Close to 15,000 acres of underwater grasses have disappeared from the Chesapeake Bay.
While robust grass beds on the Susquehanna Flats and expanding beds in the James River offer two examples of the Bay’s resilience, an aerial survey conducted by the Virginia Institute of Marine Science (VIMS) showed a 21 percent decline in the Bay’s grasses in 2012. This so-called “alarming” loss—from just over 63,000 acres in 2011 to just over 48,000 in 2012—approaches lows last reported in 1986.
In a report released this week, Chesapeake Bay Program scientists attributed last year's decline in grass beds to warmer-than-normal water temperatures seen in 2010 and strong storms seen in the fall of 2011. The former "cooked" grasses in the Lower Bay, while the latter pushed excess sediment into rivers and streams, clouding the water and creating unfavorable growing conditions for aquatic plants in the Upper and Middle Bay.
These strong storms and episodes of heat stress have occurred alongside a widespread decline in water clarity, said Bob Orth, coordinator of the VIMS Submerged Aquatic Vegetation Survey. While Orth remains "concerned" over the decline in bay grasses, he noted that favorable growing conditions in the future could lead to quick signs of recovery in a species that is fast to respond to water quality changes—both good and bad.
"The best thing we can do [for bay grasses] is to improve water quality," said Lee Karrh, a biologist with the Maryland Department of Natural Resources (DNR) and chair of the Bay Program's Submerged Aquatic Vegetation Workgroup. "If you improve water quality and reduce chronic problems, then the Bay should be able to deal with episodic events easier than it has been able to in the past."
Underwater grasses—also known as submerged aquatic vegetation or SAV—are critical to the Bay ecosystem, offering food and habitat to countless critters while absorbing nutrients, trapping sediment and reducing shoreline erosion. The Bay Program uses underwater grass abundance as an indicator of Bay health, and has this week released a data visualization tool that allows users to track changes in grass abundance over time, as dominant species ebb and flow and grass beds shrink and expand.
Read more about the 2012 Distribution of Submerged Aquatic Vegetation in the Chesapeake Bay.
A recent assessment of Superstorm Sandy shows the hurricane did less damage to the Chesapeake Bay than some feared, thanks in large part to its timing and track.
According to a University of Maryland report, the late-October hurricane whose path traveled north of the Bay had “ephemeral” impacts on Bay water quality—especially when compared to past storms.
The summertime arrival of Tropical Storm Agnes in 1972, for instance, coincided with a critical growing period for oysters, crabs and underwater grasses, and had a damaging effect on all three. But because Sandy arrived in the fall, the nutrients and sediment that it sent into the Bay were unable to fuel harmful algae blooms or damage the underwater grasses that had already begun to die back for the season. And while Tropical Storm Lee in 2011 brought heavy rainfall and a large plume of sediment to the Susquehanna River, the bulk of Sandy’s rainfall was concentrated elsewhere, meaning minimal scouring of sediment from behind the Conowingo Dam and “virtually no sediment plume” in the Upper Bay.
These findings echo those released in November by the National Oceanic and Atmospheric Administration (NOAA) and the U.S. Geological Survey (USGS).
Read more about the ecological impacts of Sandy on the Chesapeake Bay.
The superstorm known as Sandy has boosted river flow in the Chesapeake Bay watershed, but favorable winds and timing meant it did not do as much damage as some feared.
Image courtesy thisisbossi/Flickr
According to the National Oceanic and Atmospheric Administration (NOAA), much of the watershed avoided surge-related flooding during the height of the storm, as northerly winds kept a large push of water from moving into the Bay. While some locations did experience post-storm surges of two to four feet, even the highest surge was about half of that seen during Hurricane Isabel in 2003.
Preliminary data from the USGS also show that the accompanying nutrient and sediment loads pushed into rivers from polluted runoff are not expected to approach those seen in 2011 from Hurricane Irene and Tropical Storm Lee. Nor is the flow in the Susquehanna River expected to produce a significant scour of sediment from the Conowingo Reservoir. While nutrients and sediment can disturb the habitat of underwater grasses and marine life, Sandy’s end-of-autumn timing—while underwater grasses are dormant—means that its impact will likely not be as great as that of a super-sized summertime storm.
According to NOAA, much of Sandy’s rainfall is still working its way down the watershed’s rivers. Scientists from NOAA, USGS and other Chesapeake Bay Program partners will continue to conduct in-depth research on Sandy’s effects on the Bay and its resources.
UPDATED: Superstorm Sandy brought rain, wind and flooding to the mid-Atlantic coast. But how has the storm affected the Chesapeake Bay? Take a look at the headlines below for the latest news on the environmental impacts of this damaging storm.
Sandy May Leave Toxic Legacy
Discovery News 11/05/2012
Hurricane Sandy has little effect on Bay
The (Easton, Md.) Star Democrat 11/05/2012
Coastal cities seek protections against superstorms
The Washington Post 11/04/2012
Gushing Susquehanna Called a Bigger Threat to Bay Pollution than Local Runoff
Southern Maryland Online 11/04/2012
Sandy might not harm Bay
The (Annapolis, Md.) Capital 11/04/2012
Sandy Environmental Toll: Polluted Rivers, Lost Seabirds
International Business Times 11/02/2012
Sandy's path, derecho eased wind damage in region
Southern Maryland News 11/02/2012
Raw sewage spills into Mattawoman Creek
Southern Maryland News 11/02/2012
Researchers Gauging Sandy's Impact on Chesapeake
Associated Press 11/01/2012
Beach Repairs After Sandy May Cost $8 Million a Mile
Bloomberg News 11/01/2012
In the wake of Sandy, Tangier makes its case for help
The Richmond (Va.) Times-Dispatch 11/01/2012
Sandy's Impact on Chesapeake Bay Less Than Expected
Patch.com (Edgewater-Davidsonville, Md.) 11/01/2012
Eastern Shore resilient, state will help in recovery, McDonnell says
The Richmond (Va.) Times-Dispatch 10/31/2012
Some Va. waters to be opened to shellfish harvesting
The (Hampton Roads) Virginian-Pilot 10/31/2012
Civil Air Patrol begins coastline damage assessment
The (Easton, Md.) Star Democrat 10/31/2012
Havre de Grace Not Worried About Flooding from Conowingo Dam
Patch.com (Havre de Grace, Md.) 10/31/2012
Power restored to Maryland water treatment plant
WTOP (Washington, D.C.) 103.5 FM 10/31/2012
Storm triggers big Howard sewage spill
B'More Green 10/30/2012
Sewage spilled into waterways from Virginia to New England
United Press International 10/30/2012
After the Storm: Cecil County Recovers but Bay, Susquehanna Still a Worry
The Cecil (Md.) Times 10/30/2012
Virginia portions of the Chesapeake Bay closed to shellfish harvesting due to flooding, rain
Associated Press 10/29/2012
Hurricane Sandy poses environmental threat to Chesapeake Bay
The Washington Post 10/27/2012
October 26, 2012 -- Hurricane Sandy could make landfall along the mid-Atlantic shoreline, raising concern over potential wind, rain, inland and coastal flooding and erosion in the Chesapeake Bay watershed.
Image courtesy National Hurricane Center
At the time of this post, the latest model simulation from the National Hurricane Center shows the storm hitting the mid-Atlantic region early next week.
But an exact forecast is hard to make. According to the National Oceanic and Atmospheric Administration (NOAA), the storm’s large size, unusual pattern as it interacts with an incoming cold-weather storm and timing to coincide with the full moon’s higher-than-normal tides make it difficult to predict its precise path and the resulting consequences it could have for the region.
Under certain conditions, the storm could create problems for the Bay. Excess rainfall in the watershed could increase the flow of polluted stormwater into rivers and streams and lead to inland flooding. A spike in Pennsylvania rainfall could boost the flow of the Susquehanna River and push sediment and debris into the Upper Bay, clouding the water and impairing marine life habitat. Strong winds could lead to strong waves, increasing erosion along beaches and shorelines.
When storms like this one enter the Bay ecosystem, the Chesapeake Bay Program’s network of scientists and experts monitor the storm’s effects on waters, habitats and resources.
While large storms can pose a challenge for the Bay, some regions have shown resilience to severe weather. After Tropical Storm Lee, for instance, scientists noticed that despite a decline in underwater grasses overall, grass beds in the Susquehanna Flats remained intact; widgeon grass beds grew, fueled by an influx of freshwater; and new grass beds were found in the James River.
The National Hurricane Center’s forecast track is updated every three hours. NOAA encourages citizens to check national and local weather forecasts often to prepare for the oncoming storm.
Bay conditions can be monitored at any time through the Chesapeake Bay Interpretive Buoy System.
Learn more about preparing for a storm like Sandy.
During the Atlantic Basin's six-month hurricane season, wetlands along the edges of rivers, streams and Chesapeake Bay shorelines play a critical role in maintaining healthy waters.
Storms and hurricanes like Lee and Irene in 2011 or Isabel in 2003 can have serious consequences for the Bay region, as rains wash nutrients like nitrogen and phosphorous off of farms, lawns and gardens; push sediment-laden runoff into local waterways; and inundate grass and oyster beds with suffocating silt. But this sort of storm damage is often temporary, and can be mitigated by abundant, healthy wetlands and ongoing efforts to restore them.
Wetlands stabilize shorelines, protect properties from strong waves and surging floods, soak up stormwater runoff and absorb sediment and chemical contaminants. While wetlands alone will not stop excess nutrients and sediment from reaching our waters, strong, healthy wetlands are vital to reducing the impacts of polluted runoff and supporting the Bay's resilience.
Last year, Chesapeake Bay Program partners restored more than 3,700 acres of wetlands in the Bay watershed--an acreage equivalent to about 2,855 football fields. These efforts build on the 14,765 acres of wetlands established from 1998 to 2010 and represent a solid step by Bay jurisdictions toward meeting the goal to restore 30,000 acres and rejuvenate 150,000 acres of these landscapes by 2025.
An unusual sequence of weather events, including a wet spring, a hot, dry summer, and two tropical storms, caused the Chesapeake Bay’s health to decline in 2011, according to the University of Maryland Center for Environmental Science (UMCES) and the National Oceanic and Atmospheric Administration (NOAA).
(Image courtesy Chesapeake EcoCheck)
Scientists gave the Bay a D+ on the latest Chesapeake Bay Report Card, an annual assessment of the health of the Bay and its tidal rivers. The score of 38 percent was the second lowest since assessments began in 1986 and down from a C- in 2010.
Only two areas – the lower western shore and the Patapsco and Back rivers – improved last year. The rest of the Bay’s segments remained the same or got worse. Scientists recorded lower scores in the Patuxent River, Rappahannock River, James River, Tangier Sound, and the upper and middle Bay.
"The spring rains and hot, dry summer followed by Tropical Storm Lee and Hurricane Lee led to poor health throughout Chesapeake Bay and its tributaries," said Dr. Bill Dennison of the University of Maryland Center for Environmental Science. "While we have been making considerable progress in various restoration activities, these results indicate we still need to do much more to reduce the input of nutrients and sediments from stormwater runoff into the Bay."
The Bay’s health is largely affected by weather conditions. Rainfall carries pollution from farms, cities and suburbs to storm drains, streams and eventually the Bay. Even as the government, communities and citizens work to reduce pollution, an increase in stormwater runoff can mask the effects of these improvements.
Wet weather last spring washed more nutrient pollution into the water, fueling the growth of algae blooms that blocked sunlight from reaching bay grasses. Hot, dry weather allowed these algae blooms to persist through summer, leading to low-oxygen “dead zones” in the Bay’s bottom waters. In late summer, the Bay was slammed by the effects of Hurricane Irene and Tropical Storm Lee, both of which worsened water clarity.
"The report card clearly indicates that the Chesapeake Bay watershed is a dynamic ecosystem subject to severe weather events," said Bay Program Director Nick DiPasquale. “The silver lining is that the Hopkins-UMCES study of 60 years of water quality data concluded that a decrease in the frequency and severity of dead zones in the Bay is the direct result of implementing measures to reduce nitrogen and phosphorus pollution. We know what works; we just need to do more of it."
The Chesapeake Bay Report Card, produced by the EcoCheck partnership, offers a timely and geographically detailed assessment of the health of the Bay’s water quality and aquatic life. Visit EcoCheck’s website for more information about the report card, including region-specific data and downloadable graphics.
Fewer acres of bay grasses grew in the shallows of the Chesapeake Bay and its tidal rivers in 2011, according to scientists with the Chesapeake Bay Program. Bay grass acreage fell to an estimated 63,074 acres in 2011, down from 79,664 acres in 2010. This is the lowest Bay-wide acreage measured since 2006.
Because of heavy rainstorms that led to cloudy, muddy conditions that blocked monitoring efforts, only 57,956 acres of bay grasses were actually mapped in 2011. However, scientists believe about 5,119 acres of bay grasses may have been present during the height of the growing season, leading to the final estimated Bay-wide figure of 63,074 acres.
Bay grasses – also known as submerged aquatic vegetation or SAV – are a critical part of the Bay ecosystem. These underwater meadows provide fish, crabs and other aquatic life with food and habitat, absorb nutrients, trap sediment, reduce erosion, and add oxygen to the water. Bay grasses are also an excellent measure of the Bay's overall condition because their health is closely linked with the Bay’s health.
“2011 was the year that bucked two trends we’ve seen over the last decade,” said Lee Karrh, chair of the Bay Program’s Submerged Aquatic Vegetation (SAV) Workgroup. “The Upper Bay had major decreases after years of increasing or sustained high acreages. On the other hand, the brackish parts of the Middle Bay witnessed dramatic increases in 2011, after prolonged decreases since the turn of the century.”
Experts agree that extreme weather conditions in 2010 and 2011 led to the substantial decrease in bay grasses. According to Bob Orth, scientist with the Virginia Institute of Marine Science (VIMS) and coordinator of the annual bay grass survey:
In the upper Bay (from the mouth of the Susquehanna River to the Chesapeake Bay Bridge), bay grasses covered approximately 13,287 acres, down from 21,353 acres in 2010. This is most likely an underestimate because scientists did not monitor the area until November, once muddy conditions improved but well past the end of the growing season. One bright spot in the upper Bay was the more than doubling of bay grass acreage in the Chester River and near Eastern Neck.
In the middle Bay (from the Bay Bridge to Pocomoke Sound and the Potomac River), bay grasses decreased 4 percent to an estimated 34,142 acres, down from 35,446 acres in 2010. (Only 29,023 acres were mapped, but scientists estimate that an additional 5,119 acres may have been present.) Large eelgrass losses were observed in Tangier Sound. These were offset by widgeon grass gains in many areas, including Eastern Bay and the Choptank River.
In the lower Bay (south of Pocomoke Sound and the Potomac River), bay grasses covered 15,645 acres, down 32 percent from 22,685 acres in 2010. Hot summer temperatures in 2010 led to this significant drop in acreage, which offset any gains that followed in 2011. Eelgrass in many parts of the lower Bay had been recovering from similar heat-related losses that took place in 2005.
Despite Bay-wide losses, there were a few bits of good news for bay grasses last year. The huge, dense bed on the Susquehanna Flats – which has increased threefold in size over the past 20 years – survived the late summer tropical storms, showing how resilient healthy bay grass beds can be to natural disturbances. Also, scientists recorded the first-ever bay grass bed in the mainstem James River since the area was first surveyed in 1998.
Annual bay grass acreage is estimated through an aerial survey, which is conducted from late spring to early autumn. Residents can do their part to help restore bay grasses by not fertilizing in the spring and planting more plants to reduce polluted runoff from backyards.
For detailed information about 2011 bay grasses acreage, including aerial photos and year-to-year comparisons, visit VIMS' SAV blog. For more information about the aerial survey and bay grass monitoring efforts, visit VIMS’ SAV website.
If last week’s sixty-degree days weren’t enough to convince you that winter has bid us farewell and spring is just around the corner, these harbingers of the changing seasons surely will! Take a look around your backyard, community or local park for these five telltale signs of spring in the Chesapeake Bay region.
(Image courtesy bbodjack/Flickr)
If you happen to live near a pond or wetland, you may be accustomed to hearing a chorus of “peeps” in early spring. The northern spring peeper is one of the first to breed in spring. This small amphibian’s mating call is described as a “peep,” but it can be almost deafening when hundreds of frogs sing in one location.
(Image courtesy bobtravis/Flickr)
These yellow beauties are the first bulb plants to pop up each March, sometimes emerging through melting snow and always signaling warmer weather ahead. Any gardener will tell you there’s no way to tell exactly when daffodils will bloom, but they seem to pop up almost overnight. A website tracks photos and reports of the first daffodil sightings each year around the world.
If you can’t get enough of these buttercup blooms, head over to the American Daffodil Society’s National Convention in April in Baltimore.
(Image courtesy Martin LaBar/Flickr)
Where there are flowers, bees should follow – but native bee populations have fallen rapidly in recent years. Find out how you can make your yard a bee haven and help give bees a home! (Don’t worry – most of the Chesapeake Bay watershed’s native bees don’t sting!)
A bee-friendly backyard will benefit you and your garden: bees pollinate plants and crops, a service that’s worth millions each year to our economy.
“PEENT! PEENT!” The mating call of the American woodcock may be a familiar sound if you stroll through in open forests this time of year. Males put on an elaborate show most evenings in early spring. After repeated “peents,” he flies upward in a spiral, reaching a height of about 300 feet. Then he begins chirping as he dives back down in a zig-zag pattern, landing right next to his chosen female.
Read how renowned nature writer Aldo Leopold described the woodcock mating ritual in A Sand County Almanac.
(Image courtesy Lynette S./Flickr)
This bright green, large-leaved wetland plant that appears in early spring may actually help melt leftover snowfall. Skunk cabbage generates temperatures up to 59-95 degrees above the air temperature, allowing the plant to literally break through frozen ground and sprout when temperatures are still too cold for other plants to sprout.
The plant’s foul odor attracts pollinators, including flies and bees, and discourages predators.
Hurricanes, earthquakes, a freezing cold winter and a blistering hot summer – 2011 has been an interesting year for weather in the Chesapeake Bay region. Scientists with the Smithsonian Environmental Research Center have written some preliminary thoughts about the bizarre weather and its link to conditions in the Bay in a post on SERC’s blog, Shorelines.
While SERC tends to focus on the long-term picture rather than brief snapshots, this year has prompted more than a few raised eyebrows among our scientists. What does it mean for the environment? What does it mean for Chesapeake Bay? And can any of it be linked to climate change?
Visit SERC’s blog to read more about the link between 2011 weather and the Chesapeake Bay.
Image courtesy Iris Goldstein/Flickr
Plumes of sediment were observed flowing down the Susquehanna River into the Chesapeake Bay this week after the remnants of Tropical Storm Lee brought heavy rainfall to Pennsylvania and Maryland.
The large rainfall totals caused rivers to swell, washing dirt and pollution off the land and carrying it downstream to the Bay. Record flooding and water levels were recorded at Conowingo Dam on the Susquehanna River last week.
Image courtesy NASA/GSFC/MODIS
Scientists with the U.S. Geological Survey (USGS) measured a near-record flow of 775,000 cubic feet per second (CFS) at Conowingo Dam on the Susquehanna River on the morning of Friday, Sept. 9. The river is expected to reach the third-highest flow in history this weekend, ranking behind the June 1972 flow of 1,130,000 cfs and the January 1996 flow of 909,000 cfs.
2011 will most likely be one of the highest annual flow years on record for the Susquehanna River due to wet spring weather and the September tropical storms Irene and Lee. High river flows are also being measured throughout other parts of the Bay watershed. (Visit the USGS’s real-time streamflow website for more information about the region’s river flows.)
Scientists expect that the sheer magnitude of the flood waters – which carry nutrient and sediment pollution from the land to the water – will have a negative effect on the Bay’s health. Some concerns and potential effects of the flooding include:
Timing makes a big difference in whether flood events have a short-term or long-term effect on the Bay’s health. Because these storms occurred in late summer, the Bay Program expects that there will be fewer long term impacts to the Bay ecosystem. September is the end of the peak growing season for bay grasses and is not a major spawning period for aquatic life. Additionally, cooler temperatures should prevent large algae blooms from growing in response to excess nutrient pollution.
It will take time for Bay Program partners to monitor and assess conditions before the true impact of the rain events is known. Maryland and Virginia are working closely with scientists from universities, the U.S. EPA and NOAA to expand monitoring of the Bay and its tidal rivers in the coming days and weeks. The USGS is working with the six Bay states, the District of Columbia and the Susquehanna River Basin Commission to measure nutrient and sediment pollution at key monitoring sites as part of the Bay Program’s non-tidal water quality monitoring network.
When it became clear that Hurricane Irene would move through the Bay region, the Chesapeake Bay Program’s (CBP) monitoring program coordinators, like Bruce Michael at Maryland’s Department of Natural Resources, adjusted the Bay water quality monitoring cruise schedules to get data just following the hurricane.
Now in the days since the hurricane, recent data from Maryland’s Eyes on the Bay program is showing that the Bay received a short term water quality boost from the hurricane. This is a result of the physical mixing of the Bay’s waters by extreme winds and waves that sent oxygen-rich surface waters into the deeper channels that are normally lacking oxygen at this time of year.
When it comes to hurricanes and their impact on the Bay, it’s the timing that makes the big difference in terms of whether there is a short term (weeks to a month) or a long lasting (months to years) impact on the Bay ecosystem.
In this case, timing is made up of two important components: the point during the hurricane season when the hurricane moves through Bay country and how long the hurricane lingers over the Bay and its surrounding watershed.
When hurricanes strike during important growing seasons for fish, oysters and underwater bay grasses, the results can over longer lasting effects. Hurricane Agnes back in 1972 (a tropical storm by the time it hit the Bay), hit in June at the peak of the underwater Bay grasses growing season, tipping an already declining Bay ecosystem into a tailspin lasting into the early 1980s.
Also, when a hurricane stalls and hangs around the Bay and its watershed for days, the amount of rain and resultant flooding can increase dramatically compared to the effects of Irene who moved all the way through the region over in less than a 24-hour period.
Fortunately in the case of Hurricane Irene, we are at the tail end of the peak growing season for bay grasses, so the clouded water and increased amounts of sediments entering the Bay’s tidal waters via runoff will not have as big of an impact compared to if the hurricane hit us in June or July.
We are also not in prime oyster spawning season (later in the fall to early winter) nor are we in any critical fish spawning period (late winter to late spring) so we missed those opportunities for a bigger, more direct impacts on our fish, crabs, oysters and grasses.
Unlike Hurricane Isabel, Irene’s track and, therefore, wind directions meant that we did not experience a devastating storm surge that resulted in the extreme shoreline erosion the region witnessed in the fall of 2003.
The flood waters will continue to bring in extra nutrient and sediment pollution loads into the Bay for days and even weeks to come. But again, timing is on our side. With cooler temperatures and shorter days coming, those excess nutrients will not feed algal blooms which love hot, sunny, calm days.
Some of the excess nutrients that flowed downstream during the storm will remain in the Bay’s tidal waters and will support next year’s algal growth. However their impact is likely less than if the hurricane had struck later in October or November when the nutrients have a greater opportunity to hang around until the next year.
The bottom line on Hurricane Irene’s impact is that we will have to wait for weeks (mixing up of the water column with good oxygen levels; short term algal blooms), and really months (impact on the next spring’s algal blooms, early summer’s re-growth of underwater Bay grasses, and mid-summer’s dissolved oxygen conditions years), to fully answer the question, “What was the impact of Hurricane Irene (and even the fall 2011 hurricane season) on the Bay?”
Fortunately, the CBP partnership has an extensive monitoring program in place which continues to measure various indicators of the Bay’s health — in this case, prior to the hurricane and in the weeks and months following the storm.
Given the timing of this storm, the Bay likely dodged a potentially serious bullet thanks to Irene’s timing, rapid movement through the region, and track.
For more information about the effects of Hurricane Irene on the Chesapeake Bay, visit these links from our partners:
We've been getting a lot of rain in the Chesapeake Bay region this spring. One day after a rain storm a few weeks ago, we decided to go around the neighborhood to see what trash we could find on the street.
After an hour, we had picked up about half a garbage bag full of trash. Our route along an Annapolis street led us to a storm drain that was located directly above a small creek. All of the trash we picked up that day would eventually have gone into the storm drain and then into the creek it flows to. How? Rain!
Rain picks up trash and other pollutants and washes them into storm drains, which flow to our local streams, creeks and rivers. And our local waterways flow to the Chesapeake Bay. This is why you should always pick up your trash!
Welcome to the latest entry in our "Ask a Scientist" series! Each month, we take a question submitted through our website or Twitter (@chesbayprogram) and have a scientist from the Bay Program partnership answer it here on our blog.
Today’s reader question is about the effect of spring rainstorms on the Chesapeake Bay's health. We asked Scott Phillips, Peter Tango and Joel Blomquist, scientists with the U.S. Geological Survey and members of the Bay Program’s Nontidal Water Quality Workgroup, for their explanation on why heavy rains have such a big effect on the Bay and its local rivers.
They say April showers bring May flowers. But around the Chesapeake Bay, rainstorms bring a whole lot more.
The rain and snow that falls on the Bay watershed, an area of land that stretches from New York to Virginia, drains into local streams and rivers, which eventually flow to the Chesapeake Bay. About half of the water in the Bay comes from its rivers; the other half from the Atlantic Ocean.
The U.S. Geological Survey measures river flow throughout the Bay watershed and estimates the amount of fresh water that enters the Bay each month and year.Typically, 52 billion gallons of water drain into the Chesapeake Bay each day.
The river water that flows into the Bay has a significant impact on the Bay’s water quality, habitats, and fish and shellfish. Spring rains affect the amount of pollution going into the Bay. During periods of higher river flow, more nutrient and sediment pollution enters the Bay. During dry periods, fewer pollutants are washed into streams and carried into the Bay. In general, river flow into the Bay is highest during the spring, when there are more rain storms.
This past March started with noteworthy flooding across the watershed. River flows in March were some of the highest ever recorded. Field crews mobilized to collect nutrient and sediment samples that help determine the amount of pollution that washed into the Bay.
Too many nutrients and sediment contribute to pollution in the Bay and local streams. Elevated nutrient levels in the Bay tend to cause excessive algal growth. As algae decay, dissolved oxygen levels drop. This leads to unhealthy conditions for fish, crabs and other underwater life. Algae and sediment also block out sunlight that underwater grasses need. For these reasons, Chesapeake Bay Program partners are working to reduce these pollutants.
River flow also affects the salinity, or amount of salt, in the Bay’s water. The Bay’s salinity ranges from fresh water near the top of the Bay at Havre de Grace, Maryland, to ocean water near Norfolk, Virginia. In dry years, there is less river flow so saltier water moves further up the Bay. During wet springs, more fresh water enters the Bay, pushing salty water farther south.
Changes in salinity affect fish, oysters and underwater bay grasses. For example, some underwater grasses cannot survive if the water is too salty, while others can only survive in fresh water. Diseases spread to more oysters in saltier waters. Finally, sea nettles are more common in saltier water. So salinity and river flow influence our choice of places to swim to avoid frequent and painful jellyfish stings!
Early March's heavy rains and snow melt caused a flood of nutrients and sediment to flow into the Chesapeake Bay from the Susquehanna River, according to scientists with the Maryland Department of Natural Resources.
This heavy runoff, which resulted in record poor water clarity in many areas, could harm bay grasses and cause more algae blooms to form in the Bay this spring and summer, especially if the wet weather continues.
Two days after a very heavy rainstorm that doused the region with 2+ inches of rain, the U.S. Geological Survey recorded a peak flow of 485,000 cubic feet/second (cfs) from the Susquehanna River at Conowingo Dam. This was well above the March average of 75,000 cfs and the highest average daily flow rate observed at the dam since September 2004, when floodwaters from Tropical Storm Ivan passed through.
Large amounts of fresh water flowing from the Bay’s rivers can erode stream banks and bring polluted runoff from the land into the Bay. Late winter and early spring are critical times for many of the Bay’s aquatic species. Bay grasses are just beginning to grow and many fish are starting to spawn.
Maryland DNR will continue to monitor water conditions to assess any short- or long-term storm effects of the wet weather.
For more information, visit Maryland DNR's website.
Welcome to the latest installment of the BayBlog Question of the Week! Each week, we take a question submitted on the Chesapeake Bay Program website or a frequently asked question and answer it here for all to read.
This week’s question is all about the wet weather we’ve had in the region lately: “What effect does heavy rainfall have on the Bay?”
The amount of rainfall the Chesapeake Bay region receives affects the amount of water that flows into the Bay from its rivers. This is called river flow. When we get more rain, it increases the amount of nutrient and sediment pollution that gets into local streams and rivers, and eventually the Bay.
When it rains, stormwater runs off lawns, farms, streets and parking lots, picking up pollution and carrying it into the nearest storm drain or waterway. A lot of rain can also erode stream banks, which causes more sediment to make its way to the Bay. Excess nutrients and sediments are harmful because they block sunlight from reaching bay grasses. Excess nutrients also fuel the growth of algae blooms that can lead to low oxygen levels.
But heavy rainfall can also carry with it much more visible signs of pollution: namely, trash.
The Baltimore Sun’s B’More Green Blog posted some compelling photos this morning, taken at the Inner Harbor in Baltimore by the National Aquarium. It seems that not only did all the rain likely carry a lot of nutrients and sediment into the Bay, it also "trashed" the harbor.
The EPA has officially dubbed Baltimore’s Inner Harbor as “impaired” by trash. The Anacostia River watershed in Washington, D.C., has a similar, if not more severe, issue. The Anacostia recently became the first interstate river to have a Clean Water Act “trash pollution diet” imposed on it.
If there's one good thing about all this rain, it's that seeing all the trash it carries into our local waterways reminds us to try and minimize the trash we use in our day-to-day routines. After all, do you want to be swimming with a bunch of old coffee cups -- or eating seafood that has been doing the same?
Do you have a question about the Chesapeake Bay? Ask us and we might choose your question for the next Question of the Week! You can also ask us a question via Twitter by sending a reply to @chesbayprogram! Be sure to follow us there for all the latest in Bay news and events.
After a long, cold winter full of snow, ice and disrupted plans, many people in the Chesapeake Bay watershed are looking forward to the first signs of spring. Throughout the region, there are plenty of little signs that the season is about to change, from the return of familiar fish and birds to the departure of the region’s winter visitors.
Whether good or bad, these six signals should give you a little bit of hope that the winter blues will soon be relieved by the warmer days of spring.
The tundra swan migrates to the Chesapeake Bay region in the fall and stays here through the winter. But once spring approaches, these beautiful white birds begin to leave the area and migrate back to the arctic tundra, where they will remain to breed and live through the summer. Observing a mass exodus of tundra swans – which leave just the invasive mute swan in our area for the rest of the year – is a sure sign of spring’s arrival.
After wintering in the Caribbean and South America, local legend has it that ospreys return to the Chesapeake Bay region by St. Patrick’s Day every year. Ospreys are often spotted in the region before this date, though, as they seem to be guided by daylight and can sense when days are beginning to get longer. Because ospreys are relatively tolerant of human presence and nest in close proximity to people, it shouldn’t be too much longer before you start to see a few ospreys building their nests in the area.
One of the earliest and truest signs of the coming of spring is the emergence of skunk cabbage, a fragrant plant that often appears in the Bay region as early as February, fighting through snow to reach the surface. While many associate the coming of spring with pleasant-smelling flowers, skunk cabbages emit a rather unpleasant aroma. Nevertheless, it is a sign that the wetlands where the plant grows are beginning to soften as temperatures rise and spring makes its way to the region.
The spring peeper frog is one of the first to call and breed during the spring, making the peeper’s shrill call another sure sign of the change of seasons from winter to spring. The peeper emits a single, clear “peep” once every second beginning in March.
As temperatures begin to rise, shad make their way back “home” to the Chesapeake Bay from the ocean to spawn during the spring months. They are said to follow their uncanny sense of smell back to the same river or stream where they were born. Males arrive first, soon followed by females.
Shad runs have always been a cause for celebration in the Chesapeake region, beginning with Native Americans and continuing today. Many towns in the region have annual shad festivals to celebrate the fish’s spawning runs. A native plant called the shadbush, which grows on the edge of forested wetlands, blooms in March to coincide with the return of its namesake, the shad.
An unwelcome signs of spring in the Bay and its rivers is the return of algae blooms, which can block sunlight from reaching underwater bay grasses that are just starting to grow. Each spring, as snow from winter storms melts and heavy spring rains begin, nutrients are washed into local waterways and algae blooms make their unwanted return, an unfortunate but sure sign of warmer weather in the Chesapeake Bay region.
Welcome to this week’s installment of the BayBlog Question of the Week. Each week we'll take a question submitted through the Chesapeake Bay Program website and answer it here for all to read.
This week’s question comes from Daniel, who came to our website seeking information about the effects of road salt on the Chesapeake Bay and its local waterways. He said, “With all the information that is out there about the pollution in our Bay…it seems like we have created another major source of pollution by throwing all the salt into the Bay.”
Much of the Chesapeake Bay watershed has experienced record-breaking snow storms this winter. With roads covered in snow and ice, road crews had to use the most effective deicer at their disposal: salt, and lots of it. Controversy struck when it was announced that plows in Baltimore would begin dumping snow from the roadways into the Inner Harbor. What would all of that salt do to the water? Isn’t there a better way to handle it?
While public safety was the most important factor during these major snowstorms, the decisions made by public officials also took environmental concerns into consideration.
Dumping snow into the Inner Harbor or the Chesapeake Bay, which are already brackish (a combination of salt and fresh water), is not necessarily bad because salt is already present in the water. However, dumping salt-treated snow into freshwater streams and creeks is dangerous because it can drastically change the amount of salt in the water, harming the freshwater species that call these waterways their home.
Of course, even without dumping snow directly into a body of water, salt will end up there as snow begins to melt and run off our streets, lawns and driveways. Since runoff is the fastest growing source of pollution to the Chesapeake Bay, scientists in the region will closely monitor the effects of snow melt and runoff.
The runoff caused by snow melt, however, is generally more gradual than that of a strong rain storm, giving road salt and other pollutants more time to absorb into the ground, where they can be filtered out by trees and vegetation. Heavy rainfalls, on the other hand, accelerate the speed at which polluted runoff flows into streams, rivers and the Bay.
To get back to the question from Daniel, yes, the salt used on roadways during snowstorms can become a pollutant in the Chesapeake Bay and local rivers, creeks and streams – but so can fertilizers, dirt, oil, trash and other substances carried by runoff into waterways. There are other deicing agents that could be used, but most are more expensive and some have not yet been tested for environmental effects.
Since this year was a rarity in terms of snowfall for most parts of the Chesapeake Bay watershed, hopefully the problem of too much road salt and snow melt won’t be something we’ll have to address very often in the future!
Do you have a question about the Chesapeake Bay? Submit it on our website and it could be our next Question of the Week!
Welcome to the latest installment of the BayBlog Question of the Week! Each week we take a question submitted through the Chesapeake Bay Program website and answer it here for all to read.
This week’s question is one a lot of people have been asking in recent days: With the nor’easter from Hurricane Ida blowing through the region, high winds, flooding and stormwater are on everyone’s minds. So what effect does a storm like this November nor’easter have on the Chesapeake Bay?
The amount of rain that falls on the Bay watershed has a direct effect on river flow, which is the volume of fresh water that flows into the Chesapeake from its tributaries. Typically, fresh water makes up about half of the Bay’s entire volume. When large amounts of rain fall in the region, such as during this nor’easter, it can tip the balance of fresh and salty water in the Bay.
A major issue associated with more rainfall is an increase in stormwater runoff, which carries dirt, trash, nutrients and other pollutants from our roads, lawns and parking lots into the Bay and its local waterways. Once in the water, this pollution can fuel the growth of algae blooms and harm underwater life, including crabs, oysters and bay grasses.
We’re already seeing the effects of this storm in Virginia, where officials have implemented a temporary ban on shellfish harvesting. The fear is that clams, oysters and scallops could become contaminated due to human and animal waste being washed into the Bay from tidal flooding.
High tides and flooding are certainly of concern to those who live by the Bay’s shores, but large storms like this have an effect on every stream, creek and river throughout the region. You can do your part to minimize the impact of storms and eliminate as much pollution as possible by picking up litter on the ground and covering bare spots in your yard to reduce erosion.
For more information about how weather affects the Bay and its watershed, check out our weather page.
Do you have a question about the Chesapeake Bay? Please send it to us through our web comment form. Your question might be chosen for our next BayBlog Question of the Week!
Autumn makes you think of pumpkin pie, hot apple cider and the earthy smell of fallen leaves. I am thankful we get to experience all four seasons here in the Chesapeake region – even though I’m not as fond of the ice storms winter brings to us in Maryland.
See what the Chesapeake looks like today in each season by visiting NASA's website. It is amazing how the landscape changes from spring to summer to fall to winter.
A hot, steamy summer has settled on the Bay watershed, bringing scorching temperatures and high electric bills. The news has been filled with reports of poor air quality and power outages, and we still have over a month of summer left.
But high temperatures affect a lot more than our sweat glands and wallets; they impact the Chesapeake as well. Although it is America's largest estuary, the Bay is surprisingly shallow, with an average depth of about 21 feet. (In contrast, Lake Michigan has an average depth of 279 feet.) Because of its shallow nature, the Bay suffers large seasonal fluctuations in temperature.
As summer water temperatures rise, it lessens the water's capacity to hold dissolved oxygen, which is vital to a host of creatures, from blue crabs to striped bass. The warmer the water gets, the less oxygen it contains. When combined with tons of nutrients and sediments, the heat spells trouble for the Bay in the form of numerous anoxic “dead zones.” These areas are becoming an annual summer problem in the Bay's deep channels.
High water temperatures may also affect underwater grass beds. Last year, warmer than average water temperatures may have caused the large scale loss of eelgrass in Tangier Sound. And while high temperatures can negatively affect SAV, they aid in the growth of something not so desirable: algae. These tiny plants flourish in the hot summer sun, soaking up rays and nutrients, but often multiplying to unhealthy proportions. These harmful algae blooms can block out sunlight needed by SAV, or produce toxins that kill fish and sicken humans.
If you are interest in ways to combat the problems facing the Bay, check out our list of ways you can help. Maryland DNR also offers the latest information on harmful algae blooms.