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Holland Run Gap - Marple Twp, Delaware County, PA

Siltation and its effects (photos below)

The photos below are for informational purposes and illustrate the issue of chronic siltation and its effects in Holland Run (aka Hotland Run) in Marple Twp, Delaware County, PA. The photos shown here span five years (2003-2008) and were not part of a planned project, but were recently assembled from all those I've taken in the Holland Run watershed and together tell a story about siltation and its effects.

Siltation is only one kind of issue affecting this and our other few remaining wild places in Delaware County. The lack of stewardship for this stream and its watershed is illustrated by the siltation issue, but overall watchfulness for all of Delaware County's small streams and springs should be the issue to consider. Protection of our natural resources is a community responsibility.

I only recently learned that in the fall of 2007 "Hotland Run" was given recognition by PA DEP as the County's **only** Exceptional Value stream. A previous survey of natural areas in Delaware County by the Nature Conservancy also noted the uniquely pristine and relatively undisturbed nature of this place, including many old beech trees. I've spent hundreds of hours in DelCo woods and I think this place is unique, too.
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Holland Run is a small spring-fed stream that meanders downhill for about a mile from its sources to empty into Crum Creek just upstream of the Geist Reservoir. From its junction with Old State Road the mainstem can be followed upstream adjacent to Marple Woods Drive, past the condo development, and continues upstream to a cemetery at the head of the basin. There are remnants of a colonial-era settlement and springhouse near the top, and some very large trees. The outlet, or mouth, of Holland Run can be seen along the stretch of Crum Creek Road between the Old State Road bridge and where the road goes under the Media Bypass bridge. Geist Reservoir is owned and managed by AQUA PA, and serves the water needs of an est. 750,000 people. The biggest issue affecting the reservoir is - siltation.

I refer to the Holland Run watershed area as a 'Gap' - emphasizing that along most of its length Holland Run drains steeply sloped woods on both sides, giving the place a 'canyon' feeling. This is especially noticeable on a foggy spring or fall morning, or when the watershed is blanketed in snow.

Like many small streams, Holland Run is also 'flashy'. That means that the stream responds very quickly to a rain event, rising fast and then dropping just as quickly when the rain stops. To see the siltation involves being there when it happens; an hour after a storm ends, the stream can appear to run clear.

The effects of siltation were noted before any sources were identified. There have been multiple sources, not just one; some are short-term (weeks-month) transient construction events that impacted the stream heavily for a time, and others are chronic silt sources. I first noticed very few 'top of rock' aquatic insects in some sections of the stream, and instead increased layers of silty detritus. Occasionally when I would visit the gap on a day after a storm I'd find cloudy pools that later settled into a fine silt coating of the substrates. Dead stream creatures began to appear after storms, too - frogs, crayfish, and an unusual salamander. For a time I was sure that minnows had became harder to find in most of the basin. It wasn't until I visited the place *during* a rain storm that I understood the observations I had made.

*Note - The text of the first version of this page and its associated image pages was a bit 'dramatic' in tone. Hopefully this is better. Perhaps I can be forgiven in that I was rushed to put something together to make the photos available prior to a municipal meeting, and that my pen was directed primarily by my love for this special place and my recognition and frustration that it will ultimately be lost to development and inattention. -=Steve Tessler, PhD*

Credit is extended to Google Maps and Google Earth for being useful environmental investigation tools that help identify issues otherwise unseen from any road.

excluding the google images, all photos © 2008 Steve Tessler. All Rights Reserved

click on a picture to see it bigger and get navigation controls

0_GoogleMap_Hotland area - Threats

0_GoogleMap_Hotland area - pulte-wide-shot-satellite_tilt3D

0_GoogleMap_Hotland area with cemetary construction site

2003-09-06_Hotland - Substrate siltation affects riffle fauna - DSCN3363

2005-08-06_Hotland - Bank erosion after rain event - DSEN2804

2005-08-07_Hotland - Dead crayfish after rain event - DSEN3153

2005-08-07_Hotland - Dead crayfish after rain event - DSEN3156

2005-08-07_Hotland - Dead frog after rain event - DSEN3167

2005-08-07_Hotland - Dead frog after rain event - DSEN3172

2005-10-09_Hotland - Bank erosion and treefall after rain event - DSEN6041

2005-10-09_Hotland - Bank erosion and treefall after rain event - DSEN6042

2005-10-09_Hotland - Bank overflow after rain event - DSEN6184

2005-10-09_Hotland - Silted lower mainstem persists after rain event - DSEN6254

2005-10-09_Hotland - Silted lower mainstem persists after rain event - DSEN6313_bs

2005-10-25_Hotland - Milky Silt in lower mainstem after rain event - DSEN6860

2005-10-25_Hotland - Milky Silt in lower mainstem after rain event - DSEN6862

2006-07-02_Hotland - Dead salamander after rain event - DSFN3007

2006-07-02_Hotland - Dead salamander after rain event - DSFN3010_cb

2006-08-19_Hotland - Silted substrate reduces riffle fauna - DSFN3892

2006-09-02_Hotland - Silt in lower mainstem - DSFN4796

2006-09-02_Hotland - Silt in lower mainstem - DSFN4797

2006-09-02_Hotland - Silt in lower mainstem - DSFN4799

2007-04-15_Hotland - Clean 1st Leftside trib upstream from condos - DSGN0232

2007-04-15_Hotland - Clean 2nd Leftside trib - 20070415174429(1)

2007-04-15_Hotland - Clean trib from condos meets mainstem - DSGN0214

2007-04-15_Hotland - Silt extent (opaque) in mainstem - DSGN0215

2007-04-15_Hotland - Upstream from condos - DSGN0229

2007-10-27_Hotland-P1 - Upstream view from property line - DSGN5302

2007-10-27_Hotland-P2 - Silt extent (opaque) and volume from upstream of Leftside trib above condos - DSGN5288

2007-10-27_Hotland-P3 - Lower mainstem fully involved with siltation - DSGN5282

2007-10-27_Hotland-P4 - Silt discharge from Hotland Run into Crum Creek -DSGN5307

2007-10-27_Hotland-P5 - Silt plume from Hotland Run continues dowstream to bypass bridge - DSGN5310

2007-10-28_Hotland-P6 - NEXT DAY clear discharge from Hotland Run - DSGN5494

2007-10-28_Hotland-P7 - NEXT DAY clear discharge from Hotland Run - DSGN5496

2008-02-01_Hotland_rain-event-heavy-silt-but-not-condo_DSGN7336

2008-03-08_Hotland_1st1-post-nitetime flood mostly clear water_DSGN7822

2008-03-08_Hotland_1st2-post-nitetime flood mostly clear water_DSGN7822

2008-03-08_Hotland_1st3-post-nitetime flood bank fall_DSGN7756

2008-03-08_Hotland_2nd1-pulse-afternoon_ flood silt_DSGN7857

2008-03-08_Hotland_2nd2-pulse-afternoon_ flood silt_DSGN7855

2008-03-08_Hotland_2nd3-pulse-afternoon_ flood silt_DSGN7844

2008-03-08_Hotland_2nd4-pulse-afternoon_ flood silt_DSGN7850

2008-03-08_Hotland_dead-frog-after-storm-DSGN7757_b

*** These pictures are copyrighted and posted for web viewing only.    Any other use requires written permission.   
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© 2008 Steven Tessler   All Rights Reserved

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