DNR, Corps monitoring high hazard dams
June 13, 2008
The Department of Natural Resources and the U.S. Army Corps of Engineers have paired up this week to check privately owned high hazard dams in 20 flood-affected counties of southern Indiana.
Significant progress has been made in evaluating the dams and determining if any emergency steps need to be taken. A dozen two-person teams have been at work in Bartholomew, Brown, Dearborn, Decatur, Franklin, Greene, Henry, Jackson, Jefferson, Jennings, Johnson, Lawrence, Madison, Monroe, Morgan, Owen, Ripley, Sullivan, Vigo and Wayne counties.
The following general information is designed to answer most questions about dams and the regulation process in Indiana.
Frequently Asked Questions:
Exactly what is a dam?
A dam is a man-made barrier constructed for the purpose of storing or diverting water. It usually is built across a stream or river and usually consists of earthen materials or concrete. Many of the existing dams in Indiana are relatively old (30 years or more), making safety inspections and regular maintenance extremely important practices.
Who is responsible for keeping a dam safe?
The Indiana General Assembly has established dam safety laws to protect the citizens of the state. Generally, the laws are intended to ensure the dam owner maintains his/her dam in a safe manner that minimizes potential safety risks downstream to lives and property. Since dam owners can be held accountable for any damage that results from the failure of their dams, they should do whatever is necessary to avoid injuring persons or property.
Who makes sure dam owners are doing what’s required?
The Department of Natural Resources has the statutory authority to regulate dams in Indiana. The DNR oversees the inspections of about 1,100 dams statewide.
Are all dams the same?
No. The DNR regulates dams that meet one of three criteria - the drainage area above the dam is greater than 1 square mile; the dam embankment is greater than 20 feet high; or the dam impounds more than 100-acre feet of water.
These dams fall into three “hazard” categories - low, significant, and high. “Hazard” refers to the level of damage downstream if a dam fails. There are about 600 low hazard dams in Indiana, about 250 in the significant category, and about 250 in the high category.
What’s the difference between “high” and “low” hazard?
A high hazard structure is one in which its failure may cause the loss of life and serious damage to homes, industrial and commercial buildings, public utilities, major highways, or railroads.
Failure of a significant hazard structure may damage isolated homes and highways, or cause temporary interruption of public utility services.
Failure of a low hazard structure may result in damage to farm buildings, agricultural land, or local roads.
How often are dams inspected?
State law requires a DNR inspection of low hazard dams once every five years, and once every three years for significant hazard dams. When it comes to high hazard dams, state law requires the owner of the dam to have an inspection by a licensed professional once every two years.
What happens in a dam inspection?
Actually, it’s rather complex. A responsible dam safety program should include four types of inspections - formal technical inspections, maintenance inspections, informal inspections, and special inspections. A formal technical inspection is the most comprehensive and usually includes review and analysis of available data and plans, a field examination, and a final report. The field exam is performed by a team of one or more professional engineers, geologists or qualified technicians, accompanied by the dam owner or his/her representative. Depending on the type of dam, a field exam can take 2 to 3 days for a team of experts to complete and may cost the owner $2,500 to $4,000.
Does a dam inspection guarantee the dam is safe?
Absolutely not. An inspection is only a snapshot of the dam’s relative safety status at that time while providing the owner with information on necessary repairs. Year-round vigilance by the owner using informal inspections coupled with special inspections and proper maintenance practices are far better tools for ensuring the long-term integrity of a dam.
What about levees? Are they handled the same as dams?
It depends on the type of levee. Some levees are designed and built for flood control. Others are agricultural structures not meant for the same sort of flood control but instead designed to divert water from crop fields, or to prevent topsoil erosion in the event of high water. Flood control levees are inspected. Agricultural levees are not.
So, with the recent floods, what’s the status of dams in impacted areas?
Personnel from two DNR divisions - Water and Reclamation - have teamed up with U.S. Army Corps of Engineers to form two-person teams that are performing damage assessment of approximately 100 high hazard dams in 21 southern Indiana counties. It is important to note these are not dam inspections in the truest sense, but rather spot checks to evaluate visible damage and determine if there is any immediate danger.
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Free Memorial Day Events at North Bend and Beech Fork State Parks
May 20, 2008
The traditional commemoration of Memorial Day is May 30, but Memorial Day Weekend will be celebrated this weekend, May 23-26, by families, friends and reunions at the picnic tables and swimming pools of West Virginia state parks and across the state.
Two parks scheduling free concerts and performance Memorial Weekend are North Bend and Beech Fork state parks. The events are open to the public to attend and there is no charge.
- North Bend is fast becoming a bluegrass music hot spot according to Jennifer Cogar, program and activity coordinator. “Our amphitheater is open air and family friendly. We have a wealth of bluegrass talent in our region and we’re pleased to offer a nice lineup of events at the amphitheater this summer.” Cogar’s musical guests Memorial Weekend are East Run Band on May 23 and Rocky Mountain Bluegrass on May 24. Shows begin at 7 p.m. each night and are two hours. There is no charge to attend. Bring a lawn chair or a blanket for seating. The events are alcohol free and attendees are asked to not litter the grounds. For more information contact: North Bend State Park (304) 643-2931. North Bend State Park is located in Ritchie County minutes off U.S. Route 50 between Cairo and Harrisville.
- Beech Fork features Mick Souter on May 24. Souter sings and tells stories that celebrate the people, the history and the beauty of the Mountain State. He performs on many different musical instruments, including the banjo, guitar, dulcimer, fiddle, mandolin, and harmonica. His performance, “Celebrate West Virginia,” focuses on the heritage of the state. Souter’s performance is at 7 p.m. and will be located at the park’s activities building. For more information contact Beech Fork State Park, (304) 528-5794. Beech Fork State Park is located in Cabell and Wayne counties and accessible from Interstate 64 near Barboursville. Park locations and directions are online or call the park.
Events and activities are added and posted frequently on the West Virginia State Parks Web page. For monthly information about events, packages or new additions to state parks, subscribe to the e-mail newsletter. For information about West Virginia’s state parks and more events and activities throughout the summer go online, www.wvstateparks.com
and click Calendar of Events.
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Hunters Reminded of Conservation Area Closures
April 26, 2008
Eleven areas in southeastern Missouri have been closed due to flooding.
KENNETT, Mo.-Turkey hunters who normally head for conservation areas in southeastern Missouri should check the list of closed areas before opening day of spring turkey season. They may find their favorite areas closed.
The Missouri Department of Conservation closed 11 of its areas last week due to flooding. Those conservation areas are:
–Wolf Bayou, Girvin, Black Island, DeSoto and Gayoso Bend in Pemiscot County;
–Ten Mile Pond and Seven Island in Mississippi County;
–Donaldson Point in New Madrid County;
–Coon Island in Butler County;
–Ben Cash and Hornersville Swamp in Dunklin County.
–Parts of Duck Creek CA in Bollinger, Stoddard and Wayne counties
Conservation Department officials said the closures serve two purposes. One is to keep visitors out of areas where high water has created unsafe conditions. The other is to protect turkeys and other wildlife that have been forced to take refuge from flooding on a limited amount of high ground.
“Chapter 7 of Missouri’s Wildlife Code says that wildlife may not be pursued or taken while trapped or surround by floodwaters or while fleeing from floodwaters,” said Conservation Department Protection Regional Supervisor Ken West. “We certainly are experiencing that now. We encourage landowners who have property near the closed public areas to restrict hunting activity to help protect wildlife fleeing high waters.”
For more information, contact the Conservation Department Southeast Regional Office, 573/290-5730.
-Jim Low-
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