Coastal erosion is a global issue, causing an estimated $500 million per year in property loss and damage. Shoreline hardening, including rock jetties, groins and seawalls have unfortunately exacerbated this situation by deflecting and increasing wave energy directed at unprotected shores. Increasingly agencies, municipalities, and even engineering firms have begun to realize that natural vegetation can play a key role in maintaining beaches and reducing the loss of shorelines. Vegetation and reinforced vegetation both “roughen” and provide root reinforcement to the shoreline, serving to better absorb wave energy and dampen the forces of erosion. Read “Beach Erosion- What can be done?” via http://soilerosiononline.com/article-37-beach-erosion.html
Climate scientists predict that sea levels will rise by three feet — and could rise by as much as five feet — by the year 2100. What does this mean for some of the world’s coastal cities, or your favorite beach? The map below allows you to explore the regions of the Earth that are most vulnerable to sea level rise.
The culprit is thought to be the unfettered burning of fossil fuels. See the areas on the map in red? They could be under water by the end of this century if we don’t change our fossil fuel consumption habits.
Carbon absorption is critical to controlling carbon in the atmosphere. It turns out that created and restored wetlands are unexpectedly efficient for storing carbon.
Researchers and land managers need to consider restored and manmade wetlands as they look for places to store, or “sequester,” carbon long-term.
You may also like: Created and Restored Wetlands Are Unexpectedly Efficient for Storing Carbon
If you care about the protection and restoration of Montana’s streams and rivers, it’s time to let your voice be heard.
The Montana Department of Natural Resources (DNRC) has formally implemented a plan to require the use of large, non-native rip rap and/or concrete structures for all stream restoration and bank stabilization projects in the state. The recently released Draft 2012 Model Floodplain Ordinance clearly intends to deny the use of all “soft” approaches, like revegetation or the use of nominally-reinforced vegetation, through new requirements outlined on page 29, section 9 -12, of the draft ordinance.
The one-line requirement listed for stream restoration and bank stablilzation projects to withstand a 100-year flood event translates to an engineering requirement for hard rip-rap or hard structure. Although DNRC was requested to provide the state or federal law requiring stream restoration and bank stabilization projects to withstand the 100-year flood event, the agency failed to do so.
As is the case around the nation, Montana’s freshwater resources have been significantly damaged for decades as truckload after truckload of stone and concrete rip-rap have been dumped onto the banks of some of the states most precious headwaters. Armored floodplains cannot perform the same ecological services as healthy, well-vegetated floodplains. Healthy, well-vegetated floodplains naturally provide flood control, erosion control, and fish and wildlife habitat.
While agencies in Montana, including the U.S. Army Corps of Engineers and Montana Department of Environmental Quality, recognize the significant damage that has been wrought historically on Montana’s resources and are working to promote sound, and soft approaches to restoration here, some at the DNRC have belligerently stood firm in blind disregard of both best science and best practice.
The draft is open for public comment until June 10, 2012 on the DNRC website http://dnrc.mt.gov/wrd/water_op/floodplain/news/draft_model_ordinance.pdf
Anyone who has an interest in the health and productivity of Montana’s waterways should provide public comment to DNRC as well as take a moment to tell Montana Governor Brian Schweitzer that his agency is condemning the future of the state’s most valuable resources. Send a note to the Governor http://governor.mt.gov/cabinet/contactus.asp , and to Montana Department of Environmental Quality Director Richard Opper http://svc.mt.gov/deq/mail/recoverycontactusform.asp , asking them to help protect Montana’s streams and rivers from hard armor.
A stream or river is constantly adjusting itself. This is nature’s balancing act between the amount of water and gradient in the channel, and the amount and size of the sediment within the system. Any disturbance, either natural or human-caused, will change this balance. Activities such as building within the floodplain, constructing roads in riparian areas, or removing vegetation can limit a stream’s ability to maintain a healthy balance.
Residential or commercial construction within the floodplain does have an impact, as does protecting property by constructing dikes, levees, installing riprap, or eliminating overflows into side channels. The effects of these impacts within the floodplain can include increased peak flood levels, increased energy during a flood event downstream, increased bank and bed erosion on neighboring property, reduced habitat and reduced recreational values.
To limit or eliminate these impacts, avoid construction in the floodplain where possible; do not restrict floodwater access to side channels; and ensure construction within the floodplain minimizes disturbance of soils and vegetation. Contact THI to Learn More or Request Free Report
Back in 2003’s Global Environment Outlook Year Book, the United Nations Environment Programme (UNEP) declared the ocean’s “dead zones” the world’s top emerging environmental challenge. Now a recent report by UNEP says the number of dead zones, or low oxygenated areas in the world’s oceans, may have now grown to as many as 200, up from an estimated 150 in 2003.
Spreading dead zones have more than doubled over the last decade and are becoming the leading threat to commercial fisheries. The most well-known dead zone is in the Gulf of Mexico. Its occurrence has been directly linked to nutrients or fertilizers brought to the gulf by the Mississippi River.
Each summer, following spring flows from the Mississippi, the Gulf of Mexico experiences a massive die off of bottom-dwelling creatures like crabs and oysters, and sees an exodus of shrimp and fish from traditional fishing grounds along the coast. Scientists say the source of the Gulf’s now 8,000-square-mile dead zone is a condition of low oxygen levels, called “hypoxia,” largely caused by an influx of excess nitrogen from farm fertilizers, sewage and industrial pollutants.
U.S. Energy Policy and Dead Zones
In early 2008 scientists predicted the Gulf Dead Zone could grow to a record 10,000 square miles. The reason? According to the June 12, 2008 issue of U.S. News and World Report, U.S. farmers, encouraged by ethanol mandates and higher commodity prices, have expanded corn plantings and driven the acreage of other crops to record levels. Farmers along the Mississippi Valley are using more fertilizer, which contains nitrogen and phosphorous. These chemicals, when not used by crops, often find their way from farmland into water. Corn, because of its shallow roots, tends to be quite “leaky.” Excess nutrients lead to increased algal production and increased availability of organic carbon within an ecosystem, a process known as eutrophication. As the algae die and decompose, they consume oxygen, suffocating everything from clams and lobsters to oysters and fish.
Restoring Nature’s Water Filter
In July 2008 Hurricane Dolly stirred the gulf waters keeping dead zone expansion to a minimum. Scientists are testing floating, wave-powered pumps, designed to mimic the stirring effects of hurricanes. While these technologies may be of some use, Trout Headwaters, Inc. (THI), a private aquatic restoration firm based in Livingston, Mont., advocates a simpler, yet still challenging approach: Implementing policies and devoting our collective energies toward restoring and protecting nature’s own, perfect, water filter.
THI has worked with the U.S. Army Corps of Engineers and others to demonstrate improved, vegetative approaches to stabilizing and restoring streams and rivers in the Mississippi Delta. THI is dedicated to the development and application of state-of-the art technologies and treatments for restoring critical streamside or “riparian” vegetation. Healthy riparian vegetation acts to filter harmful pollutants, sediments and excess nutrients that wash into waterways from agricultural fields and urban areas.
Louisiana State University geologist Paul Kemp said in a National Public Radio interview that excess fertilizer wouldn’t be a problem if the Mississippi, and many of its tributaries, were still connected to their natural floodplains. The genesis of the Gulf’s dead zone was trying to control Mississippi flood waters, said Kemp, pointing out that, “Levees were built from almost the first day the Europeans set foot in Louisiana, so that means the modern river is well-separated from its delta.” After viewing many of the streams and rivers in the Mississippi Delta, THI President Michael Sprague agrees that the severe alteration of these stream channels is a serious, regional problem, and is troubled by an overuse of hard armor “riprap” lining many of those channels, which doesn’t offer the same benefits as trees and shrubs.
“Stream channelization, or straightening, and levee building has been rampant in the Lower Mississippi Alluvial Valley,” explains Sprague. “While this was done in an attempt to decrease flooding, the side effects have been more significant than we could have imagined.”
Healthy Riparian Vegetation Slows and Filters Runoff
Streams and rivers are meant to slowly meander and periodically overflow their banks in a complex hydrologic cycle of erosion and deposition. The problem, says Sprague, is the filter nature designed – diverse, streamside, woody vegetation that slows and purifies water before it enters streams and rivers – has been stripped from thousands of miles of Delta streams to make way for agriculture and development. The U.S. Department of Agriculture reports the Lower Mississippi Alluvial Valley has undergone the most widespread loss of bottomland hardwood forests in the United States. In Mississippi and Louisiana the U.S. Fish and Wildlife Service estimates more than 60 percent of native bottomland forests have been cleared, impacting many species of wildlife which once thrived in these floodplain ecosystems.
“When you combine channelization and levee building with the removal of riparian vegetation and bottomland forests, then throw in hard armor riprap lining stream banks, intensive agricultural practices that farm right up to the edge of streams, and ill-planned urban development, you get an ecological disaster like we’re seeing now through the Mississippi Delta and in the Gulf,” says Sprague. “This scenario has been repeated all over the world, and I applaud the UNEP for recognizing that unless we restore the health of our streams and rivers, not only will we see the collapse of freshwater and marine fisheries, like in the Gulf Dead Zone, we’ll begin to regret having squandered this country’s abundant supply of clean drinking water.”
Besides designing and installing more than 400 stream and wetland restoration projects across the U.S., Sprague’s company has completed several successful demonstrations of “green technologies” for river restoration and bank stabilization in the Mississippi Delta. “I’m hopeful we can turn things around. Now we know better so we’re doing better, and that’s half the battle,” said Sprague.
Riparian areas filter nutrients and improve water quality. In agricultural-use watersheds, nutrient filtering in riparian zones can help control agricultural nonpoint-source pollution. Sediment deposition is a natural process that takes place during periodic flooding. Accelerated upland erosion can increase sediment deposition in riparian and wetland areas because of downslope movement of dislodged soil material. Such deposition can change the soils, drainage, and vegetation associated with riparian or wetland areas (Lowrance and others 1985). Riparian vegetation also reduces sediment and nutrient transport in a number of ways. Roots, especially those of woody vegetation such as willows, help stabilize streambanks by holding soil intact. Vegetation also increases hydraulic resistance to flow, thereby lowering flow velocities and causing sediment deposition.
Another important role of wetland vegetation is uptake and long-term storage of nutrients. Wetland areas are more productive because of the nutrient and water subsidies provided by periodic flooding (Brinson and others 1980). Nutrient uptake into leaves and other deciduous parts can be an important factor in short-term nutrient storage. However, because deciduous plant parts drop each year, nutrients soon become available for transport. High litter fall and generally wet conditions also result in soils higher in organic matter.
In general, surface runoff slows as it flows through the riparian zone, causing sediment deposition and diminishing the water’s erosive potential.
The loss of wetlands is responsible, in part, for the change from perennial to intermittent flow in some streams. Many alluvial aquifers in the western United States are maintained by infiltration of upland runoff in the stream channel or alluvial deposits. These aquifers provide an important source of water for human use. Water storage in such aquifers was once partially responsible for maintaining base flow in western rivers, which are now dry beds much of the year. Learn more about restoring your increasingly precious natural resources.