We can’t take our water supply for granted
by Erik Ness
The operations center for the Madison Water Utility doesn’t exactly have a panic-room vibe. Large windows overlook the lawn and trees of the Alliant Energy Center. There are more than a dozen monitors showing security feeds, chemical levels, truck locations and key-card swipes. Two idle screens feature – really – cat pictures.
But the four monitors that track the heart of the operation were blinking an urgent green last summer as the hot drought of 2012 stretched on. Every well but one – in Olbrich Park – was tapped. The single-day pumping record of 2001 had not yet been reached, but day after day the city was drawing about 50 million gallons, compared to an annual daily average of 29 million. Only one of the city’s 22 wells has a throttle on it, which means everything was running full tilt, only one well shy of pump max.
Joe DeMorett, the city’s water supply manager, felt lucky. Two big pumpers had been out of commission earlier in the spring and had only recently come back. “Otherwise, we would have been really hurting,” he says.
But DeMorett did worry about #28, a seasonal well by Old Sauk Road. Under continuous pumping, the water levels fall below the pump, and it has to be shut down until the water rises again. “We can’t go without it,” he says simply.
Then, finally, it rained on July 18. Just 1.4 inches, but suddenly everything relaxed. Consumption dropped nearly a third in just 24 hours. A couple of wells were even idled.
DeMorett is a veteran of Madison’s water subculture. Before moving to the utility in 2008, he spent nearly 15 years as a hydrogeologist for city engineering, where he mapped pollution hotspots and dealt with stormwater concerns. And he’s game for the following thought experiment: What if 2012 were not just a historic drought, but the beginning of a trend?
It’s a bit challenging to visualize after this spring, and climate-change predictions for the upper Midwest do show us getting a bit wetter over time. But these projections are no more than particularly well-educated guesses.
Current historic lows on Lakes Michigan and Huron are being attributed to lower precipitation in the region. Climatologists also say our weather is already becoming “flashier” – more droughts, more floods, more extreme events overall. We might see more rain falling but still get less groundwater recharge.
For all of human history, Wisconsin has been water-rich. But is that the right way to think about one of our most important resources as we face an uncertain future? What if our days of water wealth are numbered?
It’s happened elsewhere. Waukesha has dangerously mismanaged its groundwater. The Central Sands region has overdrawn its ledger and faces a litigious future as it struggles to allocate water fairly to both business and natural systems. Could it happen here?
“I just have a funny feeling we’re in for this extreme weather from now on,” says DeMorett, acknowledging the risk with curiosity more than concern. He’ll play along, but let’s be clear: Right now the science says we’re okay.
“We’re sustainable right now at our current levels,” he says. “But anything changes and we’re not.”
If population goes up, if demand goes up, if recharge goes down – all of a sudden we’d be mining rather than replacing our water.
A balancing act
Madison sits atop a layer cake of groundwater. The top sheet is a mix of glacial deposits, sandstone and dolomite. Water flows easily down until it hits the frosting, a thin and less porous layer of shale. Below that is another layer of water, infiltrating the Mt. Simon and Eau Claire sandstone formations. The top and bottom aquifers are connected, but most of the city’s water is pumped from the deeps.
How do we know there’s enough? Ken Bradbury, hydrogeologist for the Wisconsin Geological and Natural History Survey, says historically that’s not been an issue. “You can drill a hole pretty much anywhere and get water out of it,” he says. “That’s kind of the mindset that much of the state has had for the last century.”
Locating a well is a little more complicated now, but he believes Madison still has a good supply. “I don’t think we’re particularly water-limited,” says Bradbury. “It would take quite a few years of consistent drought for it to start impacting the deep aquifer water levels.”
However, our current level of pumping does lower the level of water in the ground, and this decreases flows on small creeks like Starkweather and Pheasant Branch. And in the last decade, groundwater flow reversed in the central area of Lake Mendota and Lake Monona. Instead of groundwater flowing into the lakes, the lakes are now recharging groundwater. Drinking water has suffered; viral contaminants were first found in city water in 2008.
“It’s a balancing act between groundwater and surface water,” explains Kamran Mesbah of the Capital Area Regional Planning Commission.
CARPC is working with Bradbury to update the regional hydrogeologic model, a detailed computer simulation of groundwater flows they hope to finish this summer. The current model dates to 1994 and may no longer be reliable. The new 3D model can handle variations in lake and stream flows and contains more detailed and current pumping information. Local communities can use it to test well placement and pumping strategies.
Mesbah cautions that good fortune is no cause for complacency. “Being water-rich is beside the point,” he argues. “No matter how rich we are, we shouldn’t be wasting it.”
For example, only 15% of the water we use needs to be drinkable. Yet we expend enormous energy to pull water from the ground, treat it to drinking-water standards, and distribute it through the city. Then we water our lawn, which is akin to feeding high-grade sushi to the cat.
“That is an absolute waste of energy and resources and the water,” says Mesbah.
The future is purple
In 2009 the Madison Metropolitan Sewerage District gazed into its own crystal ball, imagining its business in 50 years. In one scenario staff tried to imagine a more crowded, politically complex and resource-limited future. Their top three concerns were plant location, solid waste handling and “effluent discharge and reuse.”
In all likelihood, you blanched after that last word, “reuse.” That’s what Michael Mucha, chief engineer and director of the sewerage district, calls the “yuck” factor. Effluent is what your wastewater becomes after it’s stripped of solid waste and biologically scrubbed. Effluent reuse is becoming more common in the arid West; typically this reclaimed water is shipped in purple pipes. And Mucha argues without apology that the future is purple.
“I believe effluent has a significant role to play in our water-security future,” he says. “We may have a scarce freshwater supply, and we may have to look at an alternative.”
Right now the treated effluent is released in three different creeks. What if we pumped it back upstream and fed it back into the aquifer? This ambitious idea of groundwater recharge has been kicking around for a few decades but still faces major obstacles.
First, the water needs to be cleaner. Yuck factor aside, our unmentionables are not the major challenge. Every day 112 tons of salt- the equivalent of 14 truckloads – pass through the sewerage district, primarily from water softeners. That much salt would poison the ground. Increasing levels of pharmaceuticals and personal-care products are another concern.
Removing these kinds of contaminants would take huge amounts of energy. The sewerage district and area water utilities are already some of the biggest power users in the region. Cleaning 50 million gallons a day and pumping it to Waunakee would have prohibitive economic and environmental costs.
Reusing effluent to recharge the groundwater is a conversation for another decade. For now the sewerage district is thinking about energy independence and other green technologies.
“Energy makes us vulnerable,” explains Mucha. “If we can’t pump, we can’t treat.”
Already, 35% of what the sewerage district uses is produced from sewer gas (methane), and it’s looking to expand this green energy capacity. In August, a new plant will begin harvesting phosphorus from the waste stream.
And this year the sewerage district and the city water utility will run a salt-reduction pilot project, working with a few small neighborhoods to assess new water-softener technology. If successful it could reduce how much water we need to pump at the front end and the amount of salt needed on the back end.
Promise of permaculture
As we learned last summer, the water wild card is what falls – or doesn’t fall – from the sky. Too much and we’re overwhelmed. Not enough and we pump. From postage-stamp rain gardens to acres of stormwater detention ponds, the urban environment has been struggling to deal with the challenge for more than two decades, with varying success.
Solving the puzzle has great potential. In nature, a third of precipitation filters into the ground, while the rest runs off or evaporates. The Capital Area Regional Planning Commission is tackling the project with careful community design. Combining such new techniques as bioswales and green roofs with rain barrels, rain gardens and even wetland restoration could boost groundwater by both decreasing pumping needs and potentially doubling the rate of infiltration.
But what if we took it further? Last summer, while your garden was wilting and your lawn crisping, Kate Heiber-Cobb was enjoying the lush food forest taking root behind her Monona home. Beneath the canopy of fruit trees are scores of shrubs and understory plants, anchored in a rich bed of wood chips.
Nearly 300 species bloom in her yard, but she barely had to lift a hose. The annuals in her food garden needed water – they always do – and a few new trees needed a bit of spot watering, but there was no large-scale transfusion of city water to keep her landscape alive. (She did finally empty her rain barrel into her wetland garden.) And this soaking-wet spring? While her neighbor’s yard was ponding, there wasn’t even a puddle in her orchard.
Heiber-Cobb’s secret is to mimic nature and store water in the ground. She practices permaculture, a design ethic first developed in Australia that emphasizes ecological principles.
“Your yard should be connected to your waste stream, which should be connected with your soil health,” she explains. “Your water use should be connected to your yard.”
For a permaculturist, the typical street terrace plot is an abomination, its lonely tree stranded in a turf grass desert. “In nature, that’s not how it works,” she says. There would be shrubs and groundcover plants, and leaves and twigs decaying.
We could let the Madison Permaculture Guild transform our urban landscape and its use of water. Replicate Heiber-Cobb’s backyard across a few thousand urban plots and we’ll use less water and send more into the ground for recharge. Curb cuts would lead water off the street to terrace rain gardens. There would be more rooftop gardens, more front-yard gardens, and edible trees and shrubs on the terraces and other city property.
“We wouldn’t be developing dead retention ponds,” Heiber-Cobb says. “We’d be using that water, directing it to where we’re growing things.”
Jim Lorman has been experimenting with similar ideas at Edgewood College, where he teaches biology, and in the larger Lake Wingra watershed. Myriad springs used to bubble up along the northern shore of Lake Wingra, refreshing the lake with cool, clean water. But as the Vilas and Dudgeon-Monroe neighborhoods developed, the springs faltered, and many disappeared.
Over the last 20 years this area has busily planted rain gardens, both on private land and in public rights of way. Lorman sees proof that they work every winter. For 20 years, the ice on Wingra near his lab had been solid. But around 2000, soon after a large rain garden was installed up the hill, he noticed an opening. It was caused by an upwelling spring, one he’d never seen before. It’s been there ever since. “That only appeared after we built a rain garden upstream,” he says.
Water conservation has also been a focus in local construction. The Sequoya Library, one of the city’s greenest buildings, is plumbed for rainwater to flush its toilets. (The system is currently broken.) The new Badger Rock Middle School has two massive tanks to store a year’s worth of rainwater for its extensive gardens.
But these only hint at the larger potential of green buildings. “The future lies in the creation of buildings that are regenerative,” argues Lorman, living buildings that create more energy than they consume, and gather all water from precipitation and treat it on site.
It’s only partly science fiction. Seattle just opened the Bullitt Center, a 50,000-square-foot office building that may be the most self-sufficient ever built. The technology is expensive, and in its infancy. But could it be cheaper in the long run than purple pipes?
Effluent reuse, combined with current infrastructure needs, could make for a very expensive, centralized urban plumbing project. “Maybe that’s old technology. Maybe that’s obsolete,” suggests Lorman.
When you start looking at the 100-year costs for major infrastructure projects, the cost-benefit equations may shift in favor of decentralized green buildings.
By now you’ve gotten the blue notice on your doorknob, the calls, and you’ve probably even let the meter mechanic into your basement to bring your water bills into the new century. And sometime before the end of spring, Madison residents will be able to log on and track their thirst in excruciating detail.
The new meters offer important conservation opportunities. The utility is already scanning usage stats, alerting residential customers who have been drawing water continuously for more than 72 hours – a good sign that they may have a leak. More than 76 million gallons in 2011 were thought to be lost to consumer leaks.
That’s a small leak. While the city pumps about 10 billion gallons a year, 8% to 10% of that simply vanishes. Madison’s geology is so porous that in many places leaks can just flow down, undetected.
DeMorett says that the Madison Water Utility prided itself on having the cheapest water in Wisconsin, but that it was accomplished, in part, by not replacing mains when they should have been. A recent study concluded that our 850-mile network needed to be replaced at a rate of about 1% a year to get back on track.
The new smart meters should help the utility isolate and prioritize the biggest leaks, giving a significant conservation payback.
Consumer changes happen more slowly. But water consumption in Madison has been dropping – at least, until last summer – for the last 12 years. An incentive program has replaced more than 8,400 old toilets with low-flow models. Consumers are buying rain barrels and upgrading to more efficient front-loading washers.
DeMorett thinks we’re just getting more water-conscious, and the new meters should accelerate that. For example, last summer there was no way for property owners to know how much they were using. Because meters are read every six months, the spike in use was hidden in the data. This summer you’ll be able to check how much water you used when you forgot to turn the sprinkler off before you went to bed.
More precise data also pave the way for conservation rates. Many communities nationwide now bill water use in tiers, where rates escalate as you use more water.
More planning needed
In the basement of the state Capitol building, across from the legislative aide break room and behind a locked door, is a classic fire-engine-red hand pump atop a 1,000-foot well shaft. The pump is broken, but every month Capitol workers unspool a long metal tape and measure water levels.
If you plot it out, you can see that over the last few years the water has been rising. It’s only one well in a large area, but it offers comfort to DeMorett and Bradbury.
We’re not running dry, but they also know we can improve our water management in the near term. Bradbury says his field is getting better at designing wells, placing them and pumping them. The new regional hydrogeological model he’s working on will help. “I see a lot of room for improvement,” he says.
Looking further ahead, the picture is murkier. During a crucial decade of expansion, the region operated without regional planning, and now the Capital Area Regional Planning Commission is playing catch-up. Studying climate-change adaptation has been on its wish list for a few years, but the budget hasn’t materialized.
That challenge is real, and Mesbah believes it needs to be addressed. “We are going to be in really serious problems in the next 10 to 20 years, environmentally and systemically,” he warns. “When you don’t have money you need more planning, not less planning.”
Mucha believes we need to be looking even further, 100 years into the future. Look honestly at the net value of a drop of water and “you could probably make a pretty good business case” for planning that far ahead. “But we don’t deal in 100-year return on investment,” he says.
“What happens if the drought in the South accelerates, and rising sea levels send people inland from the coasts?” asks Mucha. “Then we have more demand on our aquifers, more competition for water. If we wait too long, it will be too late.”