Are you worried about your well running dry this summer? Are you wondering if your public water supply is going to implement use restrictions in coming months? If we do suddenly enter a wet spell again, are you concerned about losing valuable rainfall to flooding? A sensible person should be curious about these issues, but here in the Lower Susquehanna River Watershed, we tend to take for granted the water we use on a daily basis.
This Wednesday, June 7, you can learn more about the numerous measures we can take, both individually and as a community, to recharge our aquifers while at the same time improving water quality and wildlife habitat in and around our streams and rivers. From 5:30 to 8:00 P.M., the Chiques Creek Watershed Alliance will be hosting its annual Watershed Expo at the Manheim Farm Show grounds adjacent to the Manheim Central High School in Lancaster County. According to the organization’s web page, more than twenty organizations will be there with displays featuring conservation, aquatic wildlife, stream restoration, Honey Bees, and much more. There will be games and custom-made fish-print t-shirts for the youngsters, plus music to relax by for those a little older. Look for rain barrel painting and a rain barrel giveaway. And you’ll like this—admission and ice cream are free. Vendors including food trucks will be onsite preparing fare for sale.
And there’s much more.
To help recharge groundwater supplies, you can learn how to infiltrate stormwater from your downspouts, parking area, or driveway…
Does your local stream flood every time there’s a downpour, then sometimes dry up during the heat of summer? Has this problem gotten worse over the years? If so, you may be in big trouble during a drought. Loss of base flow in a stream or river is a sure sign of depleted groundwater levels in at least a portion of its drainage basin. Landowners, both public and private, in such a watershed need to start infiltrating stormwater into the ground instead of allowing it to become surface runoff.You can direct the stormwater from your downspout, parking area, or driveway into a rain garden to help recharge the aquifer that supplies your private or public well and nearby natural springs. Displays including this model provided by Rapho Township show you how.
…there will be a tour of a comprehensive stream and floodplain rehabilitation project in Manheim Memorial Park adjacent to the fair grounds…
Have you seen banks like these on your local stream? On waterways throughout the Lower Susquehanna River Watershed, mill dams have trapped accumulations of sediments that eroded from farm fields prior to the implementation of soil conservation practices. These legacy sediments channelize creeks and disconnect them from their now buried floodplains. During storms, water that would have been absorbed by the floodplain is now displaced into areas of higher ground not historically inundated by a similar event.Adjacent to the Manheim Farm Show grounds, the Chiques Creek Stream Restoration Project in Manheim Memorial Park has reconnected the waterway to its historic floodplain by removing a dam and the legacy sediments that accumulated behind it.Chiques Creek in Manheim following removal of hundreds of truck loads of legacy sediments. High water can again be absorbed by the wetlands and riparian forest of the floodplain surrounding this segment of stream. There are no incised banks creating an unnatural channel or crumbling away to pollute downstream waters with nutrients and sediment. Projects similar to this are critical to improving water quality in both the Susquehanna River and Chesapeake Bay. Closer to home, they can help municipalities meet their stormwater management (MS4) requirements.Mark Metzler of Rettew Associates guides a tour of the Chiques Creek rehabilitation. Here, cross vanes, stone structures that provide grade control along the stream’s course, were installed to gently steer the center of the channel away from existing structures. Cross vanes manipulate the velocity of the creek’s flow across its breadth to dissipate potentially erosive energy and more precisely direct the deposition of gravel and sediment.
…and a highlight of the evening will be using an electrofishing apparatus to collect a sample of the fish now populating the rehabilitated segment of stream…
Matt Kofroth, Lancaster County Conservation District Watershed Specialist, operates a backpack electrofishing apparatus while the netting crew prepares to capture the temporarily stunned specimens. The catch is then brought to shore for identification and counting.
…so don’t miss it. We can hardly wait to see you there!
County Conservation District Tree Sales are underway throughout the Lower Susquehanna River Watershed. Now is the time to order for pickup in April. The prices are a bargain and the selection is fabulous. For species descriptions and more details, visit each tree sale web page (click the sale name highlighted in blue). And don’t forget to order bundles of evergreens for planting in mixed clumps and groves to provide winter shelter and summertime nesting sites for our local birds. They’re only $12.00 for a bundle of 10—can’t beat that deal!
Pickup on: Thursday, April 20, 2023 or Friday, April 21, 2023
Don’t mow it. Plant a meadow or pollinator garden instead.Both Cumberland and Perry Counties are offering a native warm-season grass and wildflower seed mix for planting your own meadow or pollinator garden. Perry County is also taking orders for a seed mix specifically formulated to grow plants for attracting hummingbirds and butterflies.
Pickup on: Thursday, April 20, 2023 or Friday, April 21, 2023
The Eastern Hemlock, Pennsylvania’s official state tree, is an excellent choice for addition to your landscape or reforestation project. It tolerates rocky soils and its cones are an prime source of food for birds ranging from chickadees to finches.
The handsome yet underused Northern Red Oak is a sturdy long-lived native tree that is ideal for street-side, lawn, and reforestation plantings. In spring, it can be a magnet for migrating Neotropical birds when its flowers attract a wide variety of tiny insects to its upper reaches. Unlike many other oaks, this species is a relatively fast grower.
In autumn, even after the bright red foliage is gone, the berries of mature Black Gum (Nyssa sylvatica) trees attract a wide variety of birds like this Pileated Woodpecker. The Lebanon County Conservation District is offering Black Gum, also known as Black Tupelo, during their 2023 tree sale. Why not order and plant a half dozen or more?
The Perry County Conservation District is not only offering plants during this year’s sale, you can also purchase bluebird nest boxes for just $12.00 each!For less than the cost of one year of mowing, this stream corridor in Conewago Township, Dauphin County was reforested by the owner with hundreds of native trees, the majority purchased through County Conservation District Tree Sale events spanning a period of several years. By replacing bare soil and mowed areas, the riparian buffer created by these plantings has significantly reduced the nutrient and sediment loads that were polluting the small stream therein known as Brill’s Run. With determination and not a lot of money, you can do it too.But don’t forget the Eastern White Pines!
This stream restoration project is currently underway along a one-mile-long segment of Lancaster Conservancy lands along Conewago Creek. The mountain of dirt is one of several stockpiles of legacy sediments removed to reestablish the floodplain’s historic geomorphology. After eroding from cropland during the years prior to soil conservation, legacy sediments accumulated behind mill dams on waterways throughout the lower Susquehanna watershed. After removal of the dams, creeks were left trapped within the sediment-choked bottomlands, incising steep muddy banks as they cut a new path through the former mill ponds. Excavating legacy sediments from these sites eliminates creek banks and allows floodwaters to again spill directly into wetlands along the stream course. With floodplain and wetland functions restored, nutrients are sequestered, high water is infiltrated to recharge aquifers, sediment loads from collapsing banks are eliminated, and much-needed habitat is created for native plants and animals.
To learn more about this project and others, you’ll want to check out the Landstudies website.
At this very moment, your editor is comfortably numb and is, if everything is going according to plans, again having a snake run through the plumbing in his body’s most important muscle. It thus occurs to him how strange it is that with muscles as run down and faulty as his, people at one time asked him to come speak about and display his marvelous mussels. And some, believe it or not, actually took interest in such a thing. If the reader finds this odd, he or she would not be alone. But the peculiarities don’t stop there. The reader may find further bewilderment after being informed that the editor’s mussels are now in the collection of a regional museum where they are preserved for study by qualified persons with scientific proclivities. All of this show and tell was for just one purpose—to raise appreciation and sentiment for our mussels, so that they might be protected.
Click on the “Freshwater Mussels and Clams” tab at the top of this page to see the editor’s mussels, and many others as well. Then maybe you too will want to flex your muscles for our mussels. They really do need, and deserve, our help.
The Pennsylvania Department of Environmental Protection has issued a “drought watch” for much of the state’s Susquehanna basin including Dauphin, Lebanon, and Perry Counties—plus those counties to their north. Residents are asked to conserve water in the affected areas.
Water conservation measures are voluntary during a drought watch, and most consumers try to cut back on nonessential use. For many though, threats to water supply and water quality generate little concern. This evening, on this farm along a Dauphin County waterway undergoing restoration, we shouldn’t be too surprised to see lots of water being pumped from the creek to soak down liquid manure that was spread on the fields earlier in the week. This happens to be the only property along a five-mile segment of stream that still allows cattle and draft horses to wade, defecate, and urinate in the water. It is the only parcel for nearly seven miles that has eroding banks of legacy sediments that are maintained denuded of nearly all vegetation. Despite some beneficial practices like the use of cover crops, it’s a polluter. And now its operator appears to be engaged in something new: “stream dewatering”. With three irrigation guns in operation, this farmer was easily pumping and removing up to one half or more of the creek’s flow, which at the time, according to a United States Geological Survey gauge less than a mile upstream, was only about 3 cubic feet per second or 1,100 gallons per minute (G.P.M.). That doesn’t let much for the municipalities downstream that rely upon this waterway as a supplemental source of drinking water, does it? Such a large reduction in base flow can threaten the survival of fish and other aquatic inhabitants in the creek, particular during hot summer weather when dissolved oxygen levels can be at their lowest of the year. Water is like a lot of other necessities, no one really gives it a second thought until they don’t have it; and as long as I have mine, that’s all that really matters.
With the gasoline and gunpowder gang’s biggest holiday of the year now upon us, wouldn’t it be nice to get away from the noise and the enduring adolescence for just a little while to see something spectacular that isn’t exploding or on fire? Well, here’s a suggestion: head for the hills to check out the flowers of our native rhododendron, the Great Rhododendron (Rhododendronmaximum), also known as Rosebay.
The Great Rhododendron is an evergreen shrub found growing in the forest understory on slopes with consistently moist (mesic) soils. The large, thick leaves make it easy to identify. During really cold weather, they may droop and curl, but they still remain green and attached to the plant.
Thickets composed of our native heathers/heaths (Ericaceae) including Great Rhododendron, Mountain Laurel, and Pinxter Flower (Rhododendron periclymenoides), particularly when growing in association with Eastern Hemlock and/or Eastern White Pine, provide critical winter shelter for forest wildlife. The flowers of native heathers/heaths attract bees and other pollinating insects and those of the deciduous Pinxter Flower, which blooms in May, are a favorite of butterflies and Ruby-throated Hummingbirds.
A close relative of the Great Rhododendron is the Pinxter Flower, also known as the Pink Azalea.
Forests with understories that include Great Rhododendrons do not respond well to logging. Although many Great Rhododendrons regenerate after cutting, the loss of consistent moisture levels in the soil due to the absence of a forest canopy during the sunny summertime can, over time, decimate an entire population of plants. In addition, few rhododendrons are produced by seed, even under optimal conditions. Great Rhododendron seeds and seedlings are very sensitive to the physical composition of forest substrate and its moisture content during both germination and growth. A lack of humus, the damp organic matter in soil, nullifies the chances of successful recolonization of a rhododendron understory by seed. In locations where moisture levels are adequate for their survival and regeneration after logging, impenetrable Great Rhododendron thickets will sometimes come to dominate a site. These monocultures can, at least in the short term, cause problems for foresters by interrupting the cycle of succession and excluding the reestablishment of native trees. In the case of forests harboring stands of Great Rhododendron, it can take a long time for a balanced ecological state to return following a disturbance as significant as logging.
Ruffed Grouse (Bonasa umbellus) may be particularly sensitive to the loss of winter shelter and travel lanes provided by thickets of Great Rhododendron and other members of the heather/heath family. (Vintage 35 mm image)
In the lower Susquehanna region, the Great Rhododendron blooms from late June through the middle of July, much later than the ornamental rhododendrons and azaleas found in our gardens. Set against a backdrop of deep green foliage, the enormous clusters of white flowers are hard to miss.
Great Rhododendrons sport an attractive blossom cluster. The colors of the flower, especially the markings found only on the uppermost petal, guide pollinators to the stamens (male organs) and pistil (female organ).To this Bumble Bee (Bombus species), the yellowish spots on the uppermost petal of the Great Rhododendron may appear to be clumps of pollen and are thus an irresistible lure.
In the Lower Susquehanna River Watershed, there are but a few remaining stands of Great Rhododendron. One of the most extensive populations is in the Ridge and Valley Province on the north side of Second Mountain along Swatara Creek near Ravine (just off Interstate 81) in Schuylkill County, Pennsylvania. Smaller groves are found in the Piedmont Province in the resort town of Mount Gretna in Lebanon County and in stream ravines along the lower river gorge at the Lancaster Conservancy’s Ferncliff and Wissler’s Run Preserves. Go have a look. You’ll be glad you did.
Great Rhododendron along Route 125 along the base of the north slope of Second Mountain north of Ravine, Schuylkill County, Pennsylvania.Great Rhododendrons beginning to bloom during the second week of July along Swatara Creek north of Ravine, Schuylkill County, Pennsylvania. Note how acid mine drainage continues to stain the rocks (and pollute the water) in the upper reaches of this tributary of the lower Susquehanna.
Fifty years ago this week, the remnants of Hurricane Agnes drifted north through the Susquehanna River basin as a tropical storm and saturated the entire watershed with wave after wave of torrential rains. The storm caused catastrophic flooding along the river’s main stem and along many major tributaries. The nuclear power station at Three Mile Island, then under construction, received its first major flood. Here are some photos taken during the climax of that flood on June 24, 1972. The river stage as measured just upstream of Three Mile Island at the Harrisburg gauge crested at 33.27 feet, more than 10 feet above flood stage and almost 30 feet higher than the stage at present. At Three Mile Island and Conewago Falls, the river was receiving additional flow from the raging Swatara Creek, which drains much of the anthracite coal region of eastern Schuylkill County—where rainfall from Agnes may have been the heaviest.
1972- From the river’s east shore at the mouth of Conewago Creek, Three Mile Island’s “south bridge” crosses the Susquehanna along the upstream edge of Conewago Falls. The flood crested just after covering the roadway on the span. Floating debris including trees, sections of buildings, steel drums, and rubbish began accumulating against the railings on the bridge’s upstream side, leading observers to speculate that the span would fail. When a very large fuel tank, thousands of gallons in capacity, was seen approaching, many thought it would be the straw that would break the camel’s back. It wasn’t, but the crashing sounds it made as it struck the bridge then turned and began rolling against the rails was unforgettable. (Larry L. Coble, Sr. image)1972- In this close-up of the preceding photo, the aforementioned piles of junk can be seen along the upstream side of the bridge (behind the sign on the right). The fuel tank struck and was rolling on the far side of this pile. (Larry L. Coble, Sr. image)2022- Three Mile Island’s “south bridge” as it appeared this morning, June 24,2022.1972- The railroad along the east shore at Three Mile Island’s “south bridge” was inundated by rising water. This flooded automobile was one of many found in the vicinity. Some of these vehicles were overtaken by rising water while parked, others were stranded while being driven, and still others floated in from points unknown. (Larry L. Coble, Sr. image)2022- A modern view of the same location.1972- At the north end of Three Mile Island, construction on Unit 1 was halted. The completed cooling towers can be seen to the right and the round reactor building can be seen behind the generator building to the left. The railroad grade along the river’s eastern shore opposite the north end of the island was elevated enough for this train to stop and shelter there for the duration of the flood. (Larry L. Coble, Sr. image)2022- Three Mile Island Unit 1 as it appears today: shut down, defueled, and in the process of deconstruction.1972- In March of 1979, the world would come to know of Three Mile Island Unit 2. During Agnes in June of 1972, flood waters surrounding the plant resulted in a delay of its construction. In the foreground, note the boxcar from the now defunct Penn Central Railroad. (Larry L. Coble, Sr. image)2022- A current look at T.M.I. Unit 2, shut down since the accident and partial meltdown in 1979.
Pictures capture just a portion of the experience of witnessing a massive flood. Sometimes the sounds and smells of the muddy torrents tell us more than photographs can show.
Aside from the booming noise of the fuel tank banging along the rails of the south bridge, there was the persistent roar of floodwaters, at the rate of hundreds of thousands of cubic feet per second, tumbling through Conewago Falls on the downstream side of the island. The sound of the rapids during a flood can at times carry for more than two miles. It’s a sound that has accompanied the thousands of floods that have shaped the falls and its unique diabase “pothole rocks” using abrasives that are suspended in silty waters after being eroded from rock formations in the hundreds of square miles of drainage basin upstream. This natural process, the weathering of rock and the deposition of the material closer to the coast, has been the prevailing geologic cycle in what we now call the Lower Susquehanna River Watershed since the end of the Triassic Period, more than two hundred million years ago.
More than the sights and sounds, it was the smell of the Agnes flood that warned witnesses of the dangers of the non-natural, man-made contamination—the pollution—in the waters then flowing down the Susquehanna.
Because they float, gasoline and other fuels leaked from flooded vehicles, storage tanks, and containers were most apparent. The odor of their vapors was widespread along not only along the main stem of the river, but along most of the tributaries that at any point along their course passed through human habitations.
Blended with the strong smell of petroleum was the stink of untreated excrement. Flooded treatment plants, collection systems overwhelmed by stormwater, and inundated septic systems all discharged raw sewage into the river and many of its tributaries. This untreated wastewater, combined with ammoniated manure and other farm runoff, gave a damaging nutrient shock to the river and Chesapeake Bay.
Adding to the repugnant aroma of the flood was a mix of chemicals, some percolated from storage sites along watercourses, and yet others leaking from steel drums seen floating in the river. During the decades following World War II, stacks and stacks of drums, some empty, some containing material that is very dangerous, were routinely stored in floodplains at businesses and industrial sites throughout the Susquehanna basin. Many were lifted up and washed away during the record-breaking Agnes flood. Still others were “allowed” to be carried away by the malicious pigs who see a flooding stream as an opportunity to “get rid of stuff”. Few of these drums were ever recovered, and hundreds were stranded along the shoreline and in the woods and wetlands of the floodplain below Conewago Falls. There, they rusted away during the next three decades, some leaking their contents into the surrounding soils and waters. Today, there is little visible trace of any.
During the summer of ’72, the waters surrounding Three Mile Island were probably viler and more polluted than at any other time during the existence of the nuclear generating station there. And little, if any of that pollution originated at the facility itself.
The Susquehanna’s floodplain and water quality issues that had been stashed in the corner, hidden out back, and swept under the rug for years were flushed out by Agnes, and she left them stuck in the stinking mud.
Some of of you may have been wondering why there has been no new content for a while. Well, rest assured that your editor has been replumbed and rewired by some of the best in the business during his recent stay at the Milton S. Hershey Medical Center and he is getting a little stronger every day. More field trips will be on the way soon!
In the meantime, have a look at some of the wide variety of dragonflies gathered along the shoreline at Gifford Pinchot State Park in York County, Pennsylvania. The lake was drained during the winter to perform some maintenance projects and has yet to refill because of the dry spring and early summer we’ve been experiencing. These photos show species seen mostly in the vegetated shallows near the dam.
An ever-on-the-wing Common Green Darner.A Unicorn Clubtail (Arigomphus villosipes).A Black-shouldered Spinyleg (Dromogomphus spinosus).A male Slaty Skimmer (Libellula incesta).A male Slaty Skimmer.A female Slaty Skimmer.A female Swamp Darner (Epiaeschna heros) ovipositing.Very common damselflies, Familiar Bluets (Enallagma civile), a breeding male (right) and female (left) in wheel position.Another common damselfly, a male Powdered Dancer (Argia moesta).Breeding Great Blue Skimmers (Libellula vibrans) in wheel position.Lancet Clubtails (Phanogomphus exilis), a male (above) and a female (below) in wheel position.Black Saddlebags, a male (right) clasping a female (left).
There are lots of others there too. Do have a look.
It’s that time of year when one may expect to find migratory Neotropical songbirds feeding among the foliage of trees and shrubs in the forests, woodlots, and thickets of the lower Susquehanna valley.
During a late afternoon stroll through a headwaters forest east of Conewago Falls outside Mount Gretna, I was pleased to finally come upon a noisy gathering of about two dozen birds. It had, previous to that, been a quiet two hours of walking, only the rumble of an approaching thunderstorm punctuated the silence. Among this little flock were some chickadees, robins, Gray Catbirds, an Eastern Towhee (Pipilo erythrophthalmus), and a Hairy Woodpecker (Dryobates villosus). Besides the catbirds, there were two other species of Neotropical migrants; both were warblers. No less than six Black-throated Blue Warblers (Setophaga caerulescens) were vying for positions in the trees from which they could investigate the stranger on the footpath below. And among the understory shrubs there were at least as many Ovenbirds (Seiurus aurocapilla) satisfying a similar curiosity.
The Black-throated Blue Warbler nests to the north of the lower Susquehanna valley, which it transits as a common spring and fall migrant. On their wintering grounds, they have a thing for warm weather and the better part of a P.B. & J. sandwich.Throughout the Susquehanna watershed, the Ovenbird is a common ground-nesting species in deciduous forests with moderately vegetated understories. The birds seen today may have been a family group that has not yet begun the journey south.
When they depart the Susquehanna valley, these two warbler species will be southbound for wintering ranges that include Florida, many of the Caribbean Islands, Central America, and, for the Ovenbirds, northern South America. Their flights occur at night. During the breeding season and while migrating, both feed primarily on insects and other arthropods . On the wintering grounds, they will consume some fruit. It is during their time in the tropics that the Black-throated Blue Warbler sometimes visits feeding stations that offer grape jelly, much to the delight of bird enthusiasts.
Black-throated Blue Warblers and Ovenbirds commonly winter on the Florida peninsula and in the Bahamas. With the major tropical cyclone Hurricane Dorian presently ripping through the region, these birds are better off taking their time getting there. There’s no need to hurry. The longer they and the other Neotropical migrants hang around, the more we get to enjoy them anyway. So get out there to see them before they go—and remember to look up.
Category 4 Hurricane Dorian at 9:06 EDT on September 2, 2019. If you’re headed that direction, there’s no need to hurry. Note the cloud-free skies over much of the mainland. (NOAA National Environmental Satellite, Data, and Information Service image)A massive bird migration is indicated on Doppler radar in the clear skies over the eastern United States tonight (blue and green over most of the mainland). In this loop of composite radar images from the southeastern states, note the relative absence of a flight over the Florida peninsula where the outer precipitation bands of Hurricane Dorian can be seen. Note too that there appears to be a heavy concentration of birds flying in a southwest direction to cross the Gulf of Mexico, thus continuing their journey to Central or South America while avoiding the deadly hurricane and a much smaller tropical disturbance off the shores of Texas and Tamaulipas, Mexico. (NOAA/National Weather Service image)
Second Mountain Hawk Watch is located on a ridge top along the northern edge of the Fort Indiantown Gap Military Reservation and the southern edge of State Game Lands 211 in Lebanon County, Pennsylvania. The valley on the north side of the ridge, also known as St. Anthony’s Wilderness, is drained to the Susquehanna by Stony Creek. The valley to the south is drained toward the river by Indiantown Run, a tributary of Swatara Creek.
The hawk watch is able to operate at this prime location for observing the autumn migration of birds, butterflies, dragonflies, and bats through the courtesy of the Pennsylvania Game Commission and the Garrison Commander at Fort Indiantown Gap. The Second Mountain Hawk Watch Association is a non-profit organization that staffs the count site daily throughout the season and reports data to the North American Hawk Watch Association (posted daily at hawkcount.org).
Today, Second Mountain Hawk Watch was populated by observers who enjoyed today’s break in the rainy weather with a visit to the lookout to see what birds might be on the move. All were anxiously awaiting a big flight of Broad-winged Hawks, a forest-dwelling Neotropical species that often travels back to its wintering grounds in groups exceeding one hundred birds. Each autumn, many inland hawk watches in the northeast experience at least one day in mid-September with a Broad-winged Hawk count exceeding 1,000 birds. They are an early-season migrant and today’s southeast winds ahead of the remnants of Hurricane Florence (currently in the Carolinas) could push southwest-heading “Broad-wings” out of the Piedmont Province and into the Ridge and Valley Province for a pass by the Second Mountain lookout.
The flight turned out to be steady through the day with over three hundred Broad-winged Hawks sighted. The largest group consisted of several dozen birds. We would hope there are probably many more yet to come after the Florence rains pass through the northeast and out to sea by mid-week. Also seen today were Bald Eagles, Ospreys, American Kestrels, and a migrating Red-headed Woodpecker.
Migrating Broad-winged Hawks circle on a thermal updraft above Second Mountain Hawk Watch to gain altitude before gliding away to the southwest.
Migrating insects included Monarch butterflies, and the three commonest species of migratory dragonflies: Wandering Glider, Black Saddlebags, and Common Green Darner. The Common Green Darners swarmed the lookout by the dozens late in the afternoon and attracted a couple of American Kestrels, which had apparently set down from a day of migration. American Kestrels and Broad-winged Hawks feed upon dragonflies and often migrate in tandem with them for at least a portion of their journey.
Still later, as the last of the Broad-winged Hawks descended from great heights and began passing by just above the trees looking for a place to settle down, a most unwelcome visitor arrived at the lookout. It glided in from the St. Anthony’s Wilderness side of the ridge on showy crimson-red wings, then became nearly indiscernible from gray tree bark when it landed on a limb. It was the dreaded and potentially invasive Spotted Lanternfly (Lycorma delicatula). This large leafhopper is native to Asia and was first discovered in North America in the Oley Valley of eastern Berks County, Pennsylvania in 2014. The larval stage is exceptionally damaging to cultivated grape and orchard crops. It poses a threat to forest trees as well. Despite efforts to contain the species through quarantine and other methods, it’s obviously spreading quickly. Here on the Second Mountain lookout, we know that wind has a huge influence on the movement of birds and insects. The east and southeast winds we’ve experienced for nearly a week may be carrying Spotted Lanternflies well out of their most recent range and into the forests of the Ridge and Valley Province. We do know for certain that the Spotted Lanternfly has found its way into the Lower Susquehanna River Watershed.
This adult Spotted Lanternfly landed in a birch tree behind the observers at the Second Mountain Hawk Watch late this afternoon. It was first recognized by its bright red wings as it glided from treetops on the north side of the lookout.
It was a routine occurrence in many communities along tributaries of the lower Susquehanna River during the most recent two months. The rain falls like it’s never going to stop—inches an hour. Soon there is flash flooding along creeks and streams. Roads are quickly inundated. Inevitably, there are motorists caught in the rising waters and emergency crews are summoned to retrieve the victims. When the action settles, sets of saw horses are brought to the scene to barricade the road until waters recede. At certain flood-prone locations, these events are repeated time and again. The police, fire, and Emergency Medical Services crews seem to visit them during every torrential storm—rain, rescue, rinse, and repeat.
We treat our local streams and creeks like open sewers. Think about it. We don’t want rainwater accumulating on our properties. We pipe it away and grade the field, lawn, and pavement to roll it into the neighbor’s lot or into the street—or directly into the waterway. It drops upon us as pure water and we instantly pollute it. It’s a method of diluting all the junk we’ve spread out in its path since the last time it rained. A thunderstorm is the big flush. We don’t seem too concerned about the litter, fertilizer, pesticides, motor fluids, and other consumer waste it takes along with it. Out of sight, out of mind.
Failure to retain and infiltrate stormwater to recharge aquifers can later result in well failures and reduced base flow in streams. (Conoy Creek’s dry streambed in June, 2007)
Perhaps our lack of respect for streams and creeks is the source of our complete ignorance of the function of floodplains.
Floodplains are formed over time as hydraulic forces erode bedrock and soils surrounding a stream to create adequate space to pass flood waters. As floodplains mature they become large enough to reduce flood water velocity and erosion energy. They then function to retain, infiltrate, and evaporate the surplus water from flood events. Microorganisms, plants, and other life forms found in floodplain wetlands, forests, and grasslands purify the water and break down naturally-occurring organic matter. Floodplains are the shock-absorber between us and our waterways. And they’re our largest water treatment facilities.
Why is it then, that whenever a floodplain floods, we seem motivated to do something to fix this error of nature? Man can’t help himself. He has a compulsion to fill the floodplain with any contrivance he can come up with. We dump, pile, fill, pave, pour, form, and build, then build some more. At some point, someone notices a stream in the midst of our new creation. Now it’s polluted and whenever it storms, the darn thing floods into our stuff—worse than ever before. So the project is crowned by another round of dumping, forming, pouring, and building to channelize the stream. Done! Now let’s move all our stuff into our new habitable space.
Natural Floodplain- Over a period of hundreds or thousands of years, the stream (dark blue) has established a natural floodplain including wetlands and forest. In this example, buildings and infrastructure are located outside the zone inundated by high water (light blue) allowing the floodplain to function as an effective water-absorbing buffer.Impaired Floodplain- Here the natural floodplain has been filled for building (left) and paved for recreation area parking (right). The stream has been channelized. Flood water (light blue) displaced by these alterations is likely to inundate areas not previously impacted by similar events. Additionally, the interference with natural flow will create new erosion points that could seriously damage older infrastructure and properties.
The majority of the towns in the lower Susquehanna valley with streams passing through them have impaired floodplains. In many, the older sections of the town are built on filled floodplain. Some new subdivisions highlight streamside lawns as a sales feature—plenty of room for stockpiling your accoutrements of suburban life. And yes, some new homes are still being built in floodplains.
When high water comes, it drags tons of debris with it. The limbs, leaves, twigs, and trees are broken down by natural processes over time. Nature has mechanisms to quickly cope with these organics. Man’s consumer rubbish is another matter. As the plant material decays, the embedded man-made items, particularly metals, treated lumber, plastics, Styrofoam, and glass, become more evident as an ever-accumulating “garbage soil” in the natural floodplains downstream of these impaired areas. With each storm, some of this mess floats away again to move ever closer to Chesapeake Bay and the Atlantic. Are you following me? That’s our junk from the curb, lawn, highway, or parking lot bobbing around in the world’s oceans.
A shed, mobile home, or house can be inundated or swept away during a flood. Everything inside (household chemicals, gasoline, fuel oil, pesticides, insulation, all those plastics, etc.) instantly pollutes the water. Many communities that rely on the Susquehanna River for drinking water are immediately impacted, including Lancaster, PA and Baltimore, MD. This dumpster was swept away from a parking lot in a floodplain. It rolled in the current, chipping away at the bridge before spilling the rubbish into the muddy water. After the flood receded, the dumpster was found a mile downstream. Its contents are still out there somewhere.Floodplains along the lower Susquehanna River are blanketed with a layer of flotsam that settles in place as high water recedes. These fresh piles can be several feet deep and stretch for miles. Nature decomposes the organic twigs and driftwood to build soil-enriching humus. However, the plastics and other man-made materials that do not readily decay or do not float away toward the sea during the next flood are incorporated into the alluvium and humus creating a “garbage soil”. Over time, the action of abrasives in the soil will grind small particles of plastics from the larger pieces. These tiny plastics can become suspended in the water column each time the river floods. What will be the long-term impact of this type of pollution?Anything can be swept away by the powerful hydraulic forces of flowing water. Large objects like this utility trailer can block passages through bridges and escalate flooding problems.The cost of removing debris often falls upon local government and is shared by taxpayers.Here, a junked boat dock is snagged on the crest of the York Haven Dam at Conewago Falls. Rising water eventually carried it over the dam and into the falls where it broke up. This and tons of other junk are often removed downstream at the Safe Harbor Dam to prevent damage to turbine equipment. During periods of high water, the utility hauls debris by the truck-load to the local waste authority for disposal. For the owners of garbage like this dock, it’s gone and it’s somebody else’s problem now.Motor vehicles found after floating away from parking areas in floodplains can create a dangerous dilemma for police, fire, and E.M.S. personnel, particularly when no one witnesses the event. Was someone driving this car or was it vacant when it was swept downstream? Should crews be put at risk to locate possible victims?
Beginning in 1968, participating municipalities, in exchange for having coverage provided to their qualified residents under the National Flood Insurance Program, were required to adopt and enforce a floodplain management ordinance. The program was intended to reduce flood damage and provide flood assistance funded with premiums paid by potential victims. The program now operates with a debt incurred during severe hurricanes. Occurrences of repetitive damage claims and accusations that the program provides an incentive for rebuilding in floodplains have made the National Flood Insurance Program controversial.
In the Lower Susquehanna River Watershed there are municipalities that still permit new construction in floodplains. Others are quite proactive at eliminating new construction in flood-prone zones, and some are working to have buildings removed that are subjected to repeated flooding.
Another Wall— Here’s an example of greed by the owner, engineer, and municipality… placing their financial interests first. The entire floodplain on the north side of this stream was filled, then the wall was erected to contain the material. A financial institution’s office and parking lot was constructed atop the mound. This project has channelized the stream and completely displaced half of the floodplain to a height of 15 to 20 feet. Constructed less than five years ago, the wall failed already and has just been totally reconstructed. The photo reveals how recent flooding has begun a new erosion regime where energy is focused along the base of the wall. Impairment of a floodplain to this degree can lead to flooding upstream of the site and erosion damage to neighboring infrastructure including roads and bridges.The floodplain along this segment of the lower Swatara Creek in Londonderry Township, Dauphin County is free to flood. Ordinances prohibit new construction here and 14 older houses that repeatedly flooded were purchased, dismantled, and removed using funding from the Federal Emergency Management Agency (F.E.M.A). A riparian buffer was planted and some wetland restorations were incorporated into stormwater management installations along the local highways. When the waters of the Swatara rise, the local municipality closes the roads into the floodplain. Nobody lives or works there anymore, so no one has any reason to enter. There’s no need to rescue stubborn residents who refused advice to evacuate. Sightseers can park and stand on the hill behind the barricades and take all the photographs they like.A new Pennsylvania Turnpike bridge across Swatara Creek features wide passage for the stream below. Water flowing in the floodplain can pass under the bridge without being channelized toward the path where the stream normally flows in the center. The black asterisk-shaped floats spin on the poles to help deflect debris away from the bridge piers. (flood crest on July 26, 2018)People are curious when a waterway floods and they want to see it for themselves. Wouldn’t it be wise to anticipate this demand for access by being ready to accommodate these citizens safely? Isn’t a parking lot, picnic area, or manicured park safer and more usable when overlooking the floodplain as opposed to being located in it? Wouldn’t it be a more prudent long-term investment, both financially and ecologically, to develop these improvements on higher ground outside of flood zones?Now would be a good time to stop the new construction and the rebuilding in floodplains. Aren’t the risks posed to human life, water quality, essential infrastructure, private property, and ecosystems too great to continue?Isn’t it time to put up the white flag and surrender the floodplains to the floods? That’s why they’re there. Floodplains are for flooding.
There are two Conewago Creek systems in the Lower Susquehanna River Watershed. One drains the Gettysburg Basin west of the river, mostly in Adams and York Counties, then flows into the Susquehanna at the base of Conewago Falls. The other drains the Gettysburg Basin east of the river, flowing through Triassic redbeds of the Gettysburg Formation and York Haven Diabase before entering Conewago Falls near the south tip of Three Mile Island. Both Conewago Creeks flow through suburbia, farm, and forest. Both have their capacity to support aquatic life impaired and diminished by nutrient and sediment pollution.
This week, some of the many partners engaged in a long-term collaboration to restore the east shore’s Conewago Creek met to have a look at one of the prime indicators of overall stream habitat health—the fishes. Kristen Kyler of the Lower Susquehanna Initiative organized the effort. Portable backpack-mounted electrofishing units and nets were used by crews to capture, identify, and count the native and non-native fishes at sampling locations which have remained constant since prior to the numerous stream improvement projects which began more than ten years ago. Some of the present-day sample sites were first used following Hurricane Agnes in 1972 by Stambaugh and Denoncourt and pre-date any implementation of sediment and nutrient mitigation practices like cover crops, no-till farming, field terracing, stormwater control, nutrient management, wetland restoration, streambank fencing, renewed forested stream buffers, or modernized wastewater treatment plants. By comparing more recent surveys with this baseline data, it may be possible to discern trends in fish populations resulting not only from conservation practices, but from many other variables which may impact the Conewago Creek Warmwater Stream ecosystem in Dauphin, Lancaster, and Lebanon Counties.
So here they are. Enjoy these shocking fish photos.
Matt Kofroth, Watershed Specialist with the Lancaster County Conservation District, operates the electrofishing wand in Conewago Creek while his team members prepare to net and collect momentarily-stunned fish. Three other electrofishing units operated by staff from the Susquehanna River Basin Commission and aided by teams of netters were in action at other sample locations along the Conewago on this day.Really big fish, such as this Common Carp (Cyprinus carpio), were identified, counted, and immediately returned to the water downstream of the advancing electrofishing team. Koi of the garden pond are a familiar variety of Common Carp, a native of Asia.Other fish, such as the Swallowtail Shiner, Redbreast Sunfish (Lepomis auritus), Fallfish, and suckers seen here, were placed in a sorting tank.Fallfish (Semotilus corporalis) are very active and require plenty of dissolved oxygen in the water to survive. Fallfish, Rainbow Trout (Oncorhynchus mykiss), and Smallmouth Bass (Micropterus dolomieu) were quickly identified and removed from the sorting tank for release back into the stream. Other larger, but less active fish, including suckers, quickly followed.Small fish like minnows were removed from the sorting tank for a closer look in a hand-held viewing tank. This Fathead Minnow (Pimephales promelas) was identified, added to the tally sheet, and released back into the Conewago. The Fathead Minnow is not native to the Susquehanna drainage. It is the minnow most frequently sold as bait by vendors.A breeding condition male Bluntnose Minnow (Pimephales notatus).The Cutlips Minnow (Exoglossum maxillingua) is a resident of clear rocky streams. Of the more than 30 species collected during the day, two native species which are classified as intolerant of persisting stream impairment were found: Cutlips Minnow and Swallowtail Shiner.This young River Chub (Nocomis micropogon) is losing its side stripe. It will be at least twice as large at adulthood.The Eastern Blacknose Dace (Rhinichthys atratulus) is found in clear water over pebble and stone substrate..The Longnose Dace (Rhinichthys cataractae) is another species of pebbly rocky streams.A juvenile Golden Shiner (Notemigonus crysoleucas). Adults lack the side stripe and grow to the size of a sunfish.A Swallowtail Shiner (Notropis procne) and a very young White Sucker (Catostomus commersonii) in the upper left of the tank.A Spotfin Shiner (Cyprinella spiloptera).A breeding male Spotfin Shiner. Show-off!The Margined Madtom (Noturus insignis) is a small native catfish of pebbly streams.The Banded Killifish (Fundulus diaphanus) is adept at feeding upon insects, including mosquitos.A young Rock Bass (Ambloplites rupestris). This species was introduced to the Susquehanna and its tributaries.The Greenside Darter (Etheostoma blennioides) is not native to the Susquehanna basin. The species colonized the Conewago Creek (east) from introduced local populations within the last five years.The Tessellated Darter (Etheostoma olmstedi) is a native inhabitant of the Susquehanna and its tributaries.The stars of the day were the American Eels (Anguilla rostrata).After collection, each eel was measured and weighed using a scale and dry bucket. This specimen checked in at 20 inches and one pound before being released.Prior to the construction of large dams, American Eels were plentiful in the Susquehanna and its tributaries, including the Conewago. They’ve since been rarities for more than half a century. Now they’re getting a lift.American Eels serve as an intermediate host for the microscopic parasitic glochidia (larvae) of the Eastern Elliptio (Elliptio complanata), a declining native freshwater mussel of the Lower Susquehanna River Watershed. While feeding on their host (usually in its gills), the glochidia cause little injury and soon drop off to continue growth, often having assured distribution of their species by accepting the free ride. Freshwater mussels are filter feeders and improve water quality. They grow slowly and can live for decades.American Eels are a catadromous species, starting life as tiny glass eels in the saltwater of the Atlantic Ocean, then migrating to tidal brackish marshes and streams (males) or freshwater streams (females) to mature. This 20-incher probably attempted to ascend the Susquehanna as an elver in 2016 or 2017. After hitching a ride with some friendly folks, she bypassed the three largest dams on the lower Susquehanna (Conowingo, Holtwood, and Safe Harbor) and arrived in the Conewago where she may remain and grow for ten years or more. To spawn, a perilous and terminally fatal journey to the Sargasso Sea awaits her. (You may better know the area of the Sargasso Sea as The Bermuda Triangle…a perilous place to travel indeed!)
SOURCES
Normandeau Associates, Inc. and Gomez and Sullivan. 2018. Muddy Run Pumped Storage Project Conowingo Eel Collection Facility FERC Project 2355. Prepared for Exelon.
Stambaugh, Jr., John W., and Robert P. Denoncourt. 1974. A Preliminary Report on the Conewago Creek Faunal Survey, Lancaster County, Pennsylvania. Proceedings of the Pennsylvania Academy of Sciences. 48: 55-60.
Two days ago, widespread rain fell intermittently through the day and steadily into the night in the Susquehanna drainage basin. The temperature was sixty degrees, climbing out of a three-week-long spell of sub-freezing cold in a dramatic way. Above the ice-covered river, a very localized fog swirled in the southerly breezes.
By yesterday, the rain had ended as light snow and a stiff wind from the northwest brought sub-freezing air back to the region. Though less than an inch of rain fell during this event, much of it drained to waterways from frozen or saturated ground. Streams throughout the watershed are being pushed clear of ice as minor flooding lifts and breaks the solid sheets into floating chunks.
Today, as their high flows recede, the smaller creeks and runs are beginning to freeze once again. On larger streams, ice is still exiting with the cresting flows and entering the rising river.
Ice chunks on Swatara Creek merge into a dense flow of ice on the river in the distance. Swatara Creek is the largest tributary to enter the Susquehanna in the Gettysburg Basin. The risk of an ice jam impounding the Swatara here at its mouth is lessened because rising water on the river has lifted and broken the ice pack to keep it moving without serious impingement by submerged obstacles. Immovable ice jams on the river can easily block the outflow from tributaries, resulting in catastrophic flooding along these streams.Fast-moving flows of jagged ice race toward Three Mile Island and Conewago Falls. The rising water began relieving the compression of ice along the shoreline during the mid-morning. Here on the river just downstream of the mouth of Swatara Creek, ice-free openings allowed near-shore piles to separate and begin floating away after 10:30 A.M. E.S.T. Moving masses of ice created loud rumbles, sounding like a distant thunderstorm.Ice being pushed and heaved over the crest of the York Haven Dam at Conewago Falls due to compression and rising water levels.Enormous chunks of ice being forced up and over the York Haven Dam into Conewago Falls and the Pothole Rocks below.Ice scours Conewago Falls, as it has for thousands of years.The action of ice and suspended abrasives has carved the York Haven Diabase boulders and bedrock of Conewago Falls into the amazing Pothole Rocks.The roaring torrents of ice-choked water will clear some of the woody growth from the Riverine Grasslands of Conewago Falls.To the right of center in this image, a motorcar-sized chunk of ice tumbles over the dam and crashes into the Pothole Rocks. It was one of thousands of similar tree-and-shrub-clearing projectiles to go through the falls today.
The events of today provide a superb snapshot of how Conewago Falls, particularly the Diabase Pothole Rocks, became such a unique place, thousands of years in the making. Ice and flood events of varying intensity, duration, and composition have sculpted these geomorphologic features and contributed to the creation of the specialized plant and animal communities we find there. Their periodic occurrence is essential to maintaining the uncommon habitats in which these communities thrive.
Fish Crows (Corvus ossifragus) gather along the flooding river shoreline. Soon there’ll be plenty of rubbish to pick through, some carrion maybe, or even a displaced aquatic creature or two to snack upon.
