Friday, February 22, 2013

A Drop in the Bucket...but It's a Start


Common cat-tails (Typha latifolia) in the winter marsh
I'm teaching as an adjunct at Temple University this term.  My course is undergraduate Landscape Restoration, and the class took a field trip to a wetland restoration site yesterday afternoon.

Bob Adams, Director Stewardship at the Wissahickon Valley Watershed Association, explaining the project to the students
The area where the wetland was restored had been a municipal softball field, but it was located in the floodplain of Sandy Run, an extraordinarily flood-prone tributary of the Wissahickon Creek.  Bob Adams, our guide and the Director of Stewardship at the Wissahickon Valley Watershed Association who designed and oversaw the construction of the wetland, explained that the softball field was hardly ever used because of wet soil or standing water.  So, the watershed association applied for state funding to restore the site.

Two years and $100,000 later, the 2-acre wetland was completed.  There are still problems with invasive species - especially purple loosestrife (Lythrum salicaria) - but the weevils that have been imported as biocontrols from the plant's native range in Europe seem to be reducing the vigor of the infestation.

Bob Adams showing the students a piezometer used to gauge the groundwater level
Planted trees protected from deer browsing by wire cages
We also walked to the banks of Sandy Run to look over the stream and review the challenges of trying to restore a riparian area near a stream that is so temperamental.

A tree cage damaged by flooding on the bank of Sandy Run
At the conclusion of the tour, the students left the site, but I stayed behind to capture a few more images.

The marsh in winter, partially ice-bound
Last summer's nest, probably built by an American robin (Turdus migratorius)
No one could identify this plant, but I liked its winter profile
Pussy willow (Salix discolor) wands
Silky pussy willow ovaries
Except for the electrical lines, this could be wilderness.  Actually, the site is embedded in the middle of the 'burbs.
This two-acre site represents an infinitesimally small part of Sandy Run's watershed, so the wetland can't possibly have much of an impact on the quality or quantity of water that roars through the valley after a heavy rain.  But, it broadens the riparian area, and it provides habitat for quite a few wetland-dependent species despite its proximity to a busy suburban thoroughfare. 


8 comments:

packrat said...

Really cool, interesting post, Scott. It's always great to hear about these kinds of restoration projects, though I know they can be quite a headache. Love the photos, too, especially the attractive, well-built nest.

robin andrea said...

Excellent work there. Yes, a drop in the bucket, but every drop counts.

Scott said...

Robin Andrea: Because this watershed is so heavily developed, and perhaps because two people drowned in their house's basement during one of our hurricanes a few years ago, this watershed has been very heavily studied. A recent report concluded that, if all the dozens of detention basins in the watershed were retrofitted to actually do a good job (many no longer function at all because they are not maintained), it would cost many millions of dollars and the flood heights would only be reduced by a few inches. Discouraging...

Scott said...

Packrat: The project was actually built in two phases. The designers didn't anticipate having any permanent standing water on site--it was supposed to be a seasonally wet marsh. But groundwater monitoring in advance of construction was done during one dry year (state funding constraints on the grant--naturally), and the basin was excavated too low, so the first half of the site includes the open water marsh that I photographed. They got it "right" for the second half of the project, which only holds water when there's a lot of rain. Of course, the wet marsh attracts a lot of wildlife that the seasonally-wet side doesn't, so it certainly wasn't a failure.

Doug Hickok said...

It is a wonderful project. I like the prospect of bringing more wildlife back, for me especially the birds. I wish there were more such "wild' areas restored near towns and suburbs. The good news is a remember a time when such ideas were unheard of, so we are coming a long way :^)

Scott said...

Despite its small size and proximity to dense suburban development, the site is remarkably well-used by wildlife, Doug. Last year, when I took the students to the same site, there was a Killdeer guarding a (presumed) nesting scrape on the gravel parking pad--not 10 feet from the verge of a major road.

Mike Whittemore said...

Very nice blog and thanks for the follow! BTW the unidentified winter plant above looks like it might be a Hibiscus spp. - keep up the cool posts! - Mike

Scott said...

Thanks, Mike. If the plant is a hibiscus (which is a very good possibility), it's likely Rose- or Swamp-mallow (Hibiscus moscheutos), which is fairly common in our wetlands and probably was planted as part of the revegetation effort at the wetland.