Changing Planet

In Defense of Greenspace

Maryland’s Capital Crescent Trail–is it parkland or a transportation corridor? (Credit: Dan Klotz)

Tuesday, November 17, is the deadline for proposals to knock down hundreds of trees and pave over a stretch of the popular Capital Crescent Trail in Montgomery County, Maryland.

If that sounds kind of backwards, well, it is. The planned conversion of a greenspace corridor into a transportation corridor—for the commuter train system called the Purple Line—is taking place even though the land is flanked by two active transportation corridors, the I95 Beltway and the East West Highway, route 410.

But the thought of adding the Purple Line to either roadway and altering car traffic patterns was deemed unnecessary, given that the greenspace was just sitting there.

Officials in Maryland of all stripes—from the counties, state agencies, and the legislatures—are unable to look past the origins of this greenspace. It was once a one-way rail line for freight trains, not even wide enough to fit a second set of tracks for the return trip. These officials have insisted that it is still a viable transportation corridor. It is after all one of the more heavily used bicycle paths in the country, one that I use in my daily commute. But that’s not what they mean, of course.

To them, it’s still meant to be a place for trains; despite the Capital Crescent Trail’s popularity, no one ever updated the government maps to reflect reality. And this is a region that was once praised for how it values parks.

Choosing cement over trees and prioritizing cars over parkland is a textbook symptom of suburban sprawl. The value of greenspace, especially in urban and suburban locations, has often been overlooked. Parks are always expendable, prime targets for infrastructure development.

Several years ago, for example, New York City decided to build a massive filtration plant for its drinking water system. It had two choices: build the site on an unused industrial plot in the suburbs just north of the Bronx, or build it in the Bronx—within city limits—at the site of the only municipal golf course located next to a stop on the subway system.

The builders chose to dig up the golf course. Even though the City installed a new course on the roof of the still unfinished plant, the neighborhood impact has been tremendous and the loss of trees, irrevocable. It’s also been noted that the fairways of the new course are too narrow, and a different experience than the previous course.

Shortly after these plans were finalized, the Trust for Public Land (TPL) released a report quantifying the value of urban greenspace. In looking at Washington D.C., just below the planned Purple Line route, researchers found that the DC government collected almost $7 million more in property taxes in 2006 because of its parks and greenspaces.

Researchers have also found that urban parks and greenspaces improve the health and wellbeing of residents. The TPL report mentioned above found that the city of Sacramento lowered its healthcare costs by almost $20 million in 2007 because of its parks and greenspaces.

The concept behind the Purple Line, having a part of the Washington DC Metro rail system that connects the suburban region, is certainly laudable. A functional mass transit system is an important component of a healthy, modern metropolis. But so is greenspace. The choice between parkland and transportation is a false paradigm. Both are equally important, and one should never be sacrificed for the other.

Residents are supposed to appreciate that the plans call for adding a bike path next to the train tracks. We’d rather keep what we have, though—especially the trees. It’s healthier.

The destruction of the Capital Crescent Trail is not the only problem that the Purple Line spawned. To the east, the railway will exist alongside major roads—but advocates from the working-class communities that would host the railway call the plan disastrous. Their concerns—from unsafe pedestrian crossings to noise and stormwater issues—could be alleviated if the line was simply built underground.

An underground train line would eliminate almost all of the Purple Line’s impacts and disruptions along its entire route. It would preserve greenspace and the character and safety of the neighborhoods bordering the route. But placing the train underground would also cost more money, and the government is trying to do this as inexpensively as possible.

A nice idea done on the cheap provides bad solutions, oftentimes much worse than the original problems. The Purple Line is no different. It would be much better to scrap the current plan and figure how to do it right rather than to pave over greenspace and permanently plant more suburban sprawl.


Dan Klotz is a veteran writer and advocate on conservation efforts and the health and sustainability of our food systems. Dan's career has spanned a wide range of policy issues, including protecting sharks around the world, securing the land rights of indigenous communities, addressing the sustainability and research needs of agriculture both domestically and internationally, advocating for smoke-free workplaces, cleaning up toxic waste sites, and preserving wild areas on land and in the ocean.
  • Pam Browning

    This is so true. The Purple Line route on the Capital Crescent Trail was chosen because this greenspace was considered expendable. The value of this wooded trail was never weighed in the Environmental Impact Statement, despite the fact that the CCT is the most popular trail in Maryland.

    Tens of thousands of Trail users signed petitions, testified, wrote letters — with no acknowledgement from transportation officials.

    Communities across the Country work hard to try to create linear parks like the Capital Crescent Trail. And yet, Maryland and Montgomery County have turned a blind eye to the value that this unique, contiguous, nature corridor provides to the environment, wildlife, and the mental and physical health of trail users.

    Putting transit on the Capital Crescent Trail sets an alarming precedent for other trails across the country that also could be considered expendable.

  • Greg Sanders

    Montgomery County, Maryland does defend green space, that’s why it has an 93,000 acre agricultural reserve and attempts to channel new residents and businesses into areas that are already a mix of urban and suburban, like Silver Spring (population 70k+) and Bethesda (population 60k+).

    The Purple Line has sterling environmental credentials, the Sierra Club has listed as one of the top 25 projects in the nation, the Washington Area Bicyclist Association endorses the project noting that it’s the only way to complete the Capital Crescent Trail and meet up with the Metropolitan Branch trail.

    Anyone remotely familiar with recent Maryland history can easily see that the idea of building the Purple Line underground is an obvious canard. Baltimore just lost its Red Line because of a tunnel span in downtown Baltimore. Instead, Gov. Hogan took the money that would be spent on mass transit and redirected it towards roads around the state. Surface light rail can connect Bethesda, Silver Spring, College Park, and New Carrollton and brings 90 thousand people within a half mile of rail transit for the first time. This matters for both environmental and social justice reasons, as commute time is critical for escaping poverty ( ).

    The mission of the National Geographic society highlights the importance of “Understanding the intricate and interconnected systems of our changing world.” This post fails that test by only considering one particular patch of greenspace in isolation from the larger environmental, economic, and societal benefits. Even considered on the test of promotion of greenspace alone, the Purple Line is a huge net plus.

  • Greg Sanders

    The Sierra Club disagrees, calling the Purple Line one of the top 25 projects in the nation.

  • Frank Lysy

    This is an excellent post. As the author notes, Maryland officials are treating the greenspace that will be destroyed by the new dual rail tracks (requiring many acres of old-growth forest to be bulldozed) as if it has a value of precisely zero. But parks such as the Capital Crescent Trail do have a value, especially in a close-in urban area such as this.

    Environmental standards such as those the World Bank (and many others) require, would call for an environmental offset for any project such as this. New park land of a similar scale and nature would need to be established near by to offset the losses. But that is not going to be done.

    It would of course be expensive. But then we would have the true cost of this light rail line. It is not the $2.2 billion capital cost that is currently projected, but something far higher. Treating the park land destroyed as if it has zero value means the true costs of this rail line are not being recognized. As a society, we ignore such environmental costs at our peril.

    This light rail line would also be a terrible use of the scarce funds we have available for public transit if one truly wanted to help the poor. The line will pass through some of the richest zip codes in the region, and indeed in the nation. And for less than half of the projected annual operational costs of this 16 mile light rail line, one could instead cover in full what is now paid in fares for the entire county operated bus systems in the two counties it will pass through. That is, one could stop collecting bus fares on these entire bus systems, for less than half the annual operating cost (net of fares forecast to be collected) of this rail line. These bus systems serve the entire counties, including the districts in the counties where many of the poor reside, and have a current ridership more than double what is projected for the light rail line (which many suspect are optimistic).

    To help the poor (and indeed all other bus riders), it would be far preferable to support the local bus systems. One could even stop charging fares in their entirety on these bus systems for less than half the annual operating expense (net of forecast fares) for the light rail line.

  • Flora Tsui

    The value of green space is non-disputable. The benefits of the purple line ar disputed by many and not supported by data or sound methodology. Green space is clearly the choice.

  • Pete Elms

    Save the trees. We talk loud about saving the rain forests. How about starting at in the DC area. We need to preserve what little greenspace we have from developers. They are the only real beneficiaries of this very expensive project.

  • Who Speaks for the Trees?

    What an incredibly short-sighted article — talk about missing the forest for the trees!

    The “inner” Purple Line, located within the close-in suburbs of Bethesda and Silver Spring, will lead to infill development and higher density in the more urban parts of DC metropolitan area. That means less sprawl, and that means fewer trees cut down throughout Montgomery County, PG County, and beyond.

    You are missing the effect of the Purple Line on hundreds, more likely thousands of times as many trees! That’s why every single environmental group loves this project.

    And really — you think the line could “simply” be built underground? With that extra billion dollars you have sitting in your pocket?

    Please, to avoid your own embarrassment — do a little research, and then write a retraction.

  • Mike Johnsen

    The EIS was done properly and, being a lifelong Montgomery County resident, I strongly support the Purple Line which will replace millions of car trips and tons of CO2 and other pollutants. The Bethesda to Silver Spring trip will be less than 10 minutes and having access to the U of MD Campus is a huge benefit to our students. Article after article is being published about how businesses need transit to attract qualified young people. We need this transit line if we want to remain competitive. There are parts of the CCT trail that will benefit from removal of trash, standing water in the old drainage ditch and invasive vines. If we don’t focus our development in our more urban areas, more acres of trees will be lost to development further out. Look at the big picture.

  • Andy

    The green corridor of the Capital Crescent Trail is used everyday by thousands of bikers, runners, and walkers. It is a key green corridor attaching Rock Creek Park to downtown Bethesda, and it’s being destroyed because the Council sees the chance for more property taxes from new density in Chevy Chase Lakes. Make no mistake–this will NOT reduce car trips; it will increase density, and density in Bethesda always means more cars. The DC area has a chance to address pollution, health and wellbeing, and congestion by just removing roads and making them paths–and yet here we are destroying a path to make a train track. There’s no chance of stopping it; County Council never met a development plan it didn’t like. It’s just very sad.

  • huskerdont

    The Purple Line needs to go back to the drawing board and be put underground. If it can’t be done right, it shouldn’t be done at all.

  • Renee Roth

    The greenspace will never return once obliterated and the Metro area needs more multi use trails not fewer. This is recognized by any person who has utilized the Crescent Trail or the W&OD Trail – on the weekend especially. The Purple Line should go right up East West Highway – it’s already cleared, it can transport people already driving between Bethesda and Silver Spring, and if the county were to close it for construction (which it often does to area roadways with no warning and no consideration for am or pm commuters) traffic would find another route and people would adapt. Why isn’t an existing road route being considered if the ultimate goal is to decrease road traffic?

    • Yeah Right

      “the Metro area needs more multi use trails not fewer.” The trail is not going away, it is being improved. Stop the fake news.

  • Mary Rivkin

    The great benefits of green space for human health have been willfully ignored by Purple Line planners. Both the MTA and Montgomery County have refused to study the risks of health, declining to conduct a Health Impact Assessment (HIA) of the project.
    Now the Montgomery County Planning Board advises, “The positive effects of parks on people cannot be overstated, particularly in urban areas,” (Plan for Downtown Bethesda, 2015). Admirably, the Planning Board wants to increase green space.
    Clear-cutting the green trail makes little sense now. We know more than we did in 1988, back when the Purple Line was first imagined.

  • Bryan McCann

    There are costs and benefits to the Purple Line, as there are to any development. I live within a quarter mile of the future Purple Line and currently commute to work by bicycle along the trail. After extensive, ongoing review of the costs and benefits of the project, I cautiously favor construction of the Purple Line, provided current plans for its design and operation are maintained. Yes, the Purple Line is both politically viable and practicable as a work of engineering because it was an active rail corridor as recently as the 1980s. Regional planning always stipulated that this corridor could be reactivated as an active rail line. Like the blogger, I love the trail as it is, but we cannot deny that the possibility of restoring rail to this corridor has explicitly been a part of regional planning since rail was temporarily deactivated in the 1980s. Building light rail along East West Highway or the beltway, in contrast–aside from presenting exponentially greater engineering challenges–is not politically viable. Building an underground rail line from New Carrolton to Bethesda would be lovely, but is not even a remote political or financial possibility. (It strains credulity that those criticizing the cost of the Purple Line suggest that an underground line–which would cost many times as much to build–is a real preference.) There was no choice of putting light rail either on East West Highway or on the Georgetown Branch Trail. The choice is between creating a new East-West public transit option or not creating one. The blogger suggests that the Purple Line will encourage suburban sprawl, with no evidence or logical explanation. It appears to me to do precisely the opposite, investing in public transport inside the beltway as opposed to new highways in Gaithersburg. Like my neighbors, I draw tangible benefits from living next to a wooded trail. But as Sierra Club endorsement suggests, the environmental interests of Montgomery and Prince Georges County at large would seem to be better served by the Purple Line. Reasonable people can disagree about the relative costs and benefits. But I do not believe this blog post offers an accurate assessment of those costs and benefits.

  • BSB

    There is one major urban biking/walking/running space that connects Silver Spring and bethesda – the trail is it. Why don’t more people bike to work in places like bethesda and silver spring? Frankly, there are few place to bike that an average person would feel safe. Why take away a trail that serves as one of the few beautiful and safe jogging/biking/walking corridors? Sure there are plenty of nice parks in MOCO, but you need to drive to make use of them and they are not on your way to work. Go figure. Point being, we should be making it easy for your average person to safely hop on a bike and go somewhere – but it’s no surprise your average person has a bike rotting in the garage. There are just few pleasant places to ride, and no dedicated bike lanes in most of both Silver Spring and Bethesda. The question should be – how can we link more people to this wonderful park space? How can we encourage new cyclists to try out a bike commute and unclog our roads while staying healthy too? I wonder how the recent bike share system is doing – where do people ride? Back and forth down bethesda lane? If you live in this area, go take a walk and compare the capitol crescent to say, the metropolitan branch “trail”. The MBT runs next to metro lines, its ugly and has a reputation for being insafe. Is the MBT the urban trail system you dream about? No. But much of the capitol crescent leg from SS to bethesda is dreamy, I mean seriously, how cool is that bridge over Rock Creek? People stop there taking photos nearly every day. Finally the latter section of this trail is horribly maintained – probably because there are plans to tear it up and put a train there. How fair is that? Put the purple line on East West and as a token, throw in the dedicated bike lane that should have been there in the first place – then all of the drivers will see first hand how cyclists are able to casually pass every single car backed up for a full half mile at Connecticut Avenue. But then agin, I’d rather be enjoying my ride on the trail.

  • Tim Choppin

    “It is after all one of the more heavily used bicycle paths in the country, one that I use in my daily commute.” What a coincidence ! I use it, too, every day. Of course, what the author neglected to say is that this part of the trail–the “heavily used” part–will be untouched by the rail project. The Georgetown Branch part is nearly unused, and that is the part that will be used, rebuilt and improved in connection with the rail project. As any environmentalist knows, the kind of greater density that an inner suburban transportation project like the Purple Line will promote is very environmentally responsible, as it redirects development that would occur in more environmentally pristine areas toward a small area that even opponents of the Purple Line in honesty should admit is environmentally compromised. I’ve pointed out just one misstatement of fact in this piece. There are several others just as egregious, such as the claim that the right of way is too narrow for two tracks. This is a very, very shoddy and misleading blog post.

  • BTA

    The corridor has always been preserved as a rail right of way. What is anti green is not taking hundreds or thousands of polluting cars off the road every day. Talk about backwards priorities.

  • Robert Posner

    Unfortunately, the Sierra Club’s endorsement was premature. I am a 65 year long member. The Final Environmental Impact Statement identified the resulting Capital Crescent Trail as tree less and with two tracks alongside a concrete slab substituting for the natural beauty of the tree lined and heavily used Trail. And the Trail is a 19 acre urban park that is heavily enjoyed by walkers, runners, bikers and strollers. Tunneling is a viable option..given the costs of major bridges over Rock Creek, Jones Bridge, Connetticutt Avenue and a 4 elevator capacity shaft to connect to the Bethesda Metro, detour to avoid affecting the golf course, several pedestrian overpasses overpasses, no foundations underground that impeded tunneling and the decrease in property value (15% to 20%) of residences bordering the PL right-of-way. And the value of the Trail in terms of health, recreation and nature closes the gap between surface and tunneling.

  • Norman

    I wonder how many people posting comments here have actually been on the trail where the PL is being built. It would seem not too many. As an avid biker/walker/runner on the CCT, I fully support the PL.

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