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Grounding Ourselves in Water
Shannon Carson
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can all harken back to memories of the droughts this past summer that
struck communities in most of the country. Lower agricultural production
affected even those people living in areas without exorbitantly low
water levels. At first glance, these extreme weather conditions seem
unpredictable and unpreventable. The truth is that ramifications of
human activity work alongside the whims of Mother Nature. Contrary
to what we have been told all our lives, people influence the weather.
The study entitled, "Paving Our Way to Water Shortages: How Sprawl
Aggravates the Effects of Drought" examines how one human activity,
suburban sprawl, takes a toll on water supplies. Put out by American
Rivers, the National Resources Defense Council and Smart Growth America,
it provides much-needed information on water supplies.
 lthough
no one asks what "sprawl" means, many people confuse it with merely the result of a growing population. But a cat may lie on a couch curled up in a ball, or it may lay on its stomach, limbs spread; in the latter case the cat is "sprawled out," or occupying a lot of space. The authors of the report define "sprawl" as "development marked by automobile-dependent, spread-out suburbs, where the activities of daily life-home, school, shopping and work-are separated by long distances linked only by pavement…" Whereas it may be perfectly ok for your cat to sprawl out, when people do they tend to affect more than the seat cushion.
 ou may already be familiar with some of the problems caused by sprawl: increased traffic, air pollution, loss of open space. But the report focuses on how sprawl decreases the quality of water because it prevents precipitation from seeping into the ground-there is not any permeable ground around to seep into-instead it runs off roads and parking lots, gathering pollutants before entering surface water.
 ut
impervious surfaces like that in driveways and roofs do more than poison rivers and oceans. Pavement precludes groundwater replenishment. As stated in the report, under natural conditions, "rainwater filters into the ground, feeding rivers through springs and seepage during dry periods, and recharging underground aquifers." Without permeable surfaces, these aquifers have nothing to offer rivers and reservoirs during periods of low precipitation.
 ome
may think, "Groundwater? Aquifers? The way I see it, the water's still getting to a river or ocean, what's the big deal?" But when water skips a step, that step loses out and so do we. Groundwater plays a vital role in the water cycle. One-third of Americans get their drinking water directly from groundwater. The other two-thirds, who depend on surface water, are implicated as well: about half of a streams' volume comes from groundwater.
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how it gets to surface water is important too. Because there is no ground to store the water immediately, the precipitation runs all the way to surface water, gathering volume and speed along the way. "The result is a decrease in groundwater flows into streams, less recharge into aquifers, an increase in the magnitude and frequency of severe floods, and high stream velocities that cause severe erosion and mobilize large quantities of sediment, damaging water quality, aquatic habitat, and infrastructure, such as roads, bridges, and water and sewer lines." Erosion and flooding are significant problems in developing areas, and no one denies that runoff is the culprit.
 he
researchers of the report found out which metropolitan areas experienced
the most development over the last twenty years. The Southeast United
States developed the most by far. Land development far exceeded population
growth-sprawl is not an issue of "more people." Researchers measured
the total area of new land development between 1982 and 1997. No area
increased development by less than 25%, and in some areas it shot
to over 100%. They calculated how much groundwater, due to impermeable
surfaces, was "lost" (and won by surface water or sewage systems)
in the top twenty developing areas. For example, in Atlanta, 56.9-132.8
billion gallons of water was lost ("enough to supply the average daily
household needs of 1.5-3.6 million people")...
he
bulk of the problem lies in transportation-related hard surfaces; they account for 60% of total impervious surfaces. This includes parking lots: "a one-acre parking lot produces 16 times more runoff than an undeveloped meadow."
he
remedy to this problem is less sprawl, or "smart growth." The report suggests smart growth techniques for future development. The authors state that over the next 25 years, 1.6 million acres of land could be saved through smart growth techniques. Smart growth involves an integrated effort to design communities differently. The ten principles listed in the article are as follows:
1) Mix land uses
2) Take advantage of compact building design
3) Create a range of housing opportunities and choices
4) Foster walkable, close-knit neighborhoods
5) Promote distinctive, attractive communities with
a strong sense of place
6) Preserve open space, farmland, natural beauty,
and critical environmental areas
7) Strengthen and direct development towards existing
communities
8) Provide a variety of transportation choices
9) Make development decisions predictable, fair,
and cost-effective
10) Encourage citizen and stakeholder participation
in development decisions
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planning from the start to diversify land use instead of just building a housing development or just a strip mall, communities ensure their own livability. Revitalizing communities that already exist reduces the speed of new development, which so often "leapfrogs" from existing towns. By diversifying transportation while incorporating close-knit concepts, people can live closer to the workplace. Less driving translates to cleaner air and water, as well as fewer groundwater-denying parking lots and roads.
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the authors write, "the old adage, 'location, location, location' applies equally to smart growth." Because different types of land perform varying functions, builders must study the area before choosing where to develop. Smart growth entails preserving highly valuable resource lands such as wetlands, forests, and naturally permeable soils, at the expense of less self-serving property.
he
authors of the report discuss the significance of natural areas currently being lost to development. Urbanizing areas often fill or bury small streams that slow the movement of water, and discharge water into groundwater aquifers when the water table is low. Wetlands, sponges that can hold up to 1.5 million gallons of water, decelerate runoff and allow water to infiltrate groundwater storage areas. They filter pollutants from the water, and offer habitat to wildlife. Despite all this, every year development, drainage and agriculture gobble up hundreds of thousands of wetland acres. The authors point out the situation of Tampa, Florida, which is now "experiencing water shortages because wetlands that once stored and gradually released water to groundwater aquifers are converted to home sites and roads." And lastly, the commonly demolished forests and woodlands store water and protect against flood; American Forests advises cities to maintain 40% tree cover.
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writers of the report urge policymakers to embrace smart growth in
order to address water shortage issues by supporting relevant legislation
and allocating resources to make it more viable. The authors even
list federal programs whose funding should increase, and press state
legislators to effect sensible land use planning. They urge them to
aid communities in protecting open space, especially critical aquatic
areas; choose priority funding areas, that are favored to relieve
state infrastructure investments; set urban growth boundaries that
prevent leapfrog development; integrate of water supply into planning,
to minimize development on permeable soils; cluster zoning to implement
standards for open space, development densities, narrower streets,
impervious surfaces; manage stormwater through onsite storage and
infiltration through permeable native soils.
his report brings to the forefront the details and research regarding how sprawl severely reduces groundwater recharge, and exacerbates drought situations. Rather than simply detail the problems, though, the report details the solution. The need to manage our growth revisits Americans every summer. Various smart growth principles have been applied in cities all over the country. American Rivers, the National Resources Defense Council, and Smart Growth America are urging us to increase these applications at the rate of development.
For more information on this topic check out the following links from some conservation and environmental groups around the country.
 American Rivers
NRDC
Smart Growth America
American Forests
Turn the Tide
Watersheds.tv
story on Chester County's porous pavement
To get a copy of "Paving our way to water shortages: How sprawl
aggravates the effects of drought", click
here.
See past topics of In the Flow here!
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