Tuesday, June 22, 2010

Getting Out of Town: McConnells Mill State Park

I took a trip yesterday to McConnells Mill State Park, about 50 minutes' drive north of Pittsburgh. I wanted to see what non-urban forests looked like in this area and also thought it would be nice to get out of the city for a day.

The state park is nice! In many ways the forest is similar to the ones I am used to seeing in the Champlain Valley of Vermont - with abundant oaks, maples, and hemlocks and some basswood and black cherry trees tossed in for variety. There were a few reminders that I am further south too, such as a few tulip trees and sycamores (which occur only in far southeastern Vermont) and an rhododendron in the understory.


Black cherries and other deciduous trees! There were also dense hemlock groves but my pictures of them didn't come out very good since it is DARK in there!

Black cherry bark is sometimes referred to as 'burnt potato chips'. This tree is valued by many animals which eat its bitter cherries, and by foresters and furniture makers, who value the beautiful wood in these trees. Black cherries need to grow up in a bit of sun, so their presence here suggests some sort of human or natural disturbance in the past.


This is pale touch-me-not, a relative of jewelweed. This plant likes relatively rich soils, as does the basswood that also grows in the area. Farmers also like rich soils, and most areas surrounding the park that are not very steep are used as farmland.


This is Slippery Rock Creek which flows through this canyon:


The canyon was cut about 140,000 years ago when smaller creeks flowing north were blocked by a glacier, forming a lake that spilled over a ridge. As such, the canyon is much 'younger' than the features around it (the Appalachians are a very ancient mountain range). The steep walls of the canyon are mostly forested, and within the state park.


In this way, the park is like a larger version of Schenley Park and Panther Hollow. There are of course not as many urbanized areas around the state park as around Schenley Park, but most of the flatter areas adjacent to the canyon are agricultural or pasture land, which i suppose is somewhat similar to the golf course and manicured lawns in the flatter parts of Schenley Park.


My favorite part of the park was the poorly-named "Hells Hollow" area. The only thing hellish about the area was the mosquitos - but otherwise it was a beautiful and interesting place.


Hell Run has carved its way into the rock and created a channel which actually looks like a natural version of the concrete channels of the city. It is of course much prettier, but not much absorption or filtration of water happens here!


These ripples are not in sand or silt deposited in the creek, but part of the solid bedrock in the channel! It appears that the bed of this creek is in a fossilized lakeshore or silty riverbed from millions of years ago... I had to actually touch the ripples to believe that they were solid rock.


This is a little spring that has cut its own channel out of the rock. Like all springs, this one gets its water from precipitation that soaks into the ground and/or through cracks in bedrock and is forced out later. This water probably fell as rain or snow months or even years ago. Thinking back to Pittsburgh, one of the consequences of having so much concrete (and not enough rain gardens) is that water is not seeping into springs as much as it used to.


There's also a great waterfall, which is an easy hike from the parking area.

This visit allowed me to get out of the city for a bit and experience a more 'natural' area, but it also reminded me that Pittsburgh also has a similar (though smaller) natural area right in the middle of the city!

More information on the natural history of McConnells Mill State Park is found here.

Monday, June 21, 2010

My new 'slow water' blog

I have created a new blog about my project in Pittsburgh at slowwatermovement.blogspot.com. There is no need to check both because anything I post on there I will probably post on here too. It will be more relevant to my project though, so if you like those posts, but don't want to read about Neahga turning trees into trebuchets or whatever else I post about, read the 'slow water' one instead.

Sunday, June 20, 2010

Exploring historic channels in Squirrel Hill

Yesterday I went on a mission to look for lost streams. These lost streams once flowed through the area now known as Squirrel Hill in Pittsburgh, but now are re-routed into a combined sewage-storm drain system.

The two streams I searched for are the northeasternmost in this map I posted in my last post:

Historic Drainages of the 4-Mile Run Watershed

My approximate route can be found here.

The creek 'disappears' in the southwestern corner of that route, where I started my walk (downstream/west from there it is relatively natural until Panther Hollow Lake). Upstream from here, Bartlett Road follows its course for about a block


It is hard to tell there, but Bartlett is in a subtle valley.

Murdoch street is a neat street with cobblestone and brick paving that crosses the old channel. You can see the swale where it crosses the road just north of Bartlett.


The channel followed along the current route of Forbes Road for a bit. Forbes and Murray, a major intersection where the Jewish Center and the Squirrel Hill Carnegie Library are located, was near the headwaters of this stream. In this area, the stream probably only flowed during or right after heavy rain or snowmelt.


Looking south on Murray, one of the upper channels was probably in the low spot in the distance.

The intersection of Forbes and Shady is near the watershed divide between the Panther Hollow subwatershed of Four Mile Run, and the Nine Mile Run watershed.


This photo is looking east. Anything over that rise historically flowed into Nine Mile Run instead of Panther Hollow. The underground 'sewershed' is approximately the same to this day.


This little divide on Shady Avenue near Aylesboro Avenue represents the old divide between Panther Hollow and an apparently unnamed little creek that drained the area to the north.

This creek started out flowing down Solway Street.


Solway Street has a lot of open lawns and could be a great candidate for rain garden installation... but many of the garages on the north side of the road, near the original channel, are sunk into the ground, so it would be necessary to make sure flooding wouldn't affect these areas due to poorly designed stormwater management structures.

At this time storm clouds started gathering...


Wightman Playground at Wightman and Solway is sunk into the ground, and appears to be part of the old creek valley.


To my surprise, along the old channel I found one of my old enemies - a tamarisk plant! This plant causes a lot of problems in waterways in the Southwest, and there is a lot of debate over what should be done about it. In this case, the channel is long gone, so the tamarisk can't do anything to it. I doubt it is invasive in Pennsylvania anyway.


Since it isn't displacing native species or salting up the soil in this case, I can look at it notice that it is actually quite pretty. I still had to control an urge to go chop it down.

This channel then used to shoot down a canyon that Beeler Street is in now. It is still steep enough that you can get a feel that it used to have water flowing through it. The whole thing shoots into Carnegie Mellon, which I will explore later.


I walked back to my starting location along a small historic channel that used to shoot up Forbes Street.


In this channel I found... WATER! It turned out that it appeared to be from over-irrigation of a lawn.. but there were some signs of seepage along Forbes Road that could indicate the water table is still near the surface here.

Near the golf course I found a tiny channelized 'stream' with erosion deposits.


I imagine with some sort of modifications, this could possibly be naturalized a bit more... at least slowing the water down before it shoots into the nearby sewer drain.

I made it home before the gathering storm hit. It was another impressive thunderstorm with lots of cloud to ground lightning so I am glad I didn't decide to weather the storm in the park, which I briefly did consider.


The storm seemed significant enough that it probably caused yet another sewage overflow event to occur.
After the storm cleared there was a nice sunset. You can see another storm way off in the distance; that storm did not hit Pittsburgh and went somewhere to the north instead.


So... what is the future of these lost drainages? They are going to have to stay lost for the foreseeable future, since Squirrel Hill was built right on top of them. If you live in this area, you won't be able to see these lost streams again, but you can still restore some of the 'micro hydrology' of the area by building a rain garden or other water art that allows rainwater to percolate into the soil.

Friday, June 18, 2010

Channels of the Past

Yesterday I found a bunch of historic maps of Pittsburgh, on a Pitt site called the Darlington Digital Library . These maps, spanning from the early 1800s to the mid 1900s, showed the growth of Pittsburgh and, in some cases, the locations of waterways within the growin city. As mentioned earlier, most of the 4-mile Run watershed runoff has been routed into combined sewer-stormwater runoff channels underground. I thought it would be neat to map the old creek channels on a current map of the city, so I downloaded a USGS topo map and did just that! Sorry about the small size, the large size doesn't fit the format of the blog, so just click on it for a zoomed in view.

Historic Drainages of the 4-Mile Run Watershed

This map is inexact, of course, due to the changes in road locations over the years and just general accuracy issues (some of the old maps did not appear to be quite to scale). It gives a good idea of what the area was probably like in the past though. The dark blue streams are those that I found on the maps, and the light blue streams are additional places where water may have flowed based on the topographic map. The purple line delineates the approximate historic 4-mile run watershed, and the red line delineates two parts of the Panther Hollow watershed. I'll talk about what a 'beaheded stream' is later, in another post. The green line delineates areas of mostly natural vegetation - most of the creeks in these areas are still partially intact, except the western branch of 4-Mile Run at the far western edge of the map (more on this later too!)

So, now what? My plan for this weekend or next week is to get out there and look for evidence of some of these old channels! Most of them will be ineligible for restoration ('daylighting') due to the density of the city around them. The western portion of 4-mile run was put underground in the early 20th century when the creeks ran with raw sewage. In that state, the creek was a health risk and was buried. Now that things are a lot cleaner, there is a plan to 'daylight' a portion of this creek, if funding and political support are obtained. I'll post more about this later, too.

Monday, June 14, 2010

A Weekend of Installing Rain Gardens

So this weekend I helped a local community organization install five rain gardens in (near?) the Highland Park area of Pittsburgh.

As I've mentioned before, a rain garden is a garden intended to capture runoff from impervious surfaces like roofs and parking lots, and allow it to soak into the ground or be released back into the atmosphere. Rain gardens reduce flooding by slowing down water the way natural wetlands would, reduce pollution by naturally filtering runoff, and decrease the effects of drought by increasing groundwater recharge to aquifers that later release water into wells or springs. Rain gardens often use appropriately-chosen plants native to the local area, as these plants require little care and have the added bonus of providing habitat for local wildlife and beneficial insects.

So, this rain garden started as a small lawn:
Rain Garden 1

Note the drainspout in the background. Lawns do not absorb very much water, so whatever came out of that drainspout would rush down the hill into the gutter and then the sewer.

We now dig out an area and surround the downhill side by a berm.
Rain Garden 2

You can see that the soil is full of clay, which means it will not absorb water as readily as some other types of soil.

Rain Garden 3

We don't want to just have a puddle of water sitting there and breeding mosquitoes, so we fill most of the depression with compost or soil mix designed to be well-drained. Now at the most only a couple of inches of water would be present in the garden during very heavy storms, and it would quickly be absorbed.

Truck Full Of Soil

My truck got a lot of use this weekend!

Rain Garden 4

We next lay out the native plants, placing them so that taller ones will be in the back (just for aesthetic reasons). These plants are tolerant of occasional flooding but also dry periods, so they should not need to be watered.

Rain Garden 5

Almost done - after this we tossed some mulch on the garden and berm to reduce erosion, keep the soil moist, and decrease the number of weeds. Later on the drainspout will be connected to the garden more directly by a spout extension, or, ideally, a little naturalized swale that will also help absorb water.

Thursday, June 10, 2010

Everyone is in a watershed!

One of the things I love about runoff and hydrology is that EVERYWHERE on land is part of a watershed. When it rains, or when snow melts, water anywhere on Earth has a path it will follow, either to the ocean, or sometimes to a salt lake or salt flat. Water that falls on Pittsburgh and isn't used or evaporated ends up in the Gulf of Mexico! That is about 1000 miles by road but significantly further along the twisty Ohio and Mississippi rivers. And every bit of that huge river (except rain that happens to fall in the river itself) comes from little tiny tributaries somewhere upstream (including those that travel underground in the form of groundwater).

_DSCN1051 _DSCN1054

Water that falls on our construction materials, our parks, our rooftops, our gardens, our cars... it all eventually makes its way either to a river, or back into the air to fall somewhere else.

Yesterday I went to explore Schenley Park in the rain.

I got quite soggy, and also watched water on its way to the ocean.


pouring off bridges...


leaking out of overwhelmed storm drains...


passing through a rain garden where some hopefully soaks in and is filtered and released during a drier time into the creek...


... pausing in Panther Hollow Lake before it makes its way underground, through the sewer system, into the river.

In nature, things slow down the water on its path to the ocean, and it is used by the ecosystem, rather than just washing away. Plant roots, leaf litter, permeable soil, beavers, wetlands, numerous ecosystem components 'slow down' water before it runs off. In the city, where many of these factors are absent or reduced in scope, water just rushes away, causing floods and not sticking around during droughts. There are, however, many ways to slow down water and keep it around in the city for longer, and reduce flooding. This, in essence, is what my project will focus on this year.

Tuesday, June 08, 2010

Aftermath of Storms

Over the last week, as mentioned in the previous post, there were heavy rains around Pittsburgh. Over 3 inches fell between June 1 and June 5, with most of that in a few hours in two big thunderstorms. On Sunday I went to Schenley Park to check out the effects of the heavy rains of the last week. There had been some fairly dramatic runoff and flooding during this time.

Delta After Storm
I took a picture of this 'delta' into Panther Hollow Lake before the storms and again after. It looks smaller in the second picture because the lake level is higher. The lake had filled up well beyond its banks and almost overflowed.

Muddy Lake
When I was at the lake, the water level had dropped to near normal but was still extremely muddy. These photos are a clear demonstration of one of the problems facing this small park watershed - upstream erosion causing siltation in this lake. At some point rather soon, the lake will either have to be dredged, which is expensive, or will stop being a lake, which means people won't be able to enjoy it anymore.

Eroded Bridge
This bridge was washed out before this storm, but additional noticeable erosion had occurred during the rains.

Tomorrow more rain is expected, but without the frequent lightning and risk of hail that was experienced last week. If conditions look good, I'll be going out into the park in the rain to try to look for signs of erosion as it happens.

Building From Park
The park is pretty!

Another item of note: the atmosphere may be transitioning from El Nino to La Nina conditions. This could mean that next winter in Vermont will be much colder and icier than last winter (it may actually snow less - last winter was pretty snowy - but the snow is more likely to stick around). This would also mean a likelihood of a drier than average rainfall season in much of California. We'll see!

Sunday, June 06, 2010

Storms in the City

So, there are often thunderstorms in Pittsburgh in the early summer, and this year has apparently had even more than usual. There has been heavy rain and lightning several times since I got here. The storms aren't as impressive to see moving in as those in the desert or even in Vermont, because the sky is hazy and there are lots of trees and buildings everywhere. However, they are LOUD and the lightning is very impressive.

One storm moves away...

and another moves in. This one lasted several hours and had a ton of lightning and rain.

The storms cause lots of erosion which is a problem in the parks.

Crappy pictures of sheet lightning from my room. There were lots of crazy bolts too but not when I was able to take videos.

It looks like for the next day or two there won't be many storms, but they will be back next week, and probably periodically for the whole time I am here. This is a wet place, depending on who you ask, somewhere between 38 and 45 inches of precipitation falls here each year and the wettest months are May and June (though all months are pretty wet).

Saturday, June 05, 2010

Introduction to Schenley Park

So, on Wednesday, I went and checked out Schenley Park which will be at least the partial subject of my project. Schenley Park, and specifically the watershed of Panther Run, are the subject of a restoration and outreach project that will include habitat restoration and also will inform nearby residents on ways to reduce pollution in their watershed. Pittsburgh, like many old cities, has a combined storm drain and sewer system. This means that any time it rains more than about a tenth of an inch, all the water rushing into the sewer from concrete, asphalt, and rooftops, quickly overwhelms the sewer system and sends stormwater, along with gross raw sewage, right into the rivers. By taking simple measures such as using rainwater cisterns and creating rain gardens and constructed wetlands, residents can greatly reduce the amount of runoff after storms and thus the amount of sewage and pollution taht enters rivers. The Panther Run creek and lake act as a huge, mostly natural rain garden, and absorb much of the rain in the area that would otherwise add to polluting the rivers.

In any event, here is the park.

the top of a small creek.

Dogwood (?) flowers)

small grotto


View of the city from Panther Hollow Bridge

Small 'delta' created by erosion and runoff into Panther Hollow Lake. Part of the restoration effort aims to reduce this erosion, which is causing the lake to fill in with sediment.

Panther Hollow Lake - although this is not a natural lake, it does serve to reduce runoff and decrease water pollution.