Wednesday, September 26, 2012

Streetwise


The first time I visited Portland, probably 5 or 6 years ago, I came across a very nicely designed bioswale at St. Philip Neri Parish in South East. A bioswale is a specially designed stormwater catch basin with plants in it that collects and helps manage runoff. They're nice landscape features in urban places. Most people have never given it much thought, but cleaning and managing stormwater runoff with bioswales is a good idea for a few reasons.


Ok, now ignore the picture above. Picture an urban hardscape. When it rains, what happens to the water that hits your house, your sidewalks, your streets, and your parking lots? It runs off the hardscape into the gutter, right? And from there, the ordinary approaches are pretty simple. Gutters send the runoff into the city's stormwater systems, and those tend to either lead to a part of the sewage system or to simply direct the water away. "Away" tends to mean roadside ditches in less developed areas, rivers, lakes, beaches, whatever. These approaches have significant problems.

First, just directing it away doesn't slow it down. In your picture of an urban hardscape, I imagine there wasn't a lot of grass or wetlands. Part of that may be because I used the word "hardscape," but even suburban lawns don't really do the trick when so much area is covered by houses, streets, and sidewalks. Water flows over urban spaces in gravity-powered sheets of erosive energy. All the stormwater system does is gather it all into one narrow space where it can do an incredible amount of harm. 

When all that unnaturally fast-flowing water finally makes it to an outfall, out to daylight again, if it isn't straight into a body of water, it cuts through the topography like a knife. Any vegetation, native or otherwise, that might slow down or benefit from normal water flow gets torn away. What you end up with often looks like Paul Bunyan took his axe to the side of a hill, or gouged it across a meadow. Trees can't stabilize an area against that energy; they get undercut and they fall in.

If the outfall does lead directly to a body of water, you still have problems. That runoff isn't just water, it's motor oil, dirt, silt, windshield wiper fluid, dripped gasoline, soap residue from washing your car in the driveway, and a hundred other chemicals. Testing has shown that our highway system is a network of thoroughly lead-contaminated corridors. The weights your mechanic puts on your rims to balance your wheels are lead, the paint on old white-wall tires was lead-based for decades, and that nastiness (plus a whole lot more) has built up in roadside dust since the beginning of American car culture. And every time it rains, a portion of that filth gets directed right to where you, your neighbor, your uncle, or your co-worker likes to go fishing.

Where I grew up, they tended to use the sewage route tactic. So whenever it rained enough, the sewage treatment system got a huge load of extra water, often more than it could handle, and it sometimes overflowed the sewage treatment facilities. This overflow was just directed out to the beach. There were annual blooms of fecal coliform bacteria in the coastal waters, and yes, that is exactly what it sounds like. And then they still had erosion problems at the outfalls a lot of the time.

A river full of poo-slime

Bioswales, though, catch that water and slow it down by design; they're shaped for retention and slow discharge. While the water sits there, the sediments and a good deal of the contaminants can drop out in a confined, maintained, cleanable space, rather than getting sent "away." The hardy, native plant species adapted to the region, also slow water flow, and get something like an inundated wetland habitat for a time. In addition, the plants themselves are chosen for their ability to take up and/or filter out a lot of contaminants, including oil. Once all this has happened, the water flows into the stormwater system clean and slow.

So bioswales are important because they lighten and spread out the load on stormwater and sewage systems over time to reduce overflows, they recharge the groundwater, and they clean the runoff before it even gets into the system. All of that is aside from the fact that they can also be very pretty, and make me feel proud of my town for its forward-thinking development. I was lucky enough to have the opportunity to go volunteer at a planting in a rather large bioswale adjacent to the Willamette Park boat ramp, recently, and got a few really nice photos.

Me & the kiddos volunteering

Yes, this is another "I love Portland" post. See, Portland has these things all over the place. They're outside my grocery store, in front of houses, and on major thoroughfares. There's actually a suggested bicycle route you can take to check out a large number of them on the east side of town. Portland even has a volunteer group that goes around taking care of these things, picking up trash that gets washed into them, raking up leaves that'd otherwise clog the drain, or even watering the plants in the dry season to help them thrive.

The volunteer Green Street Stewards program has a maintenance guide and formal training events. There are two trainings left this season (one morning session on the 29th of this month in SE, one evening session on the 3rd of next month in NE), and they need all the help they can get. Go sign up. Do some good for your wonderful City, and feel good about investing in your town.

Saturday, September 8, 2012

Lords of Nature

Lords of Nature is a great documentary I got to watch for a grad school class once.I really thought it was worth sharing, but it apparently isn't free, so all I can do is tell you about it.

Now, many of you may be aware of the idea that predators regulate the food chain. For example, if for some reason the rabbit population booms, rabbits become easy to catch, so the fox population booms, too, with a slight delay. The boom in foxes causes the rabbits to decline and crash, which means rabbits are harder to catch, so the foxes decline in turn. This is pretty well established ecological theory nowadays.

The Basics.
 
Another well-established facet of ecology, only slightly more advanced, is the Keystone Species idea. Keystone species are those that have a super strong influence not just on a single species, but on whole systems they occupy. Like an arch, if you remove the keystone, everything crumbles. This theory was born from the work of Robert Paine in 1966. What Paine did was remove sea stars from small patches of tidal habitat that were full of life. In these areas, sea stars were the top predator of all the different limpets, bivalves, barnacles, and other critters there. When the sea stars were removed, the diversity of species in those patches plummeted. The presence of the predator opportunistically picking off prey allowed many species to flourish, and its removal allowed certain species to out-compete others and basically take over.

Lords of Nature is about that dynamic, with wolves as the main case study. See, for decades, wolves had been gone from Yellowstone Park. They were hunted down and run almost entirely out of the country under the theory that wolves are bad, so we don't need 'em. They're "bad for agriculture," "bad for ranching," and keep populations of big game hunting species like elk and bison down. So, like mountain lions elsewhere, wolves got hunted down and killed en masse, with government bounties for carcasses. In the 1870's the wolf population of Yellowstone was around 300-400 wolves. In 1924, it became zero, and it stayed that way for decades.

In those decades, Yellowstone stopped . . . working. The elk population exploded, naturally, but the consequence of that was that they were eating, eating, eating. Riparian vegetation, usually not overgrazed because deer are cautious when going out into the open, pretty much vanished. This has major consequences for how rivers work, how banks are stabilized, how other species can use the river, and everything in the riparian systems began to degrade. Young trees got overgrazed, too, and couldn't grow to adulthood, so the famous Yellowstone forests just aged, and mature trees died without propagating.

Biologists were concerned about this and unable to understand why the forest was aging and why the riparian systems were degrading, until a couple of them, Bob Beschta and Bill Ripple of OSU (Go BEAVERS!) did a little thinking and figured out the connection: Yellowstone ecology started going sideways when the wolves were extirpated. They got in one of the coolest academic article titles I've ever seen. Wolves and the Ecology of Fear: Can Predation Risk Structure Ecosystems? Their 2004 paper suggests the answer to that question is yes. Wolves got reintroduced in 1995, and since then everything has begun to recover in very cool ways. There's a good writeup on the whole case study and relevant concepts here, for those who are curious.

Anyway, the reason all this with the documentary and the paper from 6 months ago and the comes to mind is a recent news article in the Oregonian. Apparently, the Eagle Cap Wilderness around the Minam River in eastern Oregon is now home to a new pack of wolves, and the latest count is that 23 pups were born in Oregon this year alone! I'm pleased to say I have a small amount of familiarity with that part of Oregon. The work I did monitoring salmon habitat earlier this year was in the adjacent watershed. Though I never visited the Minam specifically, I was all up and down the Upper Grande Ronde and Little Catherine Creek, just a hop, a skip, and a jump from this new wolf pack, and from what I've heard of that watershed, it's one of the most pristine areas in the state.

I hope I've impressed on you why this is such good news. On levels we're just beginning to understand, wolves make forests and rivers . . . work.

My Tropical Rain Forest Canopy Walk

Yes, I can say I visited a tropical rain forest and walked through and out over the canopy. I didn't get to work in a tropical raindorest, studying nocturnal forest mammals or mapping the range of some endangered flower, but I DID hike and sweat. Let tell you about Kakum National Park, in Ghana.

I was in Ghana to support a school for the Deaf there. My wife is an interpreter and we've volunteered and worked for the Signing Time Foundation for over two years now. So after working with them for a while, we got invited to join STF on a trip they were making with Signs of Hope International (another incredible organization you really should consider supporting) to visit and support the first school for the Deaf established in Ghana.

The fundraising for the trip was a nightmare, but we raised enough to get to go, cover our transportation and room & board for the trip, AND cover the tuition and room & board costs for a two kids at the school for about 5 years each. I did all that fundraising not knowing I'd get to visit a genuine for-reals tropical rainforest, but I'd have done it just for that, honestly. My wife's travel journal for the trip is here, if you'd like to read and see some videos.

So anyway, the trip coordinator makes a point of having all Signs of Hope travelers swing by a few stops besides the Deaf school. One is the nearby outdoor marketplace, a maze of outdoor tented stalls selling everything from household staples to electronics to local artwork. Another is the Cape Coast Slave Castle Museum, a place where the weight of history threatens to crush your faith in humanity. And there's more, but my favorite is Kakum.




Ok, now, to understand the joygasm I had there, you have to get that I've been an environmentalist since I was a child. I had all the hippie talking points on rain forest clear-cutting down by middle school. I confused my parents to no end, but that was just me. Let me describe this a bit more.

We rolled into Kakum and then we hiked. Up. It was hot, it was sweaty, and it was gorgeous. The canopy was thick, cicadas were buzzing all around us, and the tour guide would stop periodically to tell us about this or that tree or historical feature, the time he and some tourists happened upon the rear end of a spitting cobra just laying there, front half in a burrow, alive and dangerous, but unmoving and unbothered by their presence, et cetera. We got to the top of this hill and found a structure that looked like the beginning of Disneyland's Jungle Cruise ride. The lower level was just a spot to sit while you wait your turn, and the top was the beginning of the rope-bridge canopy walk.

We stepped out onto this bridge, and began our horizontal trek outward, through the canopy. Because the rope bridge began at the top of the hill, every forward step brought us further out of the canopy as it descended with the terrain. Birds flew past us, insects the size of our hands just hung there in places, and the noise was incredible. And then, at some point, we were just out past and above the canopy, looking down on it, with no way to visually understand just how high up we were. I was in heaven, ladies and gentlemen. Heaven. My group was all busy taking pictures of each other on the rope bridge, amazed by the height, enjoying the beauty of the place, but somehow not entranced in the same way as I by the rain forest itself. I wanted to KNOW everything about how the ecology of the place worked from roots to leaves, eggs to bugs, nests to territories. Incidentally, if anyone knows of any particularly good reading material on the topic, I'd love to hear about it in the comments section.

I got back to our hotel that night after a 6 hour ride in an old, cramped, rickety passenger van they call a Tro-tro. We were fed the same food we'd been eating for the whole trip, the water in our hotel was shut off so we couldn't shower, and the power was out so we ate by candle light and hung out in the common room with a single flashlight upright on the table to see our companions by . . . and I was still exhilarated. I jokingly told the group that I wanted to go home and show my kids Fern Gully (not the finest moment for Robin Williams or Tim Curry, but fun, and set in a rain forest).

Here's another video with a little more perspective on the height and structures we were experiencing.


 
If I ever get to go back to Ghana, I'm going to spend more time there, and see if I can find a group to volunteer with for research or restoration purposes. So what about you? Have you ever walked through a rain forest? Or maybe arctic tundra was your coolest ecology experience? Deep sea diving? Share with me!