§ 15-2107. General duties.

1. Upon its organization the board may prepare a plan for the
regulation of the flow of the river or rivers in its district. Such plan
shall show the available and feasibile reservoir sites on such river or
rivers, whether any reservoir now existing can be and should be enlarged
and to what extent, the approximate number of acres of land flowed or to
be flowed by each reservoir, whether any of such land is owned by the
state and if any, how many acres, the number of acres of private land
required, together with the estimated value of the land, and how many
acres, if any, of such land are lands of the state within the forest
preserve. Such acreage shall include such quantity of land surrounding
the reservoir to be created or enlarged as would in the judgment of the
board be required for the protection, maintenance and operation of such
reservoir. The plan shall be accompanied by such maps, profiles and
other data and descriptions as may be necessary to set forth properly
the location and character of the work and of the property to be taken
or damaged, and by estimates of cost of each such reservoir. In case
maps, plans and specifications for any such reservoir at or near the
site thereof, are on file in the office of the department, and in case
any records in any other department of the state government would be an
aid in the preparation of such plans, these shall be available to the
board for such purpose.

2. Upon the completion of such plan if the board approves of such plan
it shall certify it to the department for its approval, and the
department within forty days thereafter may approve the same, or modify
it and approve it as so modified. As so approved by the department it
shall be known as the "official plan" for the regulation of the flow of
the river or rivers of the district. Copies thereof shall be filed in
the offices of the board, the department, and of the county clerk of
each county wholly or partly within the district. Such plan in like
manner may be altered from time to time provided such alteration shall
not affect any assessment already made.