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LAFOURCHE PARISH GAME AND FISH COMMISSION
Historic Habitat Changes
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Introduction
The Lake Field/Lake Long Game and Fish Preserve (Preserve) and surrounding area was built over the last 7,500 years through a series of overlapping Mississippi River delta lobes. The Teche Delta was active between 3,900 and 5,800 years ago and formed portions of the Terrebonne Bay estuary. After several additional deltaic lobes, a significant portion of the Mississippi River flow was diverted down Bayou Lafourche around 3,500 years ago, with maximum discharge rates reached about 2,000 years ago. The Mississippi River abandoned the Lafourche Delta about 700 years ago, but Bayou Lafourche remained a major distributary. During the early Lafourche stage, the major Bayou Lafourche distributaries flowed south along Bayous Terrebonne, Blue, and Black and the resultant subdeltas merged with the remnant Teche Deltas. In the late Lafourche stage, lower Bayou Lafourche became the chief distributary and a series of distributaries were formed first at Lockport and then later at Larose. The objective of this section is to provide a historic perspective on habitat and water quality changes and wetland loss within the Preserve. The Preserve and drainage basin as well as other Mississippi River deltaic plain wetlands have been greatly impacted by human-induced changes dating back to the early 1800s some of which were far removed from the physical boundaries of the Preserve but which peripherally impacted Preserve habitats. An early, pronounced habitat change within the Preserve was the decline in sizes of Lake Fields and Lake Long due to enhanced drainage and the cumulative addition of "flotant" marsh around the shoreline. Local historic habitat modifications that have directly impacted the Preserve includes transportation or draingage canals such as Company Canal and Hollywood Canal, drainage basin reclamation projects, petoleum-related activities, upper Bayou Folse watershed drainage improvements, and restoration projects sponsored by the Lafourche Parish Game and Fish Commission (Commission). Habitat modifications outside the Preserve and upper watershed that have peripherally impacted the Preserve included construction of the dam across Bayou Lafourche at the Mississippi River, levees along the Mississippi River, the Gulf Intracoastal Waterway, the Houma Navigation Channel, and the Company Canal Weir. Lake Fields and Lake Long Size Changes Lake Fields and Lake Long were larger during the early 1800s when the lake shorelines essentially coincided with their historic high water meander lines that defines the present boundary of the Preserve except for property that has been sold or transferred by the State of Louisiana. The shorelines retreated from the meander lines due to enhanced drainage and the cumulative creation of "flotant marsh" around the margin of the lake. Flotant marsh is created in sediment-deprived freshwater habitats when decaying organic vegetative material forms under a layer of live vegetation. As the underlying marsh substrate subsides, the mat eventually separates from the substrate and subsequently floats on the water surface. Approximately 70% of the fresh marsh within the Barataria-Terrebone estuary is flotant marsh. In recent years, the shorelines of both Lake Long and Lake Field have begun to retreat due to subsidence and shoreline erosion. Transportation Canals Early transportation canals in south Louisiana played a major role in the economic development and utilization of the area's natural resources. The absence of adequate ground transportation and orientation of coastal bayous in a north-south direction made movement in an east-west direction very difficult. These transportation canals were dug to connect and link natural bayous or rivers. Fresh marshes such as those found in the Preserve are very soft and were easily excavated by shovel or mechanical dredge even by early canal builders; however, transportation canals across the south Louisiana marshes presented problems because locks were necessary to prevent flooding during high water periods where the east-west canals intersected major waterways. Transportation canals (and oil exploration canals) have had significant impacts in coastal wetlands. Turner et al. (1991) estimated that canals and spoil banks may be responsible for at least 30-59% of Louisiana coastal wetland losses from 1955 to 1978. Wetland losses associated with canals are not only due to the direct impacts of converting wetlands into open water but also to the indirect impacts of altered hydrological patterns and increased salinity intrusion. The overall impacts of canals to the Preserve have not been quantified. Canals in the vicinity of the Preserve date back to the early 1800s. William Field, for whom Lake Field is named, purchased land in the vicinity of Lockport on both sides of Bayou Lafourche in January, 1823, and subsequently dug Field Canal which ran from Lake Field to the rear of Lockport. The old Field Canal was located about a block to the north of the present Company Canal in the vicinity of the current Barrios subdivision. The canal was used to transport goods that had been brought across Lake Field and Lake Long; the freight was then unloaded onto steamboats that traveled to New Orleans via the Mississippi River. Around 1860, the State of Louisiana funded several canal projects for drainage, including Bayou L'eau Bleu which was dug from the south end of Lake Long to Grand Bayou Bay to drain swamp lands. The Company Canal is a prominent feature of the Preserve, and has a long and fascinating history. The name "Company Canal" was probably derived from the Barataria and Lafourche (B & L) Canal Company name. Dr. Thomas Becnel of Nichols State University published an outstanding and highly recommended book (The Barrow Family and the Barataria and Lafourche Canal, 1829-1925) in 1990 that documented the history and construction of the Company Canal. Several prominent men (Robert Barrow, Dr. Walter Brashear, and Judge Charles Derbigny) chartered the B & L Canal Company which was to run from the Mississippi River across Lafourche and Terrebonne Parishes to Bayou Teche. Robert Ruffin Barrow Jr. later became the sole owner of the B & L Canal in 1859 when state legislation ceded the stock and debt of the Company to a new company (B & L Canal Company Number 2) in Houma. The original proposed route of the B & L Canal between Bayou Lafourche and Bayou Terrebonne included the Belanger canal, which extended from Bayou Terrebonne at Bourg toward Lake Long, and the Field Canal, which ran from Lake Field to the backside of Lockport. During the 1830s the B & L Company constructed locks where the B & L Canal crossed Bayou Lafourche. These locks were originally constructed of timbers, but were rebuilt using masonry by 1853. The B & L Canal was completed by 1847. After the Bayou Lafourche dam was constructed in 1904, Robert Barrow Jr. requested permission from the Lafourche Parish Police Jury and the Atchafalaya Basin and Lafourche Basin Levee District to remove the locks to facilitate navigation. He was initially refused, but was eventually allowed to remove the locks later in 1904. The Company Canal was re-dredged in 1905. In 1920 Robert Barrow Jr. blocked the mouth of Bayou Folse at Company Canal to keep water hyacinths from floating into Company Canal, and was threatened with a law suit from the engineering firm of Grant Smith and Company because the blockage prevented them from accessing their headquarters and fuel storage facilities. William Field also played a significant role in the Company Canal near Bayou Lafourche. In 1833 he donated land to the B & L Company on both sides of Bayou Lafourche at Longueville. The land he donated was contiguous to the Field Canal which ran from his property along Bayou Lafourche to Lake Fields. This land was to be used to establish a town, but with the stipulation that the B & L Company must complete a navigable canal from New Orleans to Bayou Terrebonne. After locks were constructed on the east side of the bayou, the settlement became known as Lockport. Lafourche, Barataria, and Canal Steets in Lockport are indicative of the towns’ close ties to the B & L Canal. By the late 1880s, the U.S. Government had become interested in a federally controlled intracoastal waterway across the Louisiana coast. After years of negotiation, Robert Barrow Jr. finally sold the B & L Canal Number 2 to the U.S. Government for $84,000 in 1925, and the Gulf Intracoastal Waterway came into existence. The Waterway followed the Harvey Canal to Larose, Bayou Lafourche to Lockport, and the Company Canal to Bayou Terrebonne. The Corps of Engineers later completed the shortcut from Larose to Bayou Terrebonne near Bourg around 1949, and the route through Bayou Lafourche and Company Canal was abandoned. During the 1930s the juncture of Company Canal and Bayou Lafourche was widened and the canal was relocated about 10 feet to the north so that a narrow strip of land remained between the two canals. The original canal was filled in and lies under the present Canal Street. Reclamation Projects Several reclamation projects in the Lake Fields/Lake Long basin in the early 1900s extended farm land beyond the natural levees along the Bayou Lafourche ridge down into the backswamps and freshwater marshes. These reclamation projects involved the construction of levees and drainage canals to drain the natural marshes, which not only destroyed natural marsh habitats but also altered natural hydrological patterns and resulted in lowered water quality. One of the few successful reclamation projects in coastal Louisiana was an 8,200 acre tract located north and west of the Preserve which is locally called the Raceland Prairie. A portion of this land was part of an Edward Wisner purchase of nearly 1.5 million acres of Louisiana swamp and marshland for twelve cents an acre. The Terrebonne Land Company was formed to reclaim the Raceland Prairie acquisition and to manage it. The reclaimed area was initially farmed, but as soil nutrients were depleted the farms were abandoned; today the reclaimed area is primarily used for raising cattle and residential subdivisions. The Louisiana Rice, Prairie, and Canal Company, whose President was J. M. Dressner of Lockport, also had reclaimed agricultural holdings on the Raceland Prairie. Portions of another land reclamation project encompassed some land within the historic meander line of Lake Fields. A. V. Smith, a native of Michigan, began in 1907 to reclaim an one-mile square mile area southwest of Company Canal that would later be known as Smithport Plantation. The farm was successful for a number of years, but was abandoned during the Depression due to economic reasons, periodic flooding from tropical storms, and levee and drainage failures. The levees and drainage were later restored. This area is currently referred to as the "Emile Toups" or Smithport property. As a result of these reclamation projects, the land was leveed and several drainage canals (Bayou Dumar and Bayou Folse) dug. The immediate area around Lake Long is less developed than around Lake Fields. Drainage Improvements The historic hydrology of the Lake Fields drainage basin was altered beginning in the early 1900s in association with reclamation projects and drainage improvements. The 40-arpent canal was dug to drain the Bayou Lafourche ridge and emptied into Company Canal and bypassed Lake Fields. Other canals such as Cut Off and McMahon Canals were also dug for drainage purposes. A major upper Bayou Folse watershed project took place during the late 1960s and early 1970s by the U.S. Department of Agriculture Soil Conservation Service. The project included clearing and deepening of Bayou Folse and Cut Off Canal to increase flow capacity, levees, pump stations, diversion of water from the 40-arpent canal to Bayou Folse, and other drainage improvements. The Bayou Folse watershed area and flow capacity of the Bayou was substantially increased. As a result, there was a significant increase in upper watershed drainage of more turbid, nutrient-enriched water into Bayou Folse from permitted discharges, cattle pastures, farm lands, and residential areas. However, lower Bayou Folse was shallower and narrower than upper Bayou Folse and was unable to accommodate the increased capacity. Consequently, more of Bayou Folse water flow was diverted through the Commercial Canal into Bayou Dumar and eventually into Lake Fields. A portion of Bayou Folse water also flowed into Lake Fields through breaks along the western bank of lower Bayou Folse. The increased inflow of nutrient-laden, poor quality water from the upper watershed resulted in immediate and long-term adverse impacts on water quality and physical habitats in Lake Fields and surrounding marsh. Water in Lake Fields became more turbid and nutrient enriched and periodic algal blooms and a dramatic decline in submergent aquatic plants occurred. Shoreline erosion also accelerated without the wave-reduction cushion provided by dense growths of submergent and emergent vegetation. In contrast, Lake Long has less inflow of upper watershed water and has clearer water and profuse submergent aquatic vegetation. Restoration Projects There were several permitted restoration projects sponsored by the Commission to address the inflow of degraded water into Lake Fields by facilitating the flow of watershed drainage around rather than through Lake Fields. After a request by the Commission, the Department of Wildlife and Fisheries deployed a dragline in early 1972 to close several cuts into Lake Fields along lower Bayou Folse. The Commission later sponsored a major project to upgrade the west shoreline of Bayou Folse. The first lift was completed in summer of 1976; additional lifts were needed but not completed because of lack of funding. Additional work on the lower Bayou Folse levee took place in early 1981, when the western bank of lower Bayou Folse was reconstructed from sediments dredged from Lake Fields; in addition, a pump station outflow canal to the west of Lake Fields was blocked. In early 1985, lower Bayou Folse was dredged with a Parish dragline to deepen the bayou and increase flow capacity. The dredging of lower Bayou Folse and the restoration of the western bank of Bayou Folse reduced inflow of degraded water into Lake Fields such that water quality improved and submergent vegetation subsequently increased. These improvements, however, were not permanent because channel depths were not increased sufficiently, and the gradual decrease in lower Bayou Folse water depths through accumulation of organic materials and sediments. Lower Bayou Folse was dredged for the second time in 1992 to deepen the waterway; however, this project had less of a positive impact than the 1985 dredging because water depths were not increased as much. Petroleum Related Activities After oil was discovered along the Louisiana coast, numerous canals were dug to facilitate exploration and production and pipelines were laid to transport oil and gas. The majority of these activities took place between 1950 and 1970. Several oil-related canals and pipelines are present within the Preserve, especially south and southeast of Lake Long. Petroleum-related activities have contributed to wetland loss in the Mississippi River Delta. In addition to impacts previously described under the section under transportation canals, oil and gas activities potentially have multiple ecological impacts. Soil subsidence due to depressurization from oil and gas extraction may increase. Pipelines may also destroy marsh or alter surface hydrology. Finally, oil or produced water spills could adversely impact water quality. Bayou Lafourche Modifications Bayou Lafourche was once a major distributary of the Mississippi River; in fact, early explorers in Louisiana considered Bayou Lafourche as the west fork of the Mississippi River. In the early 1800s, Bayou Lafourche was 15-20 feet deep and 200 yards wide and carried roughly 12% (over 40,000 cfs) of the total Mississippi River discharge. As a result, significant freshwater and nutrients were introduced to coastal marshes flanking Bayou Lafourche. Human-induced modifications to Bayou Lafourche began during the War of 1812, when General Andrew Jackson ordered the obstruction of Bayou Lafourche by cutting shoreline trees in various locations in 1814 to prevent British troops from moving up the Bayou to attack New Orleans from the north. These obstructions increased siltation that reduced water depths to 2-3 feet along extended portions of the Bayou and increased flooding during high Mississippi River discharges due to reduced flow capacity. To protect Bayou Lafourche communities from seasonal Mississippi River flooding, the Atchafalaya Basin and Lafourche Basin Levee District constructed a temporary earthern dam across Bayou Lafourche at the Mississippi River in Donaldsonville in 1904. The Levee District never constructed a lock to replace the earthern dam as required by the U.S. Rivers and Harbors Act of 1902. Bayou Lafourche became a stagnant waterway with poor water quality and periodic salt water intrusion penetrating into Central Lafourche; freshwater input into Company Canal and the Preserve was also reduced. The Bayou Lafourche Fresh Water District constructed a pump and siphon at Donaldsonville in 1955. The original capacity of 340 cfs was eventually reduced to 200 cfs over time because of a decline in the Bayou Lafourche channel capacity. The approved Bayou Lafourche Freshwater Introduction project will increase the Mississippi River diversion flow from 200 cfs to 1,100 cfs and enlarge the Bayou Lafourche channel by dredging. Freshwater inflow into Company Canal from Bayou Lafourche is expected to increase. Mississippi River Levees Periodic spring overflows of the Mississippi River occurred in southeast Louisiana which provided freshwater and sediments to nourish adjacent marshes because the Mississippi River levees were small and localized. After the massive 1927 flood, Congress passed the Mississippi River and Tributaries Project, which provided for a continuous large levee from Missouri downstream to New Orleans. The loss of sediments and freshwater through levee construction was and continues to be a significant contributor to wetland loss in coastal Louisiana. Gulf Intracoastal Waterway The modern Gulf Intracoastal Waterway (GIWW) was completed by 1949 at a depth of 12 feet and width of 125 feet. The purpose of the GIWW was to link commerce across the Gulf of Mexico and East Coast. The original GIWW was through Company Canal and Bayou Lafourche, but was later routed further south at Larose. Although the GIWW allows seasonal inflows of freshwater from the Atchafalya River, it also provides an additional corridor for saltwater intrusion from the lower basin into the Preserve. Company Canal Weir A saltwater control structure was constructed in 2003 in Company Canal south of Lake Fields because of the impact of saltwater intrusion via Company Canal on drinking water obtained from Bayou Lafourche. During periods of higher salinities that may occur during periods of low rainfall and/or low Atchafalaya River discharges, the control structure may be closed to prevent upstream salt water intrusion. Unfortunately, the weir will be moved in 2013 to Bayou Lafourche north of Company Canal. The weir was moved to Bayou Lafourche north of Company Canal in 2013. Houma Navigation Canal The Houma Navigational Channel was built in 1962 at a depth of 15 feet and width of 150 feet to link the GIWW in Houma with the Gulf of Mexico. The GIWW provided a massive corridor for saltwater intrusion into the upper Terrebonne Bay estuary, including the Preserve. Saltwater intrusion up the Navigational Channel and eventually into Bayou Lafourche was linked to a drinking water crisis in Bayou Lafourche in November 2000. Future Projects There are several proposed hurricane protection or coastal restoration projects in the vicinity of the Preserve that may directly or indirectly impact the Preserve ecosystem in the future; these include the Morganza to the Gulf hurricane protection levee system, Third Delta Conveyance Channel, and north Lafourche hurricane protection projects. 
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