Granular Bentonite Pond Seal 1000 Pounds

Product Code: BENTONITE1000G

Availability:In stock

$919.00 919.00


Natural way to seal leaking ponds, dikes, dams, spillways, etc. Sodium bentonite clay will create a waterproof seal. Apply at the rate of 2-5 lbs. per Square foot.

Granular Bentonite Seal is a high swelling, chemically unaltered, uniformly sized (8 mesh) granular sodium bentonite which contains no additives. When Granular Seal comes into contact with water, it forms a semi solid, gel-like mass which fills formation voids and limits water movement . 

Natural way to seal leaking ponds, dikes, dams, spillways, etc. Sodium bentonite.

  • Seals leaks without draining the pond
  • Clay particles swell when wet, creating a solid layer of leak protection
  • Great for sealing around intake pipes, muskrat holes, cuts and tears in liners
  • Eco-friendly - all earthen ingredients, will not alter water chemistry
  • Apply at two to five pounds per square foot for a 3/4" thick coverage or ten pounds per square foot for 1 1/2" thick coverage

Sealing a pond with bentonite clay is the most effective way for making a pond able to retain water. You can fix the leaking pond with bentonite in many ways like the sprinkle method, blanket method and mix blanket method. The simplest of all is the sprinkle method.

You just have to sprinkle this bentonite clay in the leaking area by hand or by using broadcast spreader. For this method you have to use granular bentonite. You have to use 5 pounds of this bentonite clay for each square foot. Don’t forget to wear a face/dust mask while doing this.

Granular Bentonite Seal offers an economical way to accomplish bentonite grouting. It provides a high concentration of solids for hole abandonment and sealing casing. Granular Seal can be poured dry or used as a mixed grout for tremie placement. This semi solid mass also prevents surface water from following the bore hole to subsurface water supplies.


The amount of bentonite clay that is required to seal a pond depends upon the porosity of pond soil. Porosity is more when high seepage of water occurs. 
Bentonite is a natural substance. It is non toxic to fish.
First remove all the debris from the pond while you add the bentonite clay in the pond. Using the blanket method:

  • Do not leave any blank space.
  • If you don’t want to disturb the bentonite layer then add the water carefully.
  • You have to maintain a good depth of soil layer.
  • Don’t perform this method if the weather is too hot.

Bentonite application rates

Soil type

  • Fair clay : 2 lbs of bentonite per square foot
  • Poor clay : 3 lbs of bentonite per square foot
  • Silty Loam : 3-4 lbs of bentonite per square foot
  • Sandy Loam : 4-5 lbs of bentonite per square foot
  • Sand : 6 lbs of bentonite per square foot
  • Sand and gravel : 6-8 lbs of bentonite per square foot
  • Gravel and fractured bedrock 8-10 lbs of bentonite per square foot

Available in 50 lb polyethylene bags and 3,000 lb bulk bags.

(8 mesh) – Granulated bentonite with no additives
• When contacted by water forms a semi-solid, gel-like mass that fills formation voids and prevents surface water from entering subsurface aquifers.
• Used to seal well casings
• Decommission abandoned bore holes
• Stop loss circulation during rotary drilling

pH: 7.5 – 8.6