Major flooding of the Big Sioux River, other streams, lakes, and general flooding, which began with a rapid March snowmelt, continued through April. Water levels, having fallen from March peaks, rose again at various times during the month, and were generally falling again by the end of the month. However, any fall of water levels was very slow. Widespread flooding of farmland continued. Many roads remained flooded with heavy road damage being reported in some areas. High water and groundwater levels resulting from record precipitation in the previous year was the main reason that improvement was so slow.

Flood in MINNEHAHA, SOUTH DAKOTA
From 01-APR-11 00:00:00 to 30-APR-11 23:59:00 (CST-6)
Location: BUFFALO TRADING POST
Flood cause: Heavy Rain / Snow Melt
Property damage: 100.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

Minor to moderate flooding of the Big Sioux River, as well as flooding of lakes and lowlands in the county, continued through April, though flooding generally abated. Some farmland remained flooded, both near to and away from the Big Sioux River. The Big Sioux River crested at 2.2 feet above flood stage at the North Cliff Avenue station in Sioux Falls on April 16th, a crest lower than the major flooding of March. A few roads remained covered by water, and there was some road damage. High water and groundwater levels from record precipitation in the year 2010, a main reason the flooding onset was so fast in March, was also a main reason that the flooding subsided so slowly during April.

Flood in LINCOLN, SOUTH DAKOTA
From 01-APR-11 00:00:00 to 30-APR-11 23:59:00 (CST-6)
Location: TEA
Flood cause: Heavy Rain / Snow Melt
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Minor to moderate flooding of the Big Sioux River, as well as flooding of some lakes and lowlands in the county, continued through April, though flooding generally abated. Some farmland remained flooded, both near to and away from the Big Sioux River. A few roads remained covered by water, and there was some road damage. High water and groundwater levels from record precipitation in the year 2010, a main reason the flooding onset was so fast in March, was also a main reason that the flooding subsided so slowly during April.

Flood in UNION, SOUTH DAKOTA
From 01-APR-11 00:00:00 to 30-APR-11 23:59:00 (CST-6)
Location: ALSEN
Flood cause: Heavy Rain / Snow Melt
Property damage: 100.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

Minor to moderate flooding of the Big Sioux River, as well as flooding of some lowlands in the county, continued through April, though flooding generally abated. Some farmland remained flooded, both near to and away from the Big Sioux River. The big Sioux River crested at about 3 feet above flood stage near Hawarden and Akron, iowa, on April 22nd. A few roads remained covered by water, and there was some road damage. High water and groundwater levels from record precipitation in the year 2010, a main reason the flooding onset was so fast in March, was also a main reason that the flooding subsided so slowly during April.

Flood in MOODY, SOUTH DAKOTA
From 01-APR-11 00:00:00 to 30-APR-11 23:59:00 (CST-6)
Location: COLMAN
Flood cause: Heavy Rain / Snow Melt
Property damage: 200.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

Major flooding of the Big Sioux River, as well as flooding of lakes and lowlands in the county, continued through April, though small stream flooding abated and flooding in other areas such as the city of Flandreau abated some. Some farmland remained flooded, both near to and away from the Big Sioux River. A few roads remained closed by the flooding for part of the month. Water was covering some other roads, mainly from flooded lowlands. Some roads were damaged. High water and groundwater levels from record precipitation in the year 2010, a main reason the flooding onset was so fast in March, was also a main reason that the flooding subsided so slowly during April.

Flood in BROOKINGS, SOUTH DAKOTA
From 01-APR-11 00:00:00 to 30-APR-11 23:59:00 (CST-6)
Location: BRUCE
Flood cause: Heavy Rain / Snow Melt
Property damage: 500.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

Major flooding of the Big Sioux River, as well as flooding of lakes and lowlands in the county, continued through April, though small stream flooding abated. Much farmland remained flooded, both near to and away from the Big Sioux River. Flooding around the south end of Lake Pointsett in the northwest part of the county continued in particular to be damaging. The Big Sioux River crested at 3 feet above flood stage near Brookings on April 6th. Some roads remained closed by the flooding for part of the month. Water was running over other roads, from flooded lowlands, lakes, and the Big Sioux River. Some roads were heavily damaged. Some homes and businesses were still flooded. High water and groundwater levels from record precipitation in the year 2010, a main reason the flooding onset was so fast in March, was also a main reason that the flooding subsided so slowly during April.