Morganza Spillway/Floodway and Old River Control Structure - Louisiana Environmental Action Network Louisiana Environmental Action Network Home » Our Work » Uncategorized » Morganza Spillway/Floodway and Old River Control Structure Morganza Spillway/Floodway and Old River Control Structure Click to share on Pinterest (Opens in new window) The Morganza Spillway east of Melville, Louisiana, was opened on May 14, 2011, to divert Mississippi River water into the Atchafalaya Basin. The diversion of Mississippi River water was necessary to lower the Mississippi River flood stage and reduce pressure on the levee system along the lower portions of the river. The opening of the Morganza Spillway was initiated in order to protect Baton Rouge and New Orleans from being flooded by the over topping of their levees and reduce the possibility of levee failure.

Diverting Mississippi River water into the Atchafalaya River and Atchafalaya Basin Update and Ground Patrol for Louisiana Environmental Action Network and Lower Mississippi Riverkeeper by Wilma Subra May 20, 2011 Morganza Spillway Structure The Morganza Spillway east of Melville, Louisiana, was opened on May 14, 2011, to divert Mississippi River water into the Atchafalaya Basin. The diversion of Mississippi River water was necessary to lower the Mississippi River flood stage and reduce pressure on the levee system along the lower portions of the river. The opening of the Morganza Spillway was initiated in order to protect Baton Rouge and New Orleans from being flooded by the over topping of their levees and reduce the possibility of levee failure. On May 22, 2011, 17 of the 125 bays in the Morganza Spillway were open and allowing Mississippi River water to flow into the Atchafalaya Basin.

As the Mississippi River water passed through the Spillway, the water was roaring, foaming, creating rapids and dispersing water into the air on the Atchafalaya Basin side of the spillway. A crane mounted on a barge was rapidly placing large sand bags along the Mississippi River side of the levee, adjacent to the Spillway structure, to stabilize and raise the elevation of the levee. The water on the MIssissippi River side of the Spillway structure was near the top of the levees on either side of the Spillway. Large sand bags had been placed on top of the levee system to raise the level of protection where the Mississippi River levee system joins the Morganza spillway levees. Mississippi River water flowing through the Morganza Spillway. The Morganza Spillway down stream from the Morganza Spillway structure was flooded with diverted Mississippi River water and the water was moving down the spillway and flooding agricultural fields, homes and businesses. The harvesting of the wheat crop in the Morganza Spillway area was completed just prior to the opening the spillway.

The corn, soybean, rice and sugarcane crops within the Morganza Spillway have been destroyed by the flood waters. Meanwhile, the crops outside of the Morganza Spillway are desperate for rain. Security in the area of the Morganza Spillway was very tight and access was very limited as compared to two weeks earlier when access was unlimited. Sheriff deputies and National Guard troops guarded the spillway structure and blocked the access roads in the area. Traffic was not allowed to stop or park within five miles of the spillway structure. Old River Control Complex The Old River Control Complex, northeast of Simmesport, Louisiana, diverts 30% of the Mississippi River flow into the Atchafalaya River on an ongoing basis. The Old River Control Complex consist of four structures that divert Mississippi River water into the Atchafalaya River: Auxiliary Structure, Low Sill Structure, Over Bank Structure, and the Sidney A. Murray, Jr. Hydroelectric Station. The Auxiliary Structure had all six gates open and the Low Sill Structure had 15 bays opened on May 22, 2011.

The two structures were responsible for the largest portion of flow of Mississippi River water into the Atchafalaya River. The Over Bank structure had a small rate of flow. The Hydroelectric Station was discharging water which had been directed through the plant to generate electricity. The water roaring through the Auxiliary Structure and Low Sill Structure produced whirlpools, large waves, rapids, water dispersed into the air and very dangerous condition. Egrets, pelicans and blue herons feasted in the churning waters that exited all four structures. Fishermen in boats and along the banks were no longer present due to the dangerous situations associated with the fast moving and very large quantities of water moving through the control structures. Mississippi River water flowing through the Low Sill Structure at the Old River Control Complex. The Auxiliary Structure is visible in the background. Just down river from the Old River Control Complex, the Old River Locks were closed to boat traffic due to the high water stage. Tug boats with barges loaded with boulders, rocks, and gravel were anchored in the locks staging area. They were on standby in cast of emergency situations and needs to stabilize the banks at the Old River Control Complex.

Just upriver from the Old River Control Complex, backwater flooding from the overflow channel and Atchafalaya River inundated an oil well production field. Pump jacks were submerged in flood waters throughout the field. Oil well pump jacks submerged in water just upriver from the Old River Control Complex. Further upriver from the Old River Control Complex, hundreds of deer, displaced by the floodwaters, grazed in a partially submerged soybean field. A corn field adjacent to the soybean field offered no attract to the deer. Deer grazing in partially submerged soy bean field upriver from the Old River Control Complex. Security in the area of the Old River Control Complex, as well as upstream and downstream along the Mississippi River was extremely tight. Two weeks ago one could park and walk on the structures as well as walk on the banks of the structures. Current access is limited to only driving through the area. No parking, no stopping and no foot access. Atchafalaya Basin and Atchafalaya River The Morganza Spillway directs Mississippi River water into the Atchafalaya Basin. The Old River Control Complex directs Mississippi River water into the Atchafalaya River.

As a result of the Mississippi River water being directed into the Atchafalaya River and Basin, homes and roads in the communities of Simmesport and Melville are under water along the edge of the Atchafalaya River. Homes outside of the ring levees in each of the communities are also flooded. The basin is filling with water. The Atchafalaya River is fast moving with waves, eddies and rapids on the river. Homes submerged in Atchafalaya River water in Simmesport. In the community of Krotz Springs on the Atchafalaya River and in the Atchafalaya Basin, flooding from the Morganza Spillway waters has inundated the basin on the eastern side of the Atchafalaya River. Along the Atchafalaya River, roads and buildings, not protected by levees, are under water. On the southern side of the town, HESCO Baskets and bags have been used to construct levees to protect homes in areas that lacked levees. HESCO Baskets have also been used to form a levee on the southern perimeter of the Krotz Springs Refinery.

Pipe line stations in the Krotz Springs area are surrounded by sandbags and HESCO baskets. Krotz Springs Refinery with HESCO Baskets forming a protective levee. North of Krotz Springs, on the western side of the Atchafalaya River, sand boil areas are present on the dry side of the levee system. The sand boil areas indicate seepage of water under the levee system. During the severe drought conditions currently present throughout central and southern Louisiana, the presence of the sand boils are very east to detect. Sand boil north of Krotz Springs on the western side of the Atchafalaya River. Security and Monitoring Security throughout the areas along the levee systems of the Mississippi and Atchafalaya rivers, spillways and control structures are very tight. All access roads to the levee systems are blocked and manned. Access to the Morganza Spillway and the Old River Control Complex Structures are restricted to auto access with no stopping, parking or foot access. Deputies Sheriff personnel and National Guard troops are very present in each and every community. One cannot move around the communities without being observed by the troops.

Inspectors are continuously monitoring the levee systems for leaks, sand boils and levee failures, while measuring the height of the water and the levees. Filed Under: Uncategorized Related Terms: riverkeeper Subscribe To Our E-Alerts (blog) Enter your email address to get our e-alerts by email. E-Mail Address Morganza Spillway/Floodway and Old River Control Structure - Lower Mississippi Riverkeeper - Waterkeeper Alliance Member Morganza Spillway/Floodway and Old River Control Structure Posted on Diverting Mississippi River water into the Atchafalaya River and Atchafalaya Basin Update and Ground Patrol for Louisiana Environmental Action Network and Lower Mississippi Riverkeeper by Wilma Subra May 20, 2011 Morganza Spillway Structure The Morganza Spillway east of Melville, Louisiana, was opened on May 14, 2011, to divert Mississippi River water into the Atchafalaya Basin. The diversion of Mississippi River water was necessary to lower the Mississippi River flood stage and reduce pressure on the levee system along the lower portions of the river.

The opening of the Morganza Spillway was initiated in order to protect Baton Rouge and New Orleans from being flooded by the over topping of their levees and reduce the possibility of levee failure. On May 22, 2011, 17 of the 125 bays in the Morganza Spillway were open and allowing Mississippi River water to flow into the Atchafalaya Basin. As the Mississippi River water passed through the Spillway, the water was roaring, foaming, creating rapids and dispersing water into the air on the Atchafalaya Basin side of the spillway. A crane mounted on a barge was rapidly placing large sand bags along the Mississippi River side of the levee, adjacent to the Spillway structure, to stabilize and raise the elevation of the levee. The water on the MIssissippi River side of the Spillway structure was near the top of the levees on either side of the Spillway. Large sand bags had been placed on top of the levee system to raise the level of protection where the Mississippi River levee system joins the Morganza spillway levees. Mississippi River water flowing through the Morganza Spillway.

The Morganza Spillway down stream from the Morganza Spillway structure was flooded with diverted Mississippi River water and the water was moving down the spillway and flooding agricultural fields, homes and businesses. The harvesting of the wheat crop in the Morganza Spillway area was completed just prior to the opening the spillway. The corn, soybean, rice and sugarcane crops within the Morganza Spillway have been destroyed by the flood waters. Meanwhile, the crops outside of the Morganza Spillway are desperate for rain. Security in the area of the Morganza Spillway was very tight and access was very limited as compared to two weeks earlier when access was unlimited. Sheriff deputies and National Guard troops guarded the spillway structure and blocked the access roads in the area. Traffic was not allowed to stop or park within five miles of the spillway structure. Old River Control Complex The Old River Control Complex, northeast of Simmesport, Louisiana, diverts 30% of the Mississippi River flow into the Atchafalaya River on an ongoing basis.

The Old River Control Complex consist of four structures that divert Mississippi River water into the Atchafalaya River: Auxiliary Structure, Low Sill Structure, Over Bank Structure, and the Sidney A. Murray, Jr. Hydroelectric Station. The Auxiliary Structure had all six gates open and the Low Sill Structure had 15 bays opened on May 22, 2011. The two structures were responsible for the largest portion of flow of Mississippi River water into the Atchafalaya River. The Over Bank structure had a small rate of flow. The Hydroelectric Station was discharging water which had been directed through the plant to generate electricity. The water roaring through the Auxiliary Structure and Low Sill Structure produced whirlpools, large waves, rapids, water dispersed into the air and very dangerous condition. Egrets, pelicans and blue herons feasted in the churning waters that exited all four structures. Fishermen in boats and along the banks were no longer present due to the dangerous situations associated with the fast moving and very large quantities of water moving through the control structures. Mississippi River water flowing through the Low Sill Structure at the Old River Control Complex. The Auxiliary Structure is visible in the background.

Just down river from the Old River Control Complex, the Old River Locks were closed to boat traffic due to the high water stage. Tug boats with barges loaded with boulders, rocks, and gravel were anchored in the locks staging area. They were on standby in cast of emergency situations and needs to stabilize the banks at the Old River Control Complex. Just upriver from the Old River Control Complex, backwater flooding from the overflow channel and Atchafalaya River inundated an oil well production field. Pump jacks were submerged in flood waters throughout the field. Oil well pump jacks submerged in water just upriver from the Old River Control Complex. Further upriver from the Old River Control Complex, hundreds of deer, displaced by the floodwaters, grazed in a partially submerged soybean field. A corn field adjacent to the soybean field offered no attract to the deer. Deer grazing in partially submerged soy bean field upriver from the Old River Control Complex. Security in the area of the Old River Control Complex, as well as upstream and downstream along the Mississippi River was extremely tight. Two weeks ago one could park and walk on the structures as well as walk on the banks of the structures.

Current access is limited to only driving through the area. No parking, no stopping and no foot access. Atchafalaya Basin and Atchafalaya River The Morganza Spillway directs Mississippi River water into the Atchafalaya Basin. The Old River Control Complex directs Mississippi River water into the Atchafalaya River. As a result of the Mississippi River water being directed into the Atchafalaya River and Basin, homes and roads in the communities of Simmesport and Melville are under water along the edge of the Atchafalaya River. Homes outside of the ring levees in each of the communities are also flooded. The basin is filling with water. The Atchafalaya River is fast moving with waves, eddies and rapids on the river. Homes submerged in Atchafalaya River water in Simmesport. In the community of Krotz Springs on the Atchafalaya River and in the Atchafalaya Basin, flooding from the Morganza Spillway waters has inundated the basin on the eastern side of the Atchafalaya River.

Along the Atchafalaya River, roads and buildings, not protected by levees, are under water. On the southern side of the town, HESCO Baskets and bags have been used to construct levees to protect homes in areas that lacked levees. HESCO Baskets have also been used to form a levee on the southern perimeter of the Krotz Springs Refinery. Pipe line stations in the Krotz Springs area are surrounded by sandbags and HESCO baskets. Krotz Springs Refinery with HESCO Baskets forming a protective levee. North of Krotz Springs, on the western side of the Atchafalaya River, sand boil areas are present on the dry side of the levee system. The sand boil areas indicate seepage of water under the levee system. During the severe drought conditions currently present throughout central and southern Louisiana, the presence of the sand boils are very east to detect. Sand boil north of Krotz Springs on the western side of the Atchafalaya River. Security and Monitoring Security throughout the areas along the levee systems of the Mississippi and Atchafalaya rivers, spillways and control structures are very tight.

All access roads to the levee systems are blocked and manned. Access to the Morganza Spillway and the Old River Control Complex Structures are restricted to auto access with no stopping, parking or foot access. Deputies Sheriff personnel and National Guard troops are very present in each and every community. One cannot move around the communities without being observed by the troops. Inspectors are continuously monitoring the levee systems for leaks, sand boils and levee failures, while measuring the height of the water and the levees. Related Posts: Morganza Spillway | Military Wiki | Fandom powered by Wikia Edit The Great Mississippi Flood of 1927 was the most destructive river flood in the history of the United States, [6] in large part due to the Mississippi River swelling to 80 miles (130 km) wide in spots.

[7] To prevent a repeat of the Great Flood of 1927, and better control river flooding in general, Congress passed the Flood Control Act of 1928 to authorize the United States Army Corps of Engineers to build the Bonnet Carre Spillway (located 33 miles (53 km) above New Orleans and completed in 1931), [8] the Birds Point floodway in Missouri, and the Morganza Floodway as part of the 1928 Mississippi River and Tributaries Project . [7] One of the 125 gates on the tail bay side of the Morganza Floodway. Construction of the levees that make up part of the Morganza Spillway began in the late 1930s. The Morganza Control Structure portion of the project was completed in 1954 [7] and subsequently became incorporated into the Mississippi River Commission 's 1956 project design flood , [9] which added the Old River Control Structure (ORCS) in 1963 to the protections used to prevent Mississippi River flood.

[10] The Flood Control Act of 1965 provided further regulation over the Morganza Spillway's role in Mississippi River flood prevention. A concrete pit called a stilling basin was added at the Morganza Spillway in 1977 "to provide erosion protection after the velocity of water pouring through the open bays during a 1973 flood caused severe scouring of the land behind the bays." [11] Design and construction Edit The Morganza Spillway, a 4,159-foot (1,268 m) controlled spillway using a set of flood gates to control the volume of water entering the Morganza Floodway from the Mississippi River, consists of a concrete weir , two sluice gates, seventeen scour indicators, and 125 gated openings which can allow up to 600,000 cubic feet per second (17,000 cubic metres per second) of water to be diverted from the Mississippi River into the Atchafalaya Basin during major floods. The project was completed in 1954. A highway ( Louisiana Route 1 ) and the Kansas City Southern Railway cross the structure.

The Corps of Engineers maintains the structures and, in times of flood, monitors their piers for scouring and stability. To lift and lower the flood gates, the Corps of Engineers maneuvers a movable crane along the spillway to the particular opening. Operation during floods Edit The land on both sides of the Morganza Control Structure is above normal river water levels, and usually dry. In order for water to reach the spillway, the Mississippi must first rise well above its flood stage , overtopping its banks. The Corps of Engineers considers opening the Morganza Spillway when the flow of the Mississippi at Red River Landing, Louisiana , [12] [13] is greater than 1,500,000 cu ft/s (42,000 m3/s) and rising. [1] A diagram that depicts river flows flow through the Morganza Spillway to the Red and Atcahafalaya Rivers associated with a project design flood , which is the hypothetical "maximum probable" flood of the Mississippi River, as estimated by the Corps of Engineers. The water channel flow rates are listed in thousands of cubic feet per second.

Water from the Mississippi is normally diverted into the Atchafalaya Basin at only one place, the Old River Control Structure (ORCS), in use since 1963, where floodgates are routinely used to redirect the Mississippi's flow into the Atchafalaya River such that the volume of the two rivers is split 70%/30%, respectively, as measured at the latitude of Red River Landing . During the 1973 Mississippi flood, the ORCS was being damaged due to high flow rates, leading to the opening of the Morganza Spillway to help relieve this pressure. Subsequently, the nearby Old River Control Auxiliary Structure (ORCAS) was constructed, adding additional floodgates for use during major floods. The Morganza Spillway, about 30 miles (48 km) downriver from ORCS and ORCAS, is designed for emergency use to divert additional water from the Mississippi River into the Morganza floodway, which merges downstream with the Atchafalaya floodway before entering the Gulf.

Diversion of water from the Mississippi's main channel has the effect of lowering water level in the Mississippi downstream of the spillway, helping to relieve stress on levees and other flood control structures both upstream and down. Besides controlling flooding in a given event, the system is also designed to prevent the Mississippi River from permanently altering course down the Atchafalaya River, bypassing Baton Rouge and New Orleans. [1] [2] [3] [4] Water that passes the Morganza Spillway first enters the Morganza Floodway, which extends from the spillway at the Mississippi River south to the East Atchafalaya River levee. The floodway, 20 miles (32 km) long and 5 miles (8.0 km) wide, includes a stilling basin, an approach channel, an outlet channel, and two guide levees . [1] From there, diverted water enters the Atchafalaya River Basin Floodway near Krotz Springs, Louisiana , [1] and continues to the Gulf of Mexico.

In an extreme flood event, a major release of water from the Morganza Spillway into the Morganza Floodway and Atchafalaya Basin inundates not only the floodways themselves (between their levees), but extensive additional areas of southern Louisiana throughout the Atchafalaya Basin . In such an event, the water level of the Mississippi, high enough to overtop the Spillway, would already be flooding some areas in the Basin downstream of the spillway, due to increased flow through the ORCS and the ORCAS, as well as possible overtopping of levees near the spillway. [14] This flooding, plus any additional water from a Morganza Spillway release, together determine the total extent of flooding throughout the Atchafalaya Basin during a major Mississippi River flood. At risk in the Atchafalaya Basin are Morgan City (population 13,500), various smaller populated places, many farms, thousands of oil and gas wells, and considerable swampland. Inhabitants know that the region is a natural floodplain , and the Corps of Engineers issues written notices annually to all interests reminding them of the possibility that it might open the spillway and flood the area.

Any decision to open the spillway must be carefully planned to give ample warning and protect life and property. Part of that planning process includes the Corps' preparation of maps known as "inundation scenarios" so that interested parties can discuss how much water, if any, should be allowed through the spillway. [1] [15] [16] [17] [18] [19] [20] [21] [ citation needed ] [22] During both moderate and severe floods of the Mississippi, the Bonnet Carré Spillway can also be opened to help protect New Orleans, many parts of which are below sea level. The Bonnet Carré Spillway, built after the Great Mississippi Flood of 1927 , is located well downstream of Morganza, where the Mississippi River approaches Lake Pontchartrain near New Orleans. The Corps uses Bonnet Carré to divert floodwaters into the lake in order to protect the levees near New Orleans.

Integrity of the Morganza Spillway, the Old River Control Structure, and nearby levees is essential to prevent the Mississippi from diverting its main channel into the Atchafalaya Basin; see "Risk of major course change in the Lower Mississippi River" for further discussion. Flood events and the Morganza Spillway Since its completion in 1954, the Morganza Spillway has been opened twice (in 1973 and 2011), and considered for opening during four other major floods of the Lower Mississippi River. First opening of gates (1973) Edit On April 17, 1973, in order to lower the water level of the Mississippi River and relieve pressure on the Old River Control Structure, the Corps of Engineers opened 42 of the 125 steel gates of the Morganza Spillway for the first time since its completion, allowing about half of its maximum designed flowrate to pass from the Mississippi into the Atchafalaya Basin. The spillway received minor scouring and slight damage to the stilling basin, and substantial flooding occurred in the Atchafalaya Basin.

After the 1973 flood, the structure was restored to its original condition. [1] [3] [23] [24] Gates left closed in floods of 1983, 1993, 1997, and 2008 Edit The issue of opening the gates to keep the Mississippi in its current place was next raised in May 1983. [25] Although the gates were not opened, Louisiana Highway 1 running across the spillway was closed, and the Corps of Engineers built a 12-foot (3.7 m) ring dike and put a blanket of earth across a section of the spillway to contain water pouring underneath it. [26] During the Great Mississippi and Missouri Rivers Flood in 1993 , officials decided to leave the gates of the Morganza Floodway closed. [27] In March 1997, the river water flow at Baton Rouge reached 10,600,000 US gal (1,420,000 cu ft) (40,000 m3) per second.

[28] However, the flow rate never reached the threshold of 11,200,000 US gal (1,500,000 cu ft) (42,000 m3) per second for opening Morganza, [28] and residents of Sicily Island, Louisiana , became angry that the spillway was not opened to prevent flooding in their homes. [29] [30] [31] In March–April 2008, officials considered but declined to open the spillway gates. [24] [32] [33] While the spillway gates remained closed then, flooding still occurred in part of the Morganza floodway when the Mississippi River crested higher than levees near the spillway. Local residents and National Guard troops attempted to add height to the permanent levee by building a supplemental sandbag levee on top of it. However, additional rainfall raised the flood crest higher than even the supplemental sandbags, sending floodwaters over these levees into 3,000 acres (1,200 ha) of cropland located within the floodway.

[14] Second opening of gates (2011) Anticipated inundation from Scenario 1 Anticipated inundation from Scenario 1a Anticipated inundation from Scenario 2 Anticipated inundation from Scenario 3 The 2011 Mississippi River floods began to become serious in April. In response, the Corp first analyzed the flooding, and then opened the spillway in a controlled manner. The Corps studied four flooding scenarios, all of which assumed the Bonnet Carré Spillway would be concurrently operating at full capacity (100%). Scenario 1: Open the Morganza Spillway to half (50%) of its maximum capacity, which would divert 300,000 cubic feet per second (8,500 m3/s) of water. Scenario 1a: Open the Morganza Spillway to one-quarter (25%) of its maximum capacity, which would divert 150,000 cubic feet per second (4,200 m3/s) of water.

Scenario 2: Do not open the Morganza Spillway, and keep the Old River Control Structure at its routine operating level of only 30% of the Mississippi's flow; no additional water would be diverted Scenario 3: Do not open the Morganza Spillway, and open the ORCS somewhat more, which would divert an extra 150,000 cubic feet per second (4,200 m3/s) of water. Following this analysis, which showed that extensive flooding was expected in the Atchafalaya Basin regardless of the choice made regarding the Morganza Spillway, the Corps decided to start the 2011 diversion by opening the spillway a bit less than described in scenario 1a (21%, not 25%) [35] The Governor of Louisiana, Bobby Jindal , had meanwhile sent a letter on May 4, 2011, to Robert Gates , the United States Secretary of Defense , requesting that the National Guard be deployed under Title 32 of the United States Code status to respond to record water levels in Louisiana, where there was "a significant probability that the U.S.

Army Corps of Engineers [would] open the Morganza Spillway for the first time since 1973." [36] The second opening of the Morganza Spillway began with the lifting of a single floodgate on May 14, 2011. Diversion of 125,000 cubic feet per second (3,500 m3/s) of water from the Mississippi River to the Atchafalaya Basin was planned during this event, with the structure operating at about 21% of its capacity. This diversion was deemed necessary to protect levees and prevent major flooding in Baton Rouge and New Orleans, with the tradeoff of creating possibly severe flooding in the Atchafalaya Basin. [1] [37] By May 18, 2011, a total of 17 gates (the largest number for the 2011 event) had been opened by the Corps of Engineers. The Corps estimated the flow rate at 114,000 cu ft/s (3,200 m3/s). However, on May 25, new estimates from the U.S.

Geologic Survey (USGS) described a much higher rate of 172,000 cu ft/s (4,900 m3/s), resulting in the closure of 3 bays by May 26, and additional closures by May 29, bringing the total to 11 bays with an estimated diversion rate of 120,000 cu ft/s (3,400 m3/s). [38] [39] The Corps continued to evaluate the flow and close additional bays as appropriate. By June 6, the number of open gates had been reduced to seven, [40] and by June 8, only two gates were still open. [39] All bays were closed on July 7, 2011.

The Corps had estimated that it would take opening one-fourth of the spillway’s 125 bays — or 31 bays — to control the flow of the river through Baton Rouge in response to a forecast crest of 45 feet (14 m) anticipated on Tuesday, May 17, 2011, which must remain below 1,500,000 cu ft/s (42,000 m3/s) of water per second through Baton Rouge to ensure the integrity of the levee system. [41] Since Morganza never operated above 172,000 cu ft/s (4,900 m3/s), the flooding in the Atchafalaya Basin was considerably lower than had been anticipated during the initial estimates of 300,000 cu ft/s (8,500 m3/s). [38] By May 29, the Corps had also opened 330 of the 350 bays of the Bonnet Carré Spillway located near New Orleans.

[39] Aerial photograph of the first bay opening on the Morganza Floodway on 14 May 2011. The Mississippi River is in the upper left background, and the Atchafalaya Floodway to the right. Water travel time down the Morganza Floodway after the May 14, 2011 opening. Natural-colour satellite image of the Floodway on May 15, 2011. False colour satellite image of the Floodway on May 15, 2011. For other images of the Morganza Control Structure in operation during the 2011 flood, see the U.S. Army Corps of Engineers Flickr page . See also Morganza Spillway Opened - YouTube Morganza Spillway Opened Want to watch this again later? Sign in to add this video to a playlist. Need to report the video? Sign in to report inappropriate content. Rating is available when the video has been rented. This feature is not available right now. Please try again later. Uploaded on May 15, 2011 Courtesy: U.S.

Army Corps of Engineers From Wikipedia, the free encyclopedia The Morganza Spillway is a flood-control structure in Louisiana between the Mississippi River and the Morganza Floodway, which leads to the Atchafalaya Basin and the Atchafalaya River in south-central Louisiana. The structure, located along the western bank of the Mississippi River at river mile 280, about three miles northwest of Morganza and 151 river miles upstream from Norco in Pointe Coupee Parish, is operated by the U.S. Army Corps of Engineers. Its purpose is to divert water from the Mississippi River during major flood events by flooding the Atchafalaya River and the Atchafalaya Basin (Atchafalaya Swamp). The spillway and adjacent levees also help prevent the Mississippi from changing its present course through the major port cities of Baton Rouge and New Orleans, Louisiana, to a course directly down the Atchafalaya to the Gulf of Mexico. The Morganza spillway has been opened only twice, in 1973 and 2011.

The spillway's thousands of acres of forest and farmland are home to the Louisiana black bear (Ursus americanus luteolus), which has been on the United States Fish and Wildlife Service threatened list since 1992. The Great Mississippi Flood of 1927 was the most destructive river flood in the history of the United States, in large part due to the Mississippi River swelling to 80 miles wide in spots. To provide protection against river flood and prevent a repeat of the Great Flood of 1927, Congress passed the Flood Control Act of 1928 to authorize the United States Army Corps of Engineers to build the Bonnet Carre Spillway (located 33 miles above New Orleans and completed in 1931), the Birds Point floodway in Missouri, and the the Morganza Floodway as part of the 1928 Mississippi River and Tributaries Project. The Morganza control structure portion of the project was completed in 1954 and subsequently became incorporated into the Mississippi River Commission's 1956 Project Design Flood, which added the Old River Control Structure in 1963 to the protections used to prevent Mississippi River flood.

The Flood Control Act of 1965 provided further regulation over the Morganza Spillway's role in Mississippi River flood prevention. A concrete pit called a stilling basin was added at the Morganza Spillway in 1977 "to provide erosion protection after the velocity of water pouring through the open bays during a 1973 flood caused severe scouring, or gouging out, of the land behind the bays." Click to subscribe! The most viewed aviation channel on YouTube. Category Morganza Floodway opens to divert Mississippi River away from Baton Rouge, New Orleans | NOLA.com Morganza Floodway opens to divert Mississippi River away from Baton Rouge, New Orleans comments In a historic action designed to minimize the risk of catastrophic flooding in Baton Rouge and New Orleans, the Army Corps of Engineers has begun opening the Morganza Floodway to divert water from the rain-swollen Mississippi River into the Atchafalaya basin. The second-ever opening of the nearly 60-year-old structure 186 miles upriver of New Orleans began at 3 p.m.

sharp, when a crane lifted a gate covering one of the spillway structure’s 125 bays, releasing a gusher of about 10,000 cubic feet of water per second into the floodway. A live video feed of the procedure is being streamed online by the corps. More of the 28-foot-wide bays will be opened in the coming days to gradually increase the flow rate to about 125,000 cubic feet per second, corps officials said. About 25,000 people and 11,000 structures are in harm’s way, as up to 25 feet of flooding is expected in a 3,000 square-mile area of Cajun country stretching from Melville to Morgan City. The water is expected to pass below Interstate 10 in a day and reach Morgan City in three days, said Col. Ed Fleming, commander of the corps' New Orleans district. The spillway opening had been a foregone conclusion for the past week, but the corps reduced the amount of water it planed to divert into the spillway by nearly 60 percent to about 125,000 cubic feet per second.

That’s less than a quarter of the control structure’s capacity of 600 cubic feet per second, which could be a rare bit of good news for people with property in the spillway. View full size Army Corps of Engineers mapThe Army Corps of Engineers' estimated inundation map above shows the parishes that will be affected by the opening of the Morganza Floodway. Sheriff’s deputies and members of the Louisiana National Guard have been going door-to-door to alert people of the pending flooding. The decision to open the spillway was triggered when the river’s flow rate reached 1.5 million cubic feet per second and rising at Red River Landing across from the State Penetentiary at Angola. Those conditions occurred Friday afternoon, prompting corps officials to announce the spillway would be opened within 24 hours. The Morganza control structure was completed in 1954 as part of the corps’ sweeping flood-protection upgrades to prevent a repeat of the Great Flood of 1927.

The only other time the spillway opened was in 1973 to relieve pressure on the Old River Control Structure, a critical barrier 35 miles upriver that prevents the Mississippi from its natural tendency to shift course to the Atchafalaya Basin, a steeper shortcut to the Gulf of Mexico. Such a shift would have a catastrophic economic impact on the ports in New Orleans and Baton Rouge. Opening the Morganza Spillway and the Bonnet Carre Spillway near Norco is designed to avoid a doomsday scenario in which New Orleans could be swamped with 20 feet of water, far worse than the flooding during Hurricane Katrina in 2005. Saturday marked the first time in history that all three floodways built by corps after 1927 flood -- the Morganza Floodway, the Bonnet Carre Spillway and the Birds Point floodway in Missouri -- have been in operation at the same time, according to the corps. oceans of trouble Flooding: Morganza Spillway May Soon be Opened Flooding: Morganza Spillway May Soon be Opened By By Alex Sosnowski, Expert Senior Meteorologist.

May 14, 2011, 11:59:46 PM EDT According to Louisiana Governor Bobby Jindal, in a recent news conference, the Morganza Spillway will be opened as the slow-moving natural disaster along the Mississippi River continues. The move would impact an additional 25,000 people, agricultural and wildlife areas with flooding. The Morganza Spillway, completed in 1954, is a flood control option that can be used when the flow of the Mississippi River at Red River Landing, reaches a certain threshold. That point was getting close Friday morning with the water near 1.48 million cubic feet per second. According to the U.S. Army Corps of Engineers , the trigger for opening the spillway is 1.50 million cubic feet per second and rising and is forecast by National Weather Service hydrologists to be reached this weekend. Meanwhile, in the path of the spillway waters, crews were busy shoring up levees around multiple communities. A secondary levee was being constructed around Krotz Springs and a refinery located there. The crews and residents were hoping for a few extra days before the spillway is opened, slowly releasing water from the Mississippi.

Levels along the lower Mississippi is surpassing marks set back in 1973, 1937 and 1927. If the Morganza Spillway is activated an area nearly the size of Connecticut will be flooded in central and southern Louisiana. However, the move would take pressure off levees around nearby Baton Rouge and the downstream port of New Orleans , lowering flow rates and river levels in those and other areas. The Bonnet Carre spillway was partially opened on Monday to lower river levels and flow rates around New Orleans . The move at Bonnet Carre is expected barely to keep the river below the tops of the 20-foot levees. Late this week, the Army Corps of Engineers opened more of the Bonnet Carre's bays in an attempt to allow shipping to continue for a while longer along the river. If the flow becomes too strong on Old Man River, boats cannot steer. A record crest of 47.5 feet is forecast on May 22 at Baton Rouge , but this does not account for the opening of the Morganza Spillway. The Morganza Spillway directs some of the flow from the Mississippi River into the Atchafalaya Basin.

If opened, water would slowly flood the parishes of St. Landry, St. Martin, Iberia, Morgan City and St. Mary with up to 25 feet of water. This map shows the approximate areas that would be flooded (bright colored areas). A larger view of this map is available at the U.S. Army Corps of Engineers Website . Direct and indirect flooding (water backing up into bayous and lakes) could affect approximately 25,000 people and agricultural areas. Some communities within this zone are protected by ring levees. Fortunately, since the flooding process along the Mississippi is very slow, it is giving people time to move valuables, take preventative measures and simply get out of the way in case evacuation orders are given. The river flooding is not like a flash flood or tsunami, which can overwhelm communities in seconds and minutes. Unfortunately, the agonizingly drawn-out nature of the flooding will have many areas under water and levees holding back the water for weeks. The battle and worrying will go beyond the point of crest and the the patrol for boils and breaches will continue for weeks. Boils are caused when water travels under a levee and comes to the surface on the side that is being protected.

If not dealt with in a timely manner, the boils can continue to undermine a levee, leading to failure. The levees along the lower Mississippi River are deemed the strongest in the nation and are largely constructed of nearly impenetrable clay. Some rain and locally drenching thunderstorms will swing through the lower Mississippi Valley and the Delta region into early Saturday. Not enough rain is forecast to fall over a large enough area to impact the major river flooding. Enough rain will fall at the local level to cause urban and flash flooding incidents in parts of the Midwest and the South over the next five days. The Control of Nature – Morganza Spillway – LSU Law Center: Climate Change Law and Policy Project • 1 Comment John McPhee has written a fascinating history of the River Control Structure at Morganza. While it is not clear that the Mississippi still wants to go down the Atchafalaya, losing the River Control Structure in a flood would still be a catastrophe that could rival Katrina. “Three hundred miles up the Mississippi River from its mouth—many parishes above New Orleans and well north of Baton Rouge—a navigation lock in the Mississippi’s right bank allows ships to drop out of the river.

In evident defiance of nature, they descend as much as thirty-three feet, then go off to the west or south. This, to say the least, bespeaks a rare relationship between a river and adjacent terrain—any river, anywhere, let alone the third-ranking river on earth.” Mississippi River 2011 125,000 cubic feet per second - Aaron Neville - Louisiana 1927 1080HD - YouTube Mississippi River 2011 125,000 cubic feet per second - Aaron Neville - Louisiana 1927 1080HD Want to watch this again later? Sign in to add this video to a playlist. Need to report the video? Sign in to report inappropriate content. Rating is available when the video has been rented. This feature is not available right now. Please try again later. Uploaded on May 16, 2011 The Morganza Spillway is a flood-control structure in Louisiana along the western bank of the Mississippi River at river mile 280, about three miles northeast of Morganza in Pointe Coupee Parish.

The spillway stands between the Mississippi and the Morganza Floodway, which leads to the Atchafalaya Basin and the Atchafalaya River in south-central Louisiana. Its purpose is to divert water from the Mississippi River during major flood events by flooding the Atchafalaya Basin, including the Atchafalaya River and the Atchafalaya Swamp. The spillway and adjacent levees also help prevent the Mississippi from changing its present course through the major port cities of Baton Rouge and New Orleans, Louisiana, to a new course directly down the Atchafalaya to the Gulf of Mexico. The Morganza Spillway is operated by the U.S. Army Corps of Engineers. Its gates have been opened only twice, during major Mississippi River floods in 1973 and 2011. In May 2011, during the 2011 Mississippi River floods, the second opening of the Morganza Spillway began with the lifting of a single floodgate on May 14.

Diversion of 125,000 cubic feet per second (3,500 m3/s) of water from the Mississippi River to the Atchafalaya Basin is planned during this event, with the structure operating at about 21% of its capacity. This diversion was deemed necessary to protect levees and prevent major flooding in Baton Rouge and New Orleans, with the tradeoff of creating severe flooding in the Atchafalaya Basin, and will also reduce floodwater stress on the Old River Control Structure upstream. By May 15, 2011, a total of nine gates had been opened by the Corps of Engineers. The Corps has estimated that it will take opening one-fourth of the spillway's 125 bays — or 31 bays — to control the flow of the river through Baton Rouge in response to a forecast crest of 45 feet anticipated on Tuesday, May 17, 2011, which must remain below 1,500,000 cu ft/s (42,000 m3/s) of water per second through Baton Rouge to ensure the integrity of the levee system.

Category Morganza Spillway Opens in Louisiana : Image of the Day acquired May 15, 2011 download large image (4 MB, JPEG, 4371x6927) acquired May 15, 2011 download large false color image (1 MB, JPEG, 1407x2511) acquired May 14, 2011 download large image (660 KB, JPEG, 1296x864) On May 14, 2011, the U.S. Army Corps of Engineers opened the Morganza Spillway in an attempt to ease flooding along the Mississippi River in Louisiana. The decision was made to protect the heavily populated areas and infrastructure around the ports of Baton Rouge and New Orleans. The decision is not without cost, however, to the thousands of people who are likely to lose homes and farms within the flood plain downstream. On May 15, the Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite captured this natural-color image (top) of the Morganza Floodway.

The image was acquired at 11:20 a.m. Central Daylight Time, one day after the spillway was partially opened. The lower photo was taken on May 14 by the Army Corps, several hours after water began streaming onto the floodway. The flood control structure, or spillway, includes 125 gates, 11 of which had been opened as of noon on May 16. In the satellite image, the white pixels near the spillway are whitewater churned up by the flow through the gates; the downloadable large image shows this in much finer detail. Square and quadrilateral shapes on the landscape show areas that were cleared for farming or perhaps shaped for flood control earthworks. In the natural color satellite, water ranges in colors of olive, tan, black, and gray, reflecting the different loads of muddy sediment churned up from the bottom; darker areas might also reflect deeper water. Past the spillway, water is more readily apparent along the levee on the south and east side of the floodway, suggesting that there are fewer trees and perhaps lower elevations in those areas.

Potential inundation maps (PDF) from the Army Corps appear to confirm that, as water levels are projected to rise to 10–15 feet (3–4.5 meters) in the southern and eastern areas and 5–10 feet (1.5–3 meters) in the northern and western areas in the image above. Green areas do not necessarily mean a lack of water. As the aerial photo shows, much of the floodway is covered with trees that will shield the water below from the eyes of satellite sensors. Water is somewhat easier to spot in the near-infrared and shortwave infrared image linked below the top photo. Video of the opening of the Morganza Floodway can be viewed online here. The floodway was last opened in 1973, the first and only time it was used before 2011. NASA Earth Observatory image by Jesse Allen and Robert Simmon, using EO-1 ALI data. Photograph courtesy Team New Orleans, US Army Corps of Engineers. Caption by Mike Carlowicz. Instrument(s):

Question: The Morganza Spillway (or Morganza Control Structure) is on the western bank of which US river?
Answer: Mississippi River