t of the same where there shall happen to be the deepest water,
which shall be in width at least ten feet in the clear, in length
at least three times the height of the dam, and that the bottoms
and sides thereof shall be planked, and that the sides shall be at
least fourteen inches deep, so as to admit a current of water
through the same twelve inches deep, which shall be kept open from
the tenth day of February to the last day of May in every year....
And be it further enacted by the authority aforesaid, That if any
such owner or proprietor shall neglect or refuse so to do, within
the time aforesaid, the person so offending shall forfeit and pay
the sum of five pounds of tobacco for every day he or they shall so
neglect or refuse....

Still the fundamental problem was not solved; fish were not by-passing
the remaining obstructions in sufficient quantity to maintain the
expected harvest. After various amendments and additions this explicit
definition of a fishway or slope was enacted into law in 1771:

That a gap be cut in the top of the dam contiguous to the deepest
part of the water below the dam, in which shall be set a slope ten
feet wide, and so deep that the water may run through it 18 inches
before it will through the waste, or over the dam, that the
direction of the said slope be so, as with a perpendicular to be
dropped from the top of the dam, will form an angle of at least 75
degrees, and to continue in that direction to the bottom of the
river, below the dam, to be planked up the sides 2 feet high; that
there be pits or basins built in the bottom, at 8 feet distance,
the width of the said slope, and to be 12 inches deep, and that the
whole be tight and strong; which said slope shall be kept open from
the 10th day of February to the last day of May, annually, and any
owner not complying to forfeit 5 pounds of tobacco a day.

The effort was of little avail. Before many dams could be so
laboriously modified the Revolutionary War arrived to obscure placid
matters like fish conservation.

The diaries of the 18th Century Virginia planters abound with
references to seafoods. Most of them lived either on or within easy
distance of Tidewater. Most of them had nets and other fishing
implements of their own and crews among the slaves to work them.
Whenever their needs required, an expedition was made. Perhaps there
was