Disrupting forest ecology

NBC recently published a headline article on the root cause of the Colorado Wildfires. While the explosiveness of many fires in Colorado has been correctly attributed to beetle kill, this is really only a partial truth. Climate change is the real culprit behind both wildfires and beetle kill. The two are merely consequences of our warming forests, and the effects are likely to intensify in the future.

This is by no means groundbreaking news, but the fact that this idea is becoming mainstream is encouraging. As climate change becomes a widely accepted fact, we must acknowledge that our weather events are no longer exclusively "acts of God." What's really making wildfires worse is human distortion of natural cycles. 

Climate change creates ideal conditions for wildfire through a variety of factors. Drought weakens the trees, and stands that survive are more likely to burn in a fire (as opposed to in the past, when healthy trees withstood smaller, cyclical fires.. Drier air and hotter temperatures strengthen fires' spread. There is more dead vegetation, which is also drier, creating an overabundance of fuel. Water-starved trees cannot fight off bark beetles by producing sap, and fall more quickly to attack. Milder winters no longer kill the beetles in a deep freeze before the next season.

Furthermore, we've disrupted forest ecology through fire suppression. Trees have not only been weakened by drought and infested with beetles, but they've grown much denser than historical norms, allowing beetles to jump easily from tree to tree.

Bark beetles are natural, and their cycle is an important part of forest rejuvenation. But humans have distorted forest ecology to the point that the beetles are no longer in check, and the consequences are evident.

Today we're experiencing the consequences of climate change, beetle kill, and fire suppression all at once - like opening the Pandora's Box of wildfires.

A forest devastated by beetle kill in Colorado
Photo Credit: http://ow.ly/mqqzW

Grass values

This is a picture I took of a grassy curb in Downtown Denver, near my office. Sherman Street is peppered with sprinklers, but not all homeowners are diligent about watering their lawns.

This is one particular curb that sits in direct sunlight, unshaded by trees. A month ago, during rainy May, this patch was green and dewy. Today, it is shriveled up, after only a few weeks of the strong Colorado sun.

This begs the question - why do we try so hard to grow green grass where it doesn't belong? If this is what it looks like without a daily downpour from a sprinkler, is it really worth the effort? Not to mention the water, for a purely aesthetic feature.

Green grass is more than just a status symbol. It has become part of our cultural identity, American as apple pie. Could their be a more patriotic activity than mowing one's lawn? But turfgrass's value in our society has reached the point where it now threatens our environmental sustainability. Is it worth it, in water-stressed states, to keep our lawns green while our reservoirs dwindle?

Are dams a futile business?

California is launching the biggest dam removal in state history, returning the Carmel River in Northern California to (nearly) its original free-flowing state.

While this is a victory for wildlife and the riparian ecosystem, the reason behind this dam removal isn't so altruistic. 100 years of silt, that would normally have been carried to the ocean, has built up behind the dam, rendering it virtually unusable. Furthermore, California's Division on Dam Safety has declared the dam "seismically unsafe," meaning the communities below would be at great risk for dam failure and flooding if an earth quake were to occur.

Dam on the Carmel River. Photo credit: http://ow.ly/mghsT

The US has 84,000 dams, many of which were built in the mid-20th century in a rat race between the Bureau of Reclamation and Army Corps of Engineers. Some dams were built to enable large-scale population growth in arid territory, yet disturbingly, many were built simply to build more dams. Undammed rivers became viewed as a "waste," and we lost sight of the ecological purpose of a free-flowing stream. 

More dangerously, we saw a duty to populate regions that without massive, expensive, and probably unsustainable water projects, could not support more than a dusty little town. Marc Reisner in his monumental book Cadillac Desert, a scathing history of American water projects, chronicles this phenomenon, and it is well worth a read.

Reisner predicted our dams would eventually silt up and lose functionality. While humans can divert and disrupt natural hydrography, and perform stunning feats of engineering, it can only last for so long. 

John Sabo, a water researcher at Arizona State University, and his team conducted a study to verify Resiner's claims from 1986, the year Cadillac Desert was published. Though Reisner based his theories on history and logic, rather than data, Sabo's study found the claims to be sound. Reisner, who died in 2000, was perhaps the most clairvoyant environmental historian in our time.

What we have failed to take into account is the duration for which man can outsmart nature. We can build pipelines and dams, and irrigate the desert, but we cannot violate the laws of the ecosystem. A river must continue to the sea.

Inconsistencies in Texas

One of my favorite things to complain about is that cities don't realize how much cheaper it is conserve and retrofit rather than find new water (i.e. build a pipeline). It may seem expensive to pay residents to xeriscape and install low-flow toilets, but that's nothing compared to the task of securing more water, in a more water-stressed economy in the future, because you didn't give people incentives to conserve. It's like eating a diet of fast food instead of whole vegetables and grains because they are more expensive in the short term - heart disease and obesity will end up costing you a lot more.

Photo credit: http://ow.ly/mfdxI

So it was refreshing to see the progress San Antonio has made, according to a piece by Sadhbh Walshe in The Guardian Professional. The city apparently realized the wisdom launching a city-wide toilet replacement program, installing water-efficient appliances in order to avoid building another pipeline further down the road. However, on the whole, Texas is still trying to win with a decidedly backward attitude about water - taking other states to court to fight over dwindling supplies, rather than looking at consumption within its borders.

Fighting for scraps

Are we finally reaching the limits of human development in the deserts of the West?

With the Colorado River Basin already over-allocated, groundwater isn't much of a solution either. In many parts of the country, we've withdrawn so much that we've actually lowered the water table. Wells that once seemed inexhaustible are now churning up sand, and depletion has far exceeded the recharge rate. In fact, we're actually further limiting recharge by diverting our streams to man-made infrastructures instead of allowing water to trickle back under the ground.

Consequently, each water project seems more doomed. It's hard to sell the benefits of finding a little more water, when it has become increasingly clear that in the long run we need a miracle. Nevada's proposal for mine an aquifer along the Utah border has many residents worried, at least the ones who have thought a few years down the line.

Photo credit: http://ow.ly/mfbo9

Tom Wharton says it well in his editorial in the Salt Lake Tribute this week:

"When are developers and political leaders going to wise up to the fact that perhaps desert cities such as Phoenix, St. George, Las Vegas and, yes, even Salt Lake City may have to eventually limit growth and new home building because there simply isn’t enough water to sustain them? We see that now in Little Cottonwood Canyon where Alta and Salt Lake City are limiting development by not allowing any more water hookups."

Wharton admits his opposition is selfish, as he (and his asthmatic lungs) would prefer not to see the region turn into a Dust Bowl, as it would without its aquifers. But isn't that the point? Conservation will only gain enough momentum when people turn to it out of self-interest. It's about more than aesthetics - when the West Desert can no longer support a growing population without a significant fall in the quality of life, we will know we should have prioritized conservation long ago.

Learning a lesson about fighting wildfires

Fighting more forest fires will come back to burn us, by Michael Kodas 6/19/13

This is a model for coexisting with, and benefiting from, forest fires. The USFS is still trying to bounce back from a longstanding policy of fire suppression, and this is proof of how misguided that policy was.

"For almost 40 years now, the U.S. Forest Service has been managing the Gila Wilderness according to a “let it burn” policy that allows small, natural fires to thin overgrown forests, getting rid of dead brush and excess timber that can spark a massive conflagration. So when the Whitewater Baldy fire raged through the ponderosa pines last June, it found far less fuel, and therefore had less destructive potential, than it would have in a forest where every previous fire -- no matter how small or harmless -- had been immediately snuffed."

Photo credit: http://ow.ly/mfbEJ

After the Black Forest Fire last week became the most destructive fire in Colorado history, (the previous record-holder happened only last year in a disturbing trend), people are talking about fire. Colorado has one of the biggest Wildland-Urban Interfaces (WUI) in the country, where such a large population lives in close proximity with the forest. Fires here are a fact of life, and they will destroy property. But they don't have to be this bad.

Fire suppression, as described in Kodas' article, was the order of the day for most of the 20th century. It's another ill-fated example of playing God, much like the effects we are starting to see from a century of damming and diverting our rivers (leading to aquifer depletion, for example). We thought we could outsmart the fires, only to have them come back larger and stronger. Dry fuels and shrubs little the forest floors, having thrived without their natural predator. Now, when a fire starts, it is almost impossible to put out, raging at full force instead of a brief, cleansing burn.

Luckily, there were some forests, such as the Gila Wilderness, that escaped the brunt of this policy, and still burned with manageable regularity. Now, they provide a control for analyzing the effects of fire suppression. The results overwhelmingly favor "let it burn" over fire suppression, for the health and safety of humans in the WUI, as well as the forests themselves. If anyone is keeping track, that's another slam dunk for nature.

Photo credit: http://ow.ly/mfbOI

An excellent article article summing up the ecological damages of fire suppression was written Helen Poulos and James Workman, a fire ecologist and former firefighter, respectively, in the Los Angeles Times.

Here's a brief sequence of events -

Without fires, forests grow thick. Fuels build up and trees grow closer together, creating a fire hazard. Extra trees suck up more water, and prevent rain and sunlight from reaching the forest floor and providing nutrients to animals and vegetation below. Removing these "trash trees" would not only provide timber, but release valuable water, benefit wildlife which has suffered from ecosystem alteration, and prevent wildfires from posing such a threat to human life and property.

Manifest California

this is a fascinating bit of history, relevant everywhere but especially to my friends in California. I'm not trying to point out California as a negative example, but share more on an issue that has transfixed me since moving out west. I think many of us have no idea just how much we've altered the natural environment, to squeeze out as much water as possible to support civilization in places where it probably shouldn't belong and might not be able to last.  

__

"Everyone knows there is a desert somewhere in California, but many people believe it is off in some remote corner of the state - the Mojave Desert, Palm Springs, the eastern side of the Sierra Nevada. But inhabited California, most of it, is, by strict definition, a semidesert. Los Angeles is drier than Beirut; Sacramento is as dry as the Sahel; San Francisco is just slightly rainier than Chihuahua. About 65 percent of the state receives under twenty inches of precipitation a year. California, which fools visitors into believing it is "lush," is a beautiful fraud.

Actually, San Francisco looks green all year long, if one ignores the rain-starved hills that lie disturbingly beyond its emerald-and-white summer splendor, but this is the second part of of the fraud, the part perpetrated by man. There was not a single tree growing in San Francisco when the first Spanish arrived; it was too dry and windy. Today, Golden Gate Park looks as if Virginia had mated with Borneo, thanks to water brought nearly two hundred miles by tunnel. 

The whole state thrives, even survives, by moving water from where it is, and presumably isn't needed, to where it isn't, and presumably is needed. No other state has done as much to fructify its deserts, make over its flora and fauna, and rearrange the hydrology God gave it. No other place has put as many people where they probably have no business being. There is no place like it anywhere on earth. Thirty-one million people (more than the population of Canada), an economy richer than all but seven nations' in the world, one third of the table food grown in the United States - and none of it remotely conceivable withing the preexisting natural order."

- Marc Reisner, Cadillac Desert, 1993

Photo credit: http://ow.ly/mfbWY

False confidence

Denver is giddy after a wet May. Streams in the foothills are swollen with snowmelt, and the water level at Clear Creek White Water Park in Golden is "dangerously high," to kayakers' delight. The rolling prairie is impossibly lush, and one need not use a sprinkler to keep the lawn green.

Denver Water announced a few months ago it would implement Stage 2 drought restrictions, before an exceptionally snowy April brought many river basins close to 100%, in terms of average snowpack. Cranky water planners must have been too eager to clamp down on lawn-watering, and did so prematurely.

Photo credit: http://ow.ly/mfcgd

Yet within one week of temperatures reaching 90 degrees, browns spots have begun marring lawns across the city. The green foothills will soon return to brown, when summer trades in the rain for unadulterated heat. And the reservoirs, which are only slightly less empty than we originally predicted they would be this spring, will continue to diminish.

A near-average snowpack is not a silver bullet for our water supply. What Colorado needs is an above-average snowpack, just to make up for last summer's drought and depleted reservoirs. And then we need even more snow, to melt into water we are legally obligated to send Nevada, Arizona, and California, in accordance with the Colorado River Compact. And then we need even more snow, to fuel the population growth Colorado will see in the next few decades. And more snow on top of that, to negate the 500,000 acre-foot gap projected for 2050.

A few more raindrops in May just aren't going to cut it. 

Pipelines and band-aids

These "solutions" to Denver's water crisis get crazier and crazier. It's one thing to expect water consumption patterns can continue at the same rate as time goes on. Add population growth to the equation and it's even more laughable. But the idea that we should build a $7 billion, 600-mile pipeline through pristine habitat to allow water wastefulness to continue is a travesty. 

Photo credit: http://ow.ly/mfclO

As Chuck Howe says in his High Country News piece, the real solution "should include greater water conservation in our cities, increased agricultural efficiencies, and a more innovative approach to the operation of our water markets so that the water we have can be reallocated as economic conditions and population change over time."

The water debate draws many parallels to fracking. While everyone agrees we need to wean ourselves off foreign oil, fracking is many environmentalists' greatest fear, and not just because of the pollution, water use, and habitat destruction that accompany extraction. But because it makes us blind to the real solution: changing our consumption. 

We must ask ourselves: is buying a little extra time through water pipelines or fracking wells a wise strategy? It's as if we admit our cities have an expiration date. In the long run, does it really matter if we procure ourselves 100 more years of water, or fuel, if the problem will just come up again when that runs out? We put too much trust in the assumption that future generations will be smarter and more resource-savvy. 

We have been able to get away with driving so much and keeping green lawns in the desert because we are borrowing from our future supplies of oil and water. No matter how long resource will take to run out, if the trajectory of supply and demand will eventually converge it should not be considered a viable solution. We're spending on credit when we should only be trusted with a debit account.

Which type of conservation is effective?

This is a great Q and A with Brian Richter, a freshwater scientist with the Nature Conservancy. He makes some well-needed points about water conservation in major cities in the US, and which steps might actually make a difference.

Richter points out that recycling "gray water," or water that has been used previously for laundry or bathing, to use for lawn irrigation is actually taking that water from the freshwater source. Water that runs through our faucets and returns down the drain actually returns to the source after treatment at a municipal water plant, starting anew in the water cycle. 

However, some water IS lost through use and does not return to the freshwater source. 10 to 20% of water doesn't return to the freshwater source, and that's the water we use for irrigating our green lawns. It gets evaporated, or "depleted," as Richter says.

So while retrofitting your house with water-efficient appliances may reduce the water you use for daily activities such as laundry and dishwashing, it doesn't ultimately change water conservation, or help cities facing a water crisis unless it is so severe there is not enough water in the cycle to hold over through the treatment cycle. 

Photo credit: http://ow.ly/mfcUF

That's why cities need to focus their efforts on xeriscape. Using precious water to turn the brown prairie green is the definition of waste. Denver is without dispute running out of water, as Governor Hickenlooper's office projects a statewide gap of 500,000 acre feet by 2050. That's the equivalent of what 5 million people use in a year. Which also happens to be what the entire state of Colorado uses in a year. In forty years, we won't even be able to support the state's current population, and that's before we take into account population growth.

Leaving the tap running while you brush your teeth is one thing. Trying to turn the desert into a lush, green paradise is another. We need to wake up, and conserve where it really matters.