Ameren Missouri will consider dredging or excavations only when all other options have been exhausted. The numbers below correspond to Drawing 3-4
The following excavation or filling activities are prohibited
- Dredging - Excavation or filling of wetlands.
- Dredging - Excavation or filling of stream channels, the mouths of streams, or heads of coves.
- Dredging - Excavation from areas above elevation 655.5 feet Union Electric Datum (UED).
- Dredging - Excavation from areas below elevation 652.0 feet UED, except immediately under an existing boat lift. Excavations to elevation 650.0 feet UED will be authorized only to accommodate an existing boat lift.*
Dredging may be necessary to access existing shallow water mooring facilities and private properties. Limited excavations, when allowed, must meet the following standards:
- Dredging must be located a minimum of 25 feet lakeward of the ordinary high water mark (OHWM) elevation 658.5 feet UED.*
- Dredging to accommodate an existing boat dock must have bottom excavation dimensions equal to the outside dimensions of the existing dock.
- Dredging to accommodate a proposed boat dock must not have a bottom excavation dimension greater than 900 square feet, except where community docks are proposed. Excavation under community docks will be permitted only where significant areas of shoreline and/or shoreline habitat can be preserved by installing the community dock.
- Dredging must have a 1 vertical on 3 horizontal slope between the bottom of the excavated area and the natural lake bottom at the boundary of the excavation.*
- Boat lanes must not be wider than 15 feet at the bottom, and side slopes must be no steeper than 1 vertical on 2 horizontal or shallower than 1 vertical on 3 horizontal.*
- Dredging material must be disposed of in a non-wetland site above elevation 665 feet UED, and stabilized so as to not re-enter the lake. Applicants must designate the disposal location and may be required to provide a stabilization plan.
All proposed excavation-dredging shall require review and approval from all appropriate resource agencies and a permit from Ameren Missouri and the Corp of Engineers.
Excavation-dredging of lakebed sediments for non-commercial use by private individuals for landscaping purposes or backfill for seawalls is prohibited.
Excavation-dredging cannot take place between March 15 and June 15 of any year to prevent disruption of fish spawning activity.
Excavation-dredging that involves the removal of more than 500 cubic yards of material also requires approval from the FERC.
Dredging beneath boat docks should be conducted as a last resort. Before resorting to excavation, property owners should attempt to relocate the dock to frontage containing deeper water or extend the dock over deeper water by installing a walkway of sufficient length so as to eliminate the need for excavation, provided the location of the dock meets all other permitting guidelines.
Fill will not be allowed on project property without permission.
Sample drawings are shown in Drawing 3-4
*These limits may be imposed as conditions on issued permits or varied slightly, if appropriate, when the excavation application otherwise satisfies the criteria for minor excavation under normal size docks.