Benthic barrier, Lake Bottom Blanket

After one month, the lake bottom cover can be removed or moved to a new area where plants are a problem. For example, you can install the Lake Bottom Blanket around May and remove it at the end of June, and have little or no weeds in that area for the rest of the summer!

The Lake Bottom Blanket is shipped in a box without the necessary ballast frames. Ideally, 3/8" (10 mm) rebar should be used as the weight for the lake bottom blanket. 3/8" rebar is available at your local building supply store and most suppliers will cut it to your length. 3/8" rubber end caps are provided to cover the ends of the rebar to prevent damage or injury caused by possible sharp edges of the rebar.

Please note: Hardware stores or renovation centers typically carry ½" (13 mm) rebar; buying this is not recommended for normal use of the blanket. Only 4 caps are included in the package for this size of rebar.

This benthic barrier that acts like an aqua screen or burlap and can be removed annually as needed with minimal effort.  It is reusable for many years.

Weights and recommendations for reinforcing bars (REBAR)

Local purchase - 3/8'' (10 mm) rebars cut into 10-foot lengths

LBB20 (10′ x 20′) - Requires 5 bars

LBB30 (10′ x 30′) - Requires 7 bars

LBB40 (10′ x 40′) - Requires 9 bars

LBB50 (10′ x 50′) - Requires 11 bars

LBB80 (10′ x 80′) - Requires 17 bars

If your installation requires more weight, only the first and last tubes will accommodate ½ inch rebar and for this purpose 4 x ½ inch caps are included. All the other caps included in the box are the standard 3/8 inch for the 3/8 in rebar rods.

Warranty : 1 year coverage on manufacturing defects

Tech Sheet (PDF)

The Lake Bottom Blanket is easily installed in the water if the water weed beds are either in the dormant stage or at any time during the growing season, but it is easier to set up when it is installed before weeds emerge from the water surface. Blankets are 10 feet 9 inches (326 cm) wide regardless of the length required by the customer. Blankets are shipped folded without ballast. The float provided is designed to (A) keep boats that may disturb the blanket away and (B) locate the Lake Bottom Blanket's grab or travel handle.

1-  The first step is to purchase the 10-foot lengths of 3/8 in (10 mm) rebar.

2-  Place the caps included in the box on 1 end of each rebars to protect the blankets from the sharp edges of the rebars (see picture below).

3-  Unfold the blanket to its full width. One end of the tubes is sewn closed; find the open ends of the tubes; insert the rebar into the tubes making sure the side with the cap head first. You will find a zipper on the open ends of each tube. Once the bar is fully inserted, lock it by tightening the tie onto the material; then cut off the free end of the tie.

4-  Place the assembled pleated ribs on the stern of a boat with the plastic over the edge. Attach the two handling lines to the handles of the cover. The line for the end of the shoreline (indicated by the red tape) can be attached with a loop so that it can be easily detached after the blanket is deployed.

The shoreline end must be attached to the outer rib, attached to the shoreline or held by a person on shore.

The offshore line can be attached to the boat or held by a person. 

5-  Release the outermost rib into the water at the shore end of the intended installation. (The ideal water depth is at least 3 feet - the depth may be less if there is assurance that there is no activity in the coverage area). Move the boat away from the shoreline. It will probably take a few minutes for the entire blanket to settle below the surface of the water.

6-  When the last section of the blanket is overboard in the water, using the line attached to the rope handle, pull the blanket reasonably tight before releasing the last section at the bottom of the lake.

7-  Attach the warning float to the line, positioning it so that it remains close to the edge of the blanket. 
Once the blanket is installed, gently pull the blanket toward the shoreline, stretching the blanket reasonably tight again.
The shore side can be disconnected or attached to a shore support. Tying the rope to the shoreline is especially important when aggressive wave action is possible.

 
Note 1: In a deep water installation, it is preferable to use two boats with two people on at least one of the boats. 

Note 2: The blanket should be deployed perpendicular to the shoreline - not parallel, as wave action can move or dislodge it and anyone walking in the water can trip over it.

Note 3: This product has been installed on the windiest of lakes. On those occasions, it might be necessary to anchor the Lake Bottom Blanket with sand bags on the ends or even on top of the rebars depending on situation. 

Video available from the manufacturer.

Assembly : Video
Installation : Video
Removing the barrier: Video
Cleaning : Video

Installation and use (PDF)