Safety around dams
Published 12:00 am Saturday, March 22, 2003
This is a second in a series of articles about river navigational hazards. Today’s topic: dams. I have to admit I didn’t know much about inland river dams and their potential hazards until I started researching this topic. In addition, the number of detailed laws that are in effect within the state on establishing dams are also worth reviewing.
Dams are a very use way of controlling the flow of water. Unfortunately low head and conventional dams pose dangers both above and below the dams, to recreational boaters who are conducting
river navigation.
According to Virginia’s Department of Game and Inland Fisheries, &uot;Boat Virginia&uot; – &uot;low head dams vary in eight from one to several feet below the water’s surface. Though their drop may be small, you must never assume you can go over without danger.&uot;
In addition &uot;remember that water going over a low head dam creates a strong recirculating current or backroller (sometimes referred to as the &uot;boil&uot;) at the base of the dam. Even on small rivers, the force of the backroller can trap your boat against the face of the dam, and pull you under water – even while wearing your Personal Flotation Devices (PFD). Be aware that on large rivers or at high water the backroller or boil may be located more than 100 feet downstream of the dam. Most importantly – avoid low head dams!
Conventional dams with their powerhouses and spillways are easily recognizable. You should stay clear both above and below the dams. These areas are usually off-limits.
As mentioned in the introduction, besides the safety concerns it is important that we talk about
&uot;Virginia Dam Safety Act&uot; and the Code of Virginia and Dam Safety Regulations. Construction of unauthorized dams can have a terrible effect on boaters.
First, and most importantly, no person or entity shall construct or alter an impounding structure until obtaining a construction permit.
Second, all dams in Virginia are subject to the Dam Safety Act unless specifically excluded. A dam may be excluded if it:
nis less than six feet in height;
nhas a capacity less than 50 acre-feet and is less than 25 feet in height;
nhas a capacity of less than 15 acre-feet and is more than 25 feet in height;
nis used for primarily agricultural purposes and has a capacity less than 100 acre-feet (should use or ownership change, the dam may be subject to regulation);
nis owned or licensed by the Federal Government; or
n is operated for mining purposes under 45.1-222 or 45.1-225.1 of the State Code of Virginia.
The height of a dam is defined as the vertical distance from the streambed at the downstream toe to the top of the dam.
Before deciding to build a damn or seek a permit, talk with state officials.
Until next week…Boat
Safe…Boat Smart!
LCDR Joe DiRenzo III is a resident of Suffolk and a regular News-Herald columnist.
L