Historic flooding events have dominated the news this week as heavy rain and snowmelt pummel the Midwest. While we may feel powerless during flooding events, we have the power, with help from CWPPRA, to restore… More
Hydrologic Restoration and Vegetative Planting (BA-34-2)
Problems:
The Lac des Allemands River Basin Initiative identified the following specific problems within the Lac des Allemands Watershed: drainage impairments; water quality impairments; loss of marsh; and decline of cypress forest. Many years of study by Louisiana State University researchers in these swamps have demonstrated that, because of impoundment, subsidence, and inadequate accretion of sediments and organic matter, some areas are already highly stressed and converting to open water, floating aquatic plants, and fresh marsh. Also, the Coast 2050 report suggests that other areas of the swamps throughout the basin will likely convert to open water or floating marsh by the year 2050. These problems are caused by the loss of river water along with the associated sediment and nutrients necessary for swamp health. The loss of river water can be attributed to the leveeing of the Mississippi River. Impoundment caused by roads, drainage canals, and spoil banks is also a major cause of degradation of these swamps.
Restoration Strategy:
The original proposed restoration strategy included installing two small siphons (averaging 400 cubic feet per second) to divert water from the Mississippi River; gapping spoil banks on Bayou Chevreuil; gapping spoil banks along the borrow beside Louisiana Highway 20; installing culverts under Louisiana Highway 20; improving drainage in impounded swamps; and planting cypress and tupelo seedlings in highly degraded swamp areas.
The proposed diversion from the Mississippi River was to bring fresh water, fine-grained sediments, and nutrients into the upper des Allemands swamps, which would have helped maintain swamp elevation, improve swamp water quality, and increase productivity and regrowth of young trees as older trees die. However, after hydrologic modeling and more detailed engineering/design and cost estimation, it was determined that the siphon would cost far more than originally anticipated. For that reason, the CWPPRA Task Force approved the project sponsors’ request to re-scope the project to eliminate the siphon feature, and to focus on the remaining project features.
Location: The project is located West of Lac des Allemands in St. James Parish, Louisiana, south of the town of South Vacherie, bordered on the south by Bayou Chevreuil, and on the east by LA Highway 20.
Progress to Date: The Louisiana Coastal Wetlands Conservation and Restoration Task Force approved Phase 1 funding in January 2001. In June 2013, the Task Force approved a request to change the scope of the project to eliminate a siphon feature and focus on the remaining original hydrologic restoration and vegetative planting project features. The Louisiana Coastal Protection and Restoration Authority performed the engineering and design services. Design was completed in October 2015 and Phase 2 funds for construction was approved by the Task Force in January 2016. Construction activities for excavation and placement began in October 2017 and ended on December 20, 2017, vegetative plantings occurred in late January, and officially completed on February 2, 2018.
The three (3) principal project features included:
1. Eight (8), 400-foot-long, strategically designed gaps were cut in the northern Bayou Chevreuil spoil bank to reverse the effects of impoundment;
2. Sixteen (16) spoil placement areas were created on each side of the channel banks; (1 placement area on both sides of each gap) to beneficially use the dredged material on site;
3. Seven hundred (700) Bald Cypress and one hundred (100) Water Tupelo saplings were planted in the constructed spoil placement areas to start swamp regeneration and swamp productivity.
This project enhanced 2,395 acres of swamp habitat that would have continued to degrade without the project.
This project is on Priority Project List (PPL) 10.
The sponsors include:
Federal Sponsor: U.S. Environmental Protection Agency
Local Sponsor: Coastal Protection and Restoration Authority (CPRA)
Classifying Wetlands Part 2
Last week’s Wetland Wednesday mentioned 3 main criteria as part of identifying a wetland (wetland hydrology, hydrophytic vegetation, and hydric soils). – Today we’ll look at how plants and soils help scientists delineate wetlands.
In the field, scientists identify and sample soils and plants as part of wetland delineation. The LSU AgCenter groups plant species based on where the plant is naturally found as seen in the table below.
Wetland plants have adapted to flooded soils. “Obligate” plants can tolerate water at high levels or when soil saturation is a normal condition to that area. Examples of these plants include the bald cypress (Taxodium distichum), or cattail (Typha latifolia) [3].
In contrast, plants that cannot handle flooded conditions for an extended period would naturally be in the “upland” area of land (i.e. winged sumac (Rhus copallina), eastern redbud (Cercis canadensis), or panic grass (Dichanthelium sp.) [3].
People delineating wetlands focus on a project area according to aerial and soil maps along with aerial photographs [1]. Delineators then take soil samples and determine characteristics seen in hydric soils which relate to cycles of flooding and drying. – Examples of those include oxidized soils, hydrogen sulfide (rotten egg smell) and organic bodies found on plant roots. Finally, the plant and soil types are compared, tested, then matched to determine wetland boundaries for mapping and policy purposes [1].
Wetland delineation is a tool for protecting and documenting these important landscapes which contribute to a healthy and functional environment. It is important to note that wetland delineation requires much more than just plant and soil identification. CWPPRA utilizes sound science, engineering, mapping, and geo-technical surveys in the process of planning, approving, constructing, and maintaining coastal Louisiana wetland restoration projects.
Sources:
[1] Bedhun, Rebecca. 2018. “Watch and Lean Now: How To Do A Wetland Delineation”. Shoret Elliot Hendrickson Inc. Available: http://www.sehinc.com/news/watch-and-learn-now-how-do-wetland-delineation [September 9, 2018]
[2] Jon Kusler. “Common Questions: Wetland Definition, Delineation, and Mapping”. Association of State Wetland Managers, Inc. Available: https://www.aswm.org/pdf_lib/14_mapping_6_26_06.pdf [September 9, 2018]
[3] LSU Ag Center. 2018. Louisiana Plant Identification: Plant List. Available: http://www.rnr.lsu.edu/plantid/listcommon.htm [September 10, 2018]
Classifying Wetlands Part 1
When we think of wetlands, our mind may paint a picture of a swampy area with open water, and maybe a heron or alligator. Despite common perception, not all wetlands are the same. — These watery features come in all shapes, sizes, and locations along with a unique system of processes and purpose.
Wetlands are diverse and the difference between dry and wet environment lies along a gradient. Therfore, there cannot be one perfect definition to represent what a wetland is. Scientists have developed criteria to identify wetlands and aid in assessment, inventory, and management [1].
Figure 1. An example used by scientists to start the process for wetland delineation.
| Criteria | Definition |
| Wetland hydrology | the gradient or degree of flooding or soil saturation across a landscape [2]. |
| Hydrophytic vegetation | plants adapted to grow in water or in a soil that is occasionally oxygen deficient due to saturation by water [2]. |
| Hydric soils | soils that are sufficiently wet in the upper root zone and may develop anaerobic (oxygen lacking) conditions during the length of at least 1-2 growing seasons [2]. |
As seen below in Figure 2 and 3; some wetlands are flooded year-round while other water levels fluctuate. The wetland hydrology differs depending on location and the geography of the landscape.
Figure 2: A simplified example of a wetland water gradient dependent on elevation and tidal ranges.
Figure 3.
You may not live close to a coastal marsh, but many water sources eventually connect to a wetland on the coast, making the streams, lakes, and swamps in your backyard an important link to the larger watershed. That’s why it’s important to support, respect, and appreciate the water systems and land of everyday life. CWPPRA projects restore and protect these systems to support the livelihood and cultures of Louisiana and to protect the land we value so dearly.
In next week’s edition of Wetland Wednesday, we’ll look at how scientist use vegetation and soils to classify wetlands!
Source:
[1] Fish and Wildlife Service. Classification of Wetlands and Deepwater Habitats of the United States. Available: https://www.fws.gov/wetlands/documents/Classification-of-Wetlands-and-Deepwater-Habitats-of-the-United-States-2013.pdf [August 27, 2018].
[2] Natural Resources Conservation Service. Hydric Soils Overview. Available: https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/use/hydric/?cid=nrcs142p2_053985 [August 27, 2018].
Hurricanes
This week marks 13 years since Hurricane Katrina, an event some citizens of Louisiana are still recovering from. We may have all heard the name, but do we know what a hurricane is, how wetlands are affected, and how coastal landforms can decrease hurricane impacts?
“Hurricanes” are low-pressure tropical storm systems that differ from other storms in severity as well as location. A hurricane is a storm with winds above 64mph accompanied by heavy rain that originates in either the NE Pacific or the N Atlantic Ocean (the oceans that touch the USA). Due to a phenomenon called the Coriolis Effect, hurricanes rotate counter-clockwise, whereas a southern hemisphere storm would rotate clockwise. Hurricanes develop a characteristic “eye of the storm” in the center, which is an area of low pressure and low wind. Just outside of the eye is the most severe weather, the eyewall, with winds reaching up to 210mph in the strongest storms! Hurricane “category” ratings are as follows:
- Category 1: 74-93mph
- Category 2: 96-109mph
- Category 3: 110-129mph
- Category 4: 130-157mph
- Category 5: >158mph
Hurricanes develop over areas with warmer waters, typically nearer the equator, and move away from the equator. [1] Coastal Louisiana is hit by hurricanes on an increasingly regular basis, and those hurricanes all develop in the North Atlantic Ocean in late summer and fall. Our “Hurricane Season” occurs from June through November each year. [2] Several aspects of hurricanes pose major threats to our wetlands statewide. High winds can topple trees, rip up shrubs and grasses, and move sediments around. High rainfall can cause flooding in areas that are not well-adapted to high-water conditions. Storm surge can push saline seawater into brackish and freshwater systems. Hurricanes cause massive disturbance in coastal wetlands, but wetlands are a crucial barrier that protects major cities from taking as much damage. CWPPRA works to combat land loss and protect the future of coastal Louisiana.
Some CWPPRA projects restore barrier islands, which are natural defenses that develop in the Deltaic Cycle. Barrier islands lessen storm surge during hurricanes, bearing the brunt of the waves. Sadly, they cannot provide perfect protection because they are degrading, but they are not the last line of defense. We still have coastal marshes that are great at storing water and acting like a speed bump to storm surge. It is estimated that each mile of coastal marsh decreases storm surge by about a foot. Unfortunately, many coastal marshes are decaying into open water and are no longer protective barriers. CWPPRA will continue to restore wetlands and nourish barrier islands to #ProtectOurCoast!
[1] https://en.wikipedia.org/wiki/Tropical_cyclone
[2] https://www.ready.gov/hurricanes
Featured image from [1]
Goose Point/Point Platte Marsh Creation (PO-33)
Interior ponding and, to a lesser extent, shoreline erosion are the major causes of wetland loss in the project area. Loss rates were highest during the period from 1956 to
1978. Those high loss rates were associated with hydrologic alterations which allowed salt water to penetrate the fresher marshes. During the transition to a more brackish plant community, large ponds were formed. A narrow strip of land separates those ponds from Lake Pontchartrain. Although the shoreline erosion rates are relatively low, the shoreline is already breached in several areas, and marsh loss in the interior ponds is expected to increase if the shoreline fails.
The goal of this project is to re-create marsh habitat in the open water behind the shoreline. This new marsh will maintain the lake-rim function along this section of the north shore of Lake Pontchartrain by preventing the formation of breaches into interior ponds. Sediment will be dredged from Lake Pontchartrain and contained in cells within the interior ponds to create approximately 417 acres of marsh. In addition, 149 acres of degraded marsh will be nourished with dredged material. Marsh will be created to widen the shoreline so that the ponds will not be breached during the course of normal shoreline retreat.
The project is located on the north shore of Lake Pontchartrain between Fontainebleau State Park and Louisiana Highway 11 and within the Big Branch Marsh National Wildlife Refuge in St. Tammany Parish, Louisiana. The project area at Goose Point also includes a portion of the St. Tammany State Wildlife Refuge.
On February 12, 2009, a final inspection of the project site was conducted. All construction activities are complete. This project is on Priority Project List 13.
The Federal Sponsor is USFWS
The Local Sponsor is CPRA
Coastal Cultures: Isleños
In a conference call with our Outreach Committee last week, a committee member reminded us to discuss the human component in our Habitat Toss outreach activity. We’re taking it a step further and turning our focus to various ethnic and cultural groups who settled the Louisiana wetlands and support themselves and their families through coastal industries.
Today, our focus is on the Isleños of Louisiana. During the late eighteenth century, these people originally immigrated to the United States from the Canary Islands, off the west coast of Africa. According to the official website, Los Isleños of St. Bernard Parish, Spain sent settlers from the Canary Islands to settle around New Orleans from 1778 to 1783 in response to British interest in Mexico. Since the Spanish had a large investment already in Mexico, they sent Canarians to establish settlements to counter British expansion towards Mexico, but instead, the new colonists formed communities that built strong ties to existing industry in the area. Four settlements were created by the Spanish for Canarians and other immigrants to live in and develop: Galveztown, Valenzuela, Barataria, and San Bernardo. For the first few years of each settlement, Spain subsidized costs and gave many of these new Canarian colonists (Isleños) land grants. Subsidies stopped in 1785 when the colonies became self-sustaining. San Bernardo became a successful agricultural community, thanks to the fertile soils of the lower Mississippi River Watershed. Under French Rule, the community was later renamed to St. Bernard.
In only seven short years, the Isleños established strong communities which later became major players in sugar, cattle, and several other farm crops. Some Isleños chose to leave their farms and joined the commercial fishing industry in the 1820s, ultimately becoming the Delacroix Island fishing community. Later in the century, the communities of Yscloskey and Shell Beach were founded through the same method.
Today, those communities are still heavily involved in the commercial fishing industry, but their homes are threatened by coastal land loss. CWPPRA has funded the design and implementation of several projects in that area. Though the history of St. Bernard Parish has been preserved for generations, it would be a tremendous loss to have such a historic area wash away due to preventable causes. It is for this reason that CWPPRA works to #ProtectOurCoast.
Find out more about the Islenos and their coastal legacy through the Los Isleños Heritage and Cultural Society website: http://www.losislenos.org/.
Green T. Lindon Elementary Math and Science Day
Last Friday, March 22, we spent the morning at Green T. Lindon Elementary School’s Math and Science Day. The Youngsville school hosted a variety of presenters throughout the school day, including KRVS 88.7FM, LASOAR, Lafayette’s Nature Station, a retired tennis instructor, and various UL Lafayette faculty members. Throughout the day, classes moved between stations around the school and explored multiple topics in math and science disciplines. Some of the available stations taught students about yoga, CrossFit, radio technology, bats, proper hand-washing protocol, tennis, and outdoor family recreation.
Our Public Outreach office brought three of our most popular games and split classes into groups and rotated through the three activities to learn about wetland types, inhabitants of wetlands, and wetland services. Wetland Jeopardy, led by intern Blair Miller, was played as a competition among students, Coastal Outreach Specialist Kacie Wright introduced students to a few wetland inhabitants through our Wetland Wonders boxes, and Outreach Coordinator Jennifer Guidry led our bean bag toss game that highlights the differences between three wetland habitats and the open ocean. Students rotated through the activities every 10 minutes before going to their next activity in another classroom or outside. One young student participated in Family Adventure Day the prior weekend and was able to lead the habitat toss game for his group, which was a great demonstration of our outreach activities’ impact.
We saw a total of 132 third graders in just two hours! We gave out stickers, magnets, and activity books. It was a fast-paced day full of excitement and we look forward to participating again next year.
Marsh Madness
Buckle up sports fans, because things are heating up, and not just on the college basketball court. CWPPRA projects are putting their best foot forward to land a spot in the next round of competition. There are 22 contending players going into a free-for-all to win a spot on CWPPRA’s roster. This draft means a lot to the strength of our team, so it is important that all the potential projects are in peak condition.
The CWPPRA project selection process is all about fundamentals. Projects are evaluated on how strong they would be on the defense for the United States national team and ranked accordingly. Task Force “coaches” are looking for projects that can block opponents such as hurricanes, will continue to develop after they join the team, and will work well with with other projects. Today, our contenders are practicing and refining their fundamentals before they have a shoot-out on April 11th on the technical committee’s home court in Baton Rouge. Technical Committee members will select a subset of 10 player projects that they think will be well-rounded to benefit team Louisiana and all its fans. That list of 10 projects will go on to the final round of the competition, and up to 4 will make the cut.
If you are a fan of coastal restoration, feel free to send us your draft picks for the upcoming vote! All the current stats for the candidate list can be found on our March 11 newsflash at https://www.lacoast.gov/ocmc/MailContent.aspx?ID=10119. We look forward to signing some of these exciting new prospects and we wish the projects luck!
Featured Image from https://www.pinterest.es/pin/380413499743991365/?lp=true
Boston Canal/Vermilion Bay Bank Protection (TV-09)
Construction of the Gulf Intracoastal Waterway, Boston Canal, and oilfield canals has greatly increased tidal exchange between Vermilion Bay and the adjacent marshlands to the north, particularly near their confluence with Vermilion Bay. This tidal exchange, combined with the effects of wave action from the bay and boat wake from traffic on the canal, has contributed to significant shoreline erosion along the Vermilion Bay shoreline. This same set of problems has also caused shoreline erosion along Boston Canal, particularly near its confluence with Vermilion Bay.
Rock dikes configured as sediment traps were constructed along the shoreline at the mouth of Boston Canal to promote sediment deposition and protect the shoreline and adjacent wetlands from continued wave-induced erosion. Vegetation was planted along 14 miles of the Vermilion Bay shoreline to act as a wave buffer and decrease shoreline erosion rates.
The project encompasses 466 acres of brackish marsh along approximately 16 miles of Vermilion Bay’s northern shoreline adjacent to Boston Canal. Running from the Oaks Canal to Mud Point, the project is located roughly 6 miles southeast of Intracoastal City, Louisiana, in Vermilion Parish.
Following the construction of the rock dikes, as much as 4.5 feet of sediment has vertically accreted in the lee, or windsheltered regions, of the structures. The dikes and vegetative plantings have increased vegetation cover, resulting in 57
acres of land growth. The shoreline has been stabilized at the mouth of Boston
Canal.
The survivorship and vegetation cover percentage along the shoreline were more pronounced in areas where native vegetation did not exist. Survivorship and percent cover were least pronounced when marshhay cordgrass (Spartina patens) was planted in established stands of roseau cane (Phragmites australis). Overall survivorship of planted smooth cordgrass (Spartina alterniflora) was over 90% after 12 months. Current coverage is nearing 100%. The 2005 OM&M Report concluded the sediment build-up behind the dike on the east and west sides is continuing and vegetation has taken over the exposed mud flats. Elevation data show an increase in sedimentation behind the rock breakwater.
This project is on Priority Project List 2.
Federal Sponsor: NRCS
Local Sponsor: CPRA
Lafayette Family Adventure Day
On Saturday, March 16, as part of Family Adventure Day, a fundraiser for Healing House, a non-profit in Lafayette offering grief counseling for children, families explored 42 stations around town. Each station offered a free activity that could engage family members of all ages. Our table was set up at the Louisiana Department of Wildlife and Fisheries (LDWF) headquarters near the Cajundome. Some of our neighbors were the US Fish and Wildlife Service (USFWS, one of our managing agencies), the Acadiana Park Nature Station, and LDWF .
At our station, families could hold baby alligators and touch a few different animal hides with LDWF; play with Einstein, the albino corn snake from the Acadiana Park Nature Station; practice their fishing technique, plant seeds for pollinators, or identify different bird species using binoculars with USFWS. Our public outreach office brought our habitat toss game that highlights the differences between wetland habitats in Louisiana and why an animal species would live in one habitat but not another, as well as give some examples of species that use more than one type of habitat. We also brought plenty of educational publications.
An estimated ninety families passed through the LDWF headquarters during the day , so we saw about 300 people over the course of the event. Families visited locations like the Lafayette Science Museum, the UL Marine Survival Training Center, Bayou Vermilion District, and more. Our posters, magnet sheets and stickers were popular with the kids, and several families signed up to receive WaterMarks.
Family Adventure Day is an annual event, so be on the lookout for next year! We had a great day and we appreciate LDWF and USFWS for hosting us this year. We would also like to thank all of the families who came to support Healing House and learn about our area’s wildlife. Please enjoy the attached photos of families engaging with us and our neighbors.
First Day of Spring
Spring is in the air! That means a burst of life in our coastal wetlands. You may already see flowers blooming, new leaves on trees, and a variety of migratory birds returning to their nesting habitat. Today, on the first day of spring, let’s explore the annual rebirth of Louisiana’s coastal habitats.
As plants proliferate in the warmer temperatures, so too a riot of colors joins the landscape. Some coastal favorites are seaside goldenrod (Solidago sempervirens), buttonbush (Cephalanthus occidentalis), and salt marsh morning glory (Ipomoea sagittata) for good reason: they produce attractive flowers that saturate the wetlands with color. Other plants have less colorful flowering and fruiting structures but are more prevalent. Many sedges (Family Cyperaceae) are beginning to put out their iconic inflorescences, the branching flower clusters, as are several grasses (Family Poaceae). Other popular marsh plants including Juncus and Spartina species also begin their pollination cycle. The reliable reproduction of these graminoid (grass-like) plants is helpful in CWPPRA marsh creation projects because those species repopulate new land more quickly than woody plants. Once they move in and put down healthy roots, they demonstrate the effectiveness of CWPPRA projects and their success!
Plant enthusiasts aren’t the only ones excited for springtime; wildlife watchers, especially birders, see an infusion of new plant growth and wildlife offspring. Many birds return from their wintering grounds in South America to the warm nesting grounds along the Mississippi Flyway. Songbirds like the beloved prothonotary warbler (Protonotaria citrea) fly across the Caribbean, the Gulf of Mexico, and our coastal waters to take advantage of the new plant life and insect population booms. South American migrants use the flyway to get further north alongside other species that use our coastal zone as a wintering habitat. Whether they are just stopping over or will be staying for the summer, Louisiana’s spring is one of the most exciting times to birdwatch. [1] Ultimately, birdwatching success diminishes at the same rate as our disappearing coastal wetlands. Habitat loss has major implications for population declines of bird species. Because birds have “favorite” wintering and nesting habitats, they are especially susceptible. Both their wintering and nesting habitats face the threat of deterioration and require protection. This part of the year is great for exploring all the natural areas that Louisiana has to offer, we suggest that you find a day that works in your schedule and visit a wetland near you; you’re bound to find something interesting. [2] We wish you all a happy spring and encourage environmental stewardship each and every day!
[2] https://www.crt.state.la.us/louisiana-state-parks/maps/index
