According to this 2001 ND State report corn (&sugarbeets) is NOT a reason for the ND flooding

[underpants]

In case you were wondering like I was.
.........

Agribusiness & Applied Economics Report No. 432a October 2001
(Updates Report No. 432, December 1999)
The Feasibility of Wetland Restoration to
Reduce Flooding in the Red River Valley:
A Case Study of the Maple River Watershed,
North Dakota
Steven D. Shultz
Jay A. Leitch
Department of Agribusiness and Applied Economics
Agricultural Experiment Station
North Dakota State University
Fargo, North Dakota 58105-5636

The Maple River Watershed, a typical, agricultural-based sub-watershed of the Red River
Valley, covers about 1,600 square miles in eastern North Dakota, and is located in the southern
part of the Red River Valley, west and northeast of the city of Fargo and south of Grand Forks.
Soil productivity and, hence, cropping intensity and land values decrease in a westerly direction
away from the Red River. Principal agricultural crops in the more productive eastern part of the
watershed are wheat, barley, oats, and sugarbeets while in the western reaches wheat is rotated
with potatoes, corn, beans, and forage crops. As much as 55 percent of the original wetlands in
the Red River Valley and the Maple River Watershed may have been drained since colonization
(Dahl, 1990). The National Wetland Inventory (NWI) by the United States Fish and Wildlife
Service includes approximately 45,600 acres of existing wetlands in the watershed, primarily in
its middle and upper reaches, and 2,700 acres of recently drained wetlands.
Wetland Restoration and Flooding

The potential of wetland storage for reducing peak flood flows is recognized as one of the
most poorly understood functions of wetlands (Interagency Floodplain Management Review
Committee, 1994). Nevertheless, several studies and commentary have noted that historical
wetland drainage has magnified the impact of recent large (low-frequency) flood events along
the Mississippi River System (Hey and Philippi, 1995) and in the Red River Valley (Sierra Club,
1998 and 2000). However, these analyses often make the highly unrealistic assumptions that
wetlands are empty at the time of flood events and that all potential wetland storage reduces peak
flood flows during these major floods.

Outside of the Red River Valley, a few studies have used hydrologic modeling to
evaluate the impact of wetland storage on flooding. A frequently cited study of the semi-urban
Charles River Watershed near Boston, Massachusetts, concluded that wetland storage
significantly reduced peak flood levels . In
Illinois, it was estimated that each percentage increase in wetland area reduced downstream peak
flows on medium sized streams and rivers by 3.7 percent and average flood flows by 1.4 percent
(Demissie and Khan, 1993). A study of sub-watersheds of the Mississippi River hypothesized
that restoring upland wetlands would reduce flood peaks by between 1 and 23 percent with deep
wetlands and between 5 and 9 percent with shallow wetlands, and that wetland restoration was
most effective in reducing flood damage during high-frequency storm events of 25 years or
smaller (Interagency Floodplain Management Review Committee, 1994).

Closer to the Red River Valley, it was estimated through the use of a hydrologic
simulation model in the Little Cobb River sub-watershed of the LeSuer River Watershed in
Minnesota, that historical drainage of wetlands increased annual peak flood discharge by up to
57 percent during high-frequency flood events but a negligible effect on reducing the magnitude
of large (low-frequency) flood events (Miller, 1999). Within the Red River Valley itself,
quantitative analyses of historical land use, drainage, and hydrologic relationships and flooding
has been noted to be problematic due to spatial and temporal limitations of available data (Moore
and Larson, 1980). However, a review and assessment of drainage and flooding issues in the
Red River Valley by Miller and Frink (1984) concluded that increased drainage does have an
effect on small (high-frequency) flood events and a diminished or negligible effect on largescale,
low-frequency flood events.

http://ageconsearch.umn.edu/bitstream/23597/1/aer432a.pdf

http://ageconsearch.umn.edu/

[Name removed]

1. Deleted message

Message removed by moderator. Click here to review the message board rules.

[kestrel91316]

2. Loss of prairie potholes in the area around the Red River probably

plays some role. We destroy wetlands at our own risk.