When the Water Rises
The video below offers a quick overview of the past and present flood preparations in Grand Rapids. For more in-depth information, continue reading below.
How likely are we to get increasing levels of flooding in Grand Rapids?
Local data from the National Weather Service doesn't show a clear trend in the total amounts of precipitation that are falling in the Grand Rapids area, however, that doesn't mean that flood risk can't increase. The National Oceanic and Atmospheric Administration, the parent organization for the NWS, is expecting weather events to continue to become more severe. That means we could see bigger storms carrying more water, with drier times inbetween.
"The 2013 season was pretty interesting because we just had wave after wave of rainfall that dumped into the area," said Jared Maples, who joined Grand Rapids' NWS branch less than a year before the flooding event that happened in April of that year.
A combination of snowmelt and heavy rains led the river to crest at 21.85 feet, more than 3 feet above flood stage, causing some minor damage to buildings and infrastructure downtown and had volunteers filling sandbags to protect the Grand Rapids Public Museum, which was hosting a Titanic exhibit at the time.
There were more flood warnings in spring of 2014, as the unmelted snow held several inches of rain and temperatures were volatile, making a risk of flood if there was a sudden thaw. Luckily, the temperatures ended up cooperating and the snow melted gradually.
"It balanced out," Maples said.
In colder weather, ice jams can form against bridges and dams, and can also cause flooding. These jams are difficult to predict and require different mitigation strategies, like excavating ice with a backhoe, or breaking the ice up with augers and saws.
How well is Grand Rapids prepared for greater amounts of flooding?
"Fortunately, Grand Rapids is a city that was forward thinking and was already doing a lot of this, what we would call 'climate adaptation work'," Aaron Ferguson said, one of the author's of the West Michigan Environmental Action Council's Grand Rapids Climate Resiliency Report.
WMEAC, while not directly concerned with flooding, is concerned about the pollution that poor stormwater management can cause. Heavy rains sweep garbage and chemical pollutants into the waterways, and combined sewer overflows create massive environmental fallout. The city has taken several steps over the last few decades to mitigate both of these issues.
Late in the 1980s, the city undertook an effort to separate the stormwater sewer from sanitary sewage, preventing untreated sewage from flowing into the Grand River during heavy rainfalls. In the early 1990s, the Market Avenue Retention Basin was constructed as a part of the same effort. It can hold 30 million gallons of water, and partially remove pollutants garbage from as much as 1 billion gallons of wastewater each day, according to Mike Lunn, manager of Grand Rapids' Environmental Services.
Retention basins like the MARB can mitigate flooding by holding water out of the rivers and watershed, releasing them at a slower rate that the environment can manage. More recent additions to the city's flood mitigation plans are two stone-bottomed reservoirs that catch water and let it soak slowly into the ground rather than flushing it into the river.
In 2010, the city completed renovations to Joe Taylor Park that included a 270,000 gallon reservoir that holds and filters rainwater from about 40 acres of land. In 2016, the city finished installation of a 720,000 gallon reservoir of similar design beneath Mary Waters Park, made to serve about 120 acres, and will hopefully relieve flooding in nearby apartment complexes. They hope to continue installing these systems in the future.
Grand Rapids has also been putting work into its system of flood walls.
"We are protected to the 100-year base flood event," said Mark DeClercq, City Engineer for Grand Rapids since 2007.
In the last two years, DeClercq says the city has spent $7 million along the Grand River to strengthen and raise the flood walls and berms to at least 23 feet, the major flood level. They also spent $4 million raising the levee around the Water Resource Recovery Facility to be assured it would be protected from a 500-year flood. It was considered a necessity to keep the facility from flooding, which the WRRF is particularly susceptible to, since it sits at the lowest point along the river in the city. Recovering the facility from a flood event would be difficult, both financially and environmentally.
Where is the likely damage if there was heavy flooding right now?
During the flood of 1904, water stretched across the west side of the city, all the way to where John Ball Zoo is now. The city, recognizing the threat to its future if they couldn't keep their homes and businesses dry, began building pumps and floodwalls to keep the river within its banks. The effort continued in the 1930s through the city's public works program, when the city paid unemployed and homeless men to dredge the river and build flood walls. Regardless, in 1948 the river flooded its banks again.
During the 1970s, as part of the National Flood Insurance Program, the Federal Emergency Management Agency developed floodplain maps for use in determining levels of required insurance for homes and businesses. They show that most of the west side of Grand Rapids is in danger, below the level of a 100-year flood.
However, none of these maps takes into account any improvements since they were created. Grand Rapids has submitted its new improvements to FEMA for analysis and expects a response in early 2018.
"When FEMA approves our package then those maps will be updated," said DeClercq.
But the floodplain maps don't matter for everyone. Robin Dana owns and operates Grand Rapids Printing Company at 934 Scribner NW.
"I'm about, say, 75 yards from the Grand River, and my business is in the basement of a building," Dana said. He's been told that the floor of his shop is about a foot under the normal groundwater level. The 5,000 square foot shop has two floor drains and metal troughs along the walls leading to three sump pumps working to keep the space dry.
"If they went out, it could conceivably fill this place up," Dana said. Groundwater almost constantly seeps through the walls, only abating in the driest times of the year. During rainy seasons, the shop owner has to vacuum water away from his machines before he can keep working. In 2013, the groundwater rose with the river.
"I could see in some places where the water was normally only coming a foot and a half off the floor on cracks in the wall where it was coming four or five feet or higher draining down the wall," Dana said.
Even though he's never seen the river top the nearby floodwall, Dana struggles with his own flooding in all but the driest times of the year.
What can Grand Rapids do to further safeguard the city against flooding?
"I think there's always more that can be done, but the city is making very diligent efforts to get there." Elaine Isely said. She's the Director of Water Programs at WMEAC and also sits on Grand Rapids' Stormwater Oversight Commission, which reviews the stormwater system and makes recommendations to the city on how to modify or maintain it.
As the city refinishes streets as part of the Vital Streets Program, new roadways include bioswales that capture rainwater for trees and other plants. They also simply hold a significant amount of rainwater, allowing much of it to soak into the ground before it can flow into the storm sewer.
"That is a stormwater infiltration feature," Isely said.
Other stormwater infiltration features include 'bump-outs', grassy areas along the shoulders of roads, particularly at intersections or fire hydrants where parking isn't allowed. In fact, any green space can serve as a stormwater infiltration feature, letting water soak into the ground instead of running across paved surfaces and into storm sewers.
"In terms of the existing residents and retrofitting some of the existing buildings--there could be more done that way," Ferguson said.
While the city government has been making strides toward green infrastructure, residential and commercial buildings have been lagging behind. WMEAC promotes the adoption of green infrastructure like green roofs, porous pavement and rain barrels or cisterns. They've recently launched rainwaterrewards.com in partnership with Grand Valley State University and the Michigan Tech Research Institute to help businesses and individuals see the environmental and financial benefits of adopting green strategies to stormwater management. The city of Grand Rapids has also issued a fact sheet to help local individuals and organizations adapt their properties.
"It's education for the community," Isely said. They hope that with the benefits of adopting green stormwater management systems laid out for them, landowners will be quicker to adopt these flood and pollution preventing technologies.