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Posts tagged Red River

Ouachita Mountains, Oklahoma, USA

April 7th, 2009 Category: Rivers

Oklahoma, USA - April 4th, 2009

Oklahoma, USA - April 4th, 2009

The Ouachita Mountains are a mountain range located in southeastern Oklahoma (visible here) and west central Arkansas.

Above the mountain range, just left of center, are two large lakes: Eufaula Lake and the Robert S. Kerr Reservoir. The Red River runs just south of the range, providing the border line between Oklahoma and Texas.

Eufaula Lake (left) is a reservoir in Oklahoma, and the largest lake in the state. It is located on the Canadian River, 27 mi (43 km) upstream from its confluence with the Arkansas River and near the town of Eufaula.

Construction of the 975 metres long dam wall began in 1956 and was completed in 1964. The dam holds back a lake area of over 412 square kilometres. A hydroelectric powerstation provides power from the lake waters.

Robert S. Kerr Reservoir (right) is also located in Oklahoma, but is on the Arkansas River. The reservoir is impounded by Robert S. Kerr Lock and Dam at river mile 336.2 (km 541.1) on the Arkansas River, just a few miles below its confluence with the Canadian River.

Red River: North Dakota Sees Record Flood Levels

April 1st, 2009 Category: Floods

North Dakota and Minnesota, USA - March 29th, 2009

North Dakota and Minnesota, USA - March 29th, 2009

The states of North Dakota (center left), South Dakota (bottom left) and Minnesota (right) in the USA as well as the southern part of Canada’s Manitoba (top left) and Ontario (top right) provinces are all visible here. Lake Superior shows its southwestern tip in the upper right corner.

Recently, North Dakota, Minnesota and Manitoba have all been affected by high water levels in the Red River. The Fargo-Moorhead area in North Dakota saw record flood levels.

The flood is a result of saturated and frozen ground, Spring snowmelt exacerbated by additional rain and snow storms, and virtually flat terrain.

Unlike the vast majority of rivers in the United States, the Red River flows northward, which means melting snow and river ice, as well as runoff from its tributaries, often create ice dams, which cause the river to overflow. The valley is essentially flat, leading to overland flooding, with no high ground on which to take refuge.

The river crest was originally predicted to reach a level of near 43 feet (13 m) at Fargo by March 29, although the river in fact crested at 40.82 feet (12.44 m) at 12:15 a.m. March 28, and started a slow decline. The river continued to rise to the north as the crest moved downstream.

Other climate-related factors also influenced the flooding: ground which was already saturated when it froze at the onset of winter, melting snow which could not be absorbed by the frozen ground, and additional precipitation from a rain storm on March 22 and a later snowstorm.

A low-pressure area caused the rain storm on March 22 and by March 25 a total of 15 to 25 cm (6 to 10 inches) fell in the Winnipeg area, and 20 to 30 cm (8 to 12 inches) in southern Manitoba. In northeastern North Dakota and northwestern Minnesota, around 8 inches of snow accumulated from the same storm.

Lakes around Dallas, Texas, USA

March 6th, 2009 Category: Lakes

Lakes in midwestern USA - March 1st, 2009

Lakes in midwestern USA - March 1st, 2009

The city of Dallas and its suburbs, in the state of Texas, USA, is visible as a grey and tan area towards the center left. It is surrounded by many lakes and reservoirs.

The most evident include Lewisville Lake, just northwest of Dallas. It is a man-made freshwater lake located on the Elm Fork of the Trinity River near Lewisville.

The lake is primarily used recreationally for boating and watercraft, however, it was built for flood control purposes and to serve as a water source for Dallas and its suburbs.

Just north of Lewisville Lake is Lake Ray Roberts, a 29,350-acre (119 km2) lake located 10 miles (20 km) north of Denton, Texas. It supplies water to Cooke, Grayson and Denton counties.

Even further north, above Lake Ray Roberts, is the sizeable Lake Texoma, one of the largest reservoirs in the United States. Its surface spreads over 89,000 acres (360 km²) at the confluence of the Red River and Washita Rivers.

It is formed by Denison Dam on the Red River in Bryan County, Oklahoma, and Grayson County, Texas, about 726 miles (1,168 km) upstream from the mouth of the river. The dam and reservoir were created for flood control and generation of hydroelectric power.

Northeast of Dallas are Lake Lavon (above) and Lake Ray Hubbard (below). Both are artificial freshwater lakes located on the East Fork of the Trinity River. Like many of the others in the region, Lake Lavon was designed for flood control, conservation storage, and recreational use.

Lake Ray Hubbard, formerly Forney Lake, on the other hand, was designed to provide water to the North Texas region. It is  impounded by the Rockwall-Forney Dam and measures 22,745 acres (92 km²) in size, with a storage capacity of 490,000 acre-feet (604,000,000 m³) and a maximum depth of 40 feet (12 m). Several areas of the lake have been infested with hydrilla, which contributes to its green color.

East of Lakes Lavon and Ray Hubbard, approximately 53 miles (85 km) east of Dallas, lies Lake Tawakoni. It is an artificial reservoir used for water supply and recreation. It covers 36,700 acres (149 km²) and has a mean storage capacity of 926,000 acre feet (1.14 km³).

The Advancing Red River Delta, Vietnam

February 23rd, 2009 Category: Rivers

Red River Delta, Vietnam - February 23rd, 2009

Red River Delta, Vietnam - February 23rd, 2009

The delta of the Red River (along the coast to the center-left), is a flat, triangular region of 15,000 km². It is  smaller but more intensely developed and more densely populated than the Mekong River Delta.

Once an inlet of the Gulf of Tonkin, the Red River Delta has been filled in by the enormous alluvial deposits of the rivers over a period of millennia, and it advances one hundred meters into the Gulf annually.

The Mekong delta, on the other hand, covering about 40,000 km², is a low-level plain no more than three meters above sea level at any point and criss-crossed by a maze of canals and rivers.

So much sediment is carried by the Mekong’s various branches and tributaries that the delta advances sixty to eighty meters into the sea every year.

Atchafalaya River and Bays along the Louisiana Coast

December 20th, 2008 Category: Rivers

Atchafalaya River and bays, Louisiana - December 12th, 2008

Atchafalaya River and bays, Louisiana - December 12th, 2008

This ASAR (radar) image allows viewers to see currents in several bays off the coast of Louisiana, USA, west of New Orleans. The flow of water moves southward, pouring out of various streams and rivers, towards the Gulf of Mexico.

The bays visible are, from left to right, Vermilion Bay, West Cote Blanche Bay, East Cote Blanche Bay and Atchafalaya Bay.

The main river visible (top right) is the Atchafalaya River, a distributary of the Mississippi and Red rivers. It is approximately 170 miles (270 km) long.

Formed near Simmesport at the confluence of the Red River with the Mississippi, it meanders south as a channel of the Mississippi, through extensive levees and floodways, past Morgan City, and empties into the Gulf of Mexico in Atchafalaya Bay approximately 15 miles (25 km) south of Morgan City.

The river is now forming a new delta in the bay – the only place on the Louisiana coastline that is gaining ground.