, enabling the plant to treat additional flows. This improvement has reduced the number and volume of the community’s CSOs.

The Brown Street Sewer Project was part of the CSO-LTCP and was essentially constructed to store and convey wet-weather flows from Brown Street to another upgraded lift station. The city was eliminating an old lift station and, as part of that plan, constructed a 114-inch-diameter storage and conveyance tunnel that would move flow from the old station to the Pearl River Lift Station.

“Brown Street now connects directly to that tunnel,” says Healy.

The tunnel provides conveyance to the Pearl River Lift Station, but just as importantly, the large-size tunnel acts as wastewater storage.

Lafayette Renew hired Indianapolis-based Bowen Engineering as the general contractor for the project and engineering firm Greeley and Hansen to develop the best approach to incorporating green infrastructure for Brown Street. Green infrastructure features previously used included dry wells, rain gardens, storm parks, and permeable curbs and alleyways.

Along the length of Brown Street, a 72-inch sewer pipe was installed using open-cut construction, disrupting the entire width of the street. However, the city realized that the required conveyance sewer provided an opportunity to make aesthetic contributions to the neighborhood.

Brown Street, with a 38-acre drainage area, has high infiltration rates, up to 80 inches per hour. One of the options considered by the design group included dry wells, but these contributed nothing to the atmosphere of the community. Permeable pavers, on the other hand, were attractive and had the desired functionality. PaveDrain, distributed in Indianapolis by D2 Land & Water Resource, was selected as the appropriate permeable paver for the roadway. PaveDrain, based in Milwaukee, WI, has distributors across the US.

D2 Land and Water Resource installed approximately 36,500 square feet of PaveDrain pavers over a prepared stone bed.

“There are no storage tanks or pipe under the PaveDrain. It’s all stone,” says Healy. “When they installed that sewer pipe, they put stone all around it, and with such great infiltration rates, it essentially created a drainage system.”

Credit: Tim Healy, Greeley and Hansen

He adds, “The small excavator has a specialized arm that can pick up an entire layer of block from a pallet very quickly set them in place. The installers then use a rubber mallet to pound them in place and quickly move on.”

Geotextiles were used as base reinforcement and separator layers. Stormwater transfers directly through the pre-designed spaces between the blocks and into Brown Street’s rocky underlayer.

Permeable paver parking lanes border Brown Street’s asphalt vehicle lanes. The color of the pavers in the parking lanes help make them visible and distinguish them from driving lanes.

Credit: PaveDrain LLC
Brown Street inLafayette, IN

“For Lafayette, there’s no media or engineered sand between the PaveDrain blocks. The city wanted something they could standardize for future use,” says Healy. “The water and sediment go down to the soil or it stays in cracks between the pavers. Then during maintenance, it’s cleaned out with a vac truck.”

Lafayette Renew uses a cleaning mechanism (PaveDrain vacuum head) twice a year to do maintenance on the pavers. The city has stopped using sand during winter months along Brown Street and now uses salt for deicing, because it doesn’t collect in the gaps between pavers but is diluted and washed down with other debris.

After the Brown Street project was finished in 2017, the city used a fire truck to try out the new pavers, dispersing 2,500 gallons of water at full blast onto the pavement. It drained off almost immediately, notes Healy.  SW_bug_web

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