Wednesday, December 15, 2010

Getting to Know the Everglades, Part IV: Restoring the Everglades

Left - Historic Flow. Center - Present Flow. Right - Proposed "Restored" Flow
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In parts one, two, and three, as well as "The Real South Florida part one and part two, I've written quite a bit about human alterations to this part of the world.  I showed the above graphic (well, the left two panels) in a prior post, showing the actual damage to south Florida's natural hydrology.  Come to find out, the water management system (i.e. drain it all!) devised in 1890 does not meet human needs of 2010.  And of course, the ecosystem continues to suffer.  From 1948 to 2000, water usage and wetland drainage and fill were generally guided by the multi-agency Central & South Florida Project.  Its primary goals were to make sure that human needs for freshwater were met (and relatively sustainable) in south Florida.  By all accounts, it was successful at that purpose.   The cost was billions of dollars, a nearly ruined south Florida ecosystem, and a sudden realization that the whole operation was not as sustainable as they once hoped.
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So back to the diagram above.   A new Everglades Management Plan, called the Comprehensive Everglades Restoration Plan (CERP), was conceived and completed as a "re-study" of the original 1948 study, to re-assess the human and ecosystem needs for water in South Florida.  It was implemented into law in 2000 as the Water Resources Development Act, which proposes to direct 80% of available freshwater toward wildlife and ecosystem uses (I'm fairly sure this includes outdoor recreation - just a hunch) and only 20% toward urban needs and agriculture.  While this has extensive ramifications for South Florida, it's worth mentioning that the 1948 goals were devoted to providing 100% of available freshwater to human uses, including outdoor recreation, urban water supply, and agriculture.  Any unneeded water would be summarily dumped out of the canal system into the coastal bays to minimize any flood risk.  .
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The next key question is: how do you get water moving through the Everglades - a place that is barely above sea level and has less than 1% grade across several dozen miles?  And now that all those canals are built and good water is being sent out to sea, how do you stop it? The answer lies in the fact that south Florida is only level on the surface.  
Image courtesy of USGS
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Imagine the above cross-section as south (left) to north (right).  You can kind of envision this pattern by looking at the first map in this post, which shows water generally moving south.  The canal systems built throughout south Florida were cut through coral rock when needed, and dredged through sand when needed.  Throughout the system, water control structures were established to divert any needed water for human use.  So how do we start with the restoration? Blow up the control structures!
Kissimmee River Structure #65B demolished, 2000 (image: Wikipedia). Original source: likely Dykon Blasting
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Well, all you eco-anarchists out there, prepare to be disappointed..........among CERP's 200 key projects for Everglades Restoration are several dozen new water control structures.  The hope is that our understanding of hydrology in 2010 (or 2000) is vastly superior to our knowledge in 1948.  "Hope" being the key word.  Water control structures can be used to replicate natural flooding and damming patterns (temporal and spatial) in nature, which generally lead to higher quality habitat.  

New water control structure, courtesy of Ducks Unlimited
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The words "can" and "hope" can together be pretty promising or pretty worrying, depending on your level of suspicion of government agencies.  In fact, several environmental groups are very worried that the new water control structures will not be monitored adequately to ensure that a full 80% of freshwater goes back to wildlife habitat areas. Ultimately, these structures are controlled by people and/or computers that are programmed by people.  People are responsive to politics and budgets.  These are the inherent issues with water control structures.
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But concrete and pipes aren't the only way that CERP proposes to heal the Everglades - and thank God for that.  Someone, at some point, realized that since the canals are not serving doing their intended purpose (to drain the Everglades for development), perhaps the wetlands and rivers that existed historically should be restored.  Novel concept.  One of CERP's first major "re-do's" was the "undoing" of the Kissimmee River Canal.  It was a significant undertaking.
Left: Restored Kissimmee Flow. Right: Straightened Kissimmee Channel (recently filled)
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There are a set of prevailing theories used by restoration ecologists (like myself) who advocate the filling of man-made canals.  First, the removal of the canal will (by default) cause water to flow more slowly through the area.  Second, this means that historic wetland habitats will be "recharged" by the more readily available water.  Third, this also means that groundwater aquifers are much more likely to be recharged by the water that flows through the area.  More groundwater means that less surface water will have to be pumped out for human use. So what about the thousands of smaller canals?
Picayune Stand Restoration (Canal Filling) - Image courtesy of Florida State Parks
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Yup.  They can be filled in, too.  Again, the theory is that water will arrive at these spots and then not be able to drain, which will cause historic wetlands to regenerate, since water should more evenly flow across the surface of the Everglades.  Any ecologist knows it's "not that simple" and that in reality, the habitat that appears "post filling" will not resemble what naturally occured 100 years ago.  While that is highly valid and important to mention, it's also worthwhile to mention that when it comes to water conservation, any wetland is more valuable than a drained wetland.  And what of this water gently, beautifully flowing across the Everglades?  What about the roadways and railways, now critical Florida infrastructure, which run across the 'Glades?  Yes - we have arrived at a momentously great and awful monument to Everglades restoration - the bridging of the Tamiami Trail.


Proposed Tamiami Bridge - Artist's Rendition
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The briding of the Tamiami Trail - a project currently mired somewhere between litigation and full-scale construction, has become an important symbol - of what becomes feasible when we realize how important it is to care for our water, and a symbol of how good intentions can be poorly timed and even wasteful.
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The goal of this project is to forever remove the "damming" effect that elevated causeways and roadways can have when water is attempting to sheetflow across a landscape.  Project planners know that this project will be critical to have in place once the major wetland restoration projects in the CERP are completed in 2025 or 2030.  However, this is an extremely expensive undertaking (the bridge itself) and given the current state of the American economy, there are some valid concerns that for the meantime, this is a "bridge to nowhere."  It's literally not needed.  Not right now.  Of course, when you have a list of 200 "key" projects, that logic could be applied to nearly any one project due to the fact that they are all, somehow, interrelated.
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In a lot of ways, this is pretty symbolic of the Everglades Restoration effort to date.  Money is being spent.  Incremental improvements are being made.  But it's highly questionable whether anyone in politics, industry, agriculture, or environmentalist or tribal organizations has the fortitude to stick it out and deal with the pricetag, which obviously is in the billions of dollars range already.   And this is truly a "sum of its parts" effort - if it's not completed, somehow, some day, we can all be certain that no one (except the status quo) will have won.

1 comment:

Dr. Jack Share said...

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