Sodium Bentonite

The most effective organic waterproof and chemical-proof sealant on the market

Benseal, a sodium bentonite product, is a natural sealant used for stock and recreational ponds, dairy or sewage lagoons, and even city landfills. 

It’s effective as a hole plug, for controlling dust on highways and roadways, and treating porous soils. In fact, the federal government and most states require a liner of sodium bentonite or similar material to seal toxic waste lagoons and abandoned water and oil wells.

At Sturgis Materials, a sodium bentonite supplier near you, we recommend its use as a pond sealant for your outdoor landscapes and for basement waterproofing and leakage prevention.

Types of Bentonite Clay

Sodium bentonite is one of a family of bentonite clays. It is a chemically inert, organic material from the earth and comes in powder form. Many companies sell bentonite clay for a variety of purposes.

Although all bentonites contain a percentage of other natural minerals, like aluminum oxide, magnesium oxide, and potassium oxide, there are only two types of bentonite clay:

  1. Sodium bentonite clay, which has a natural swelling ability that’s maintained throughout its use. It can swell 15 to 18 times its dry size.
  2. Calcium bentonite clay, which is non-swelling and short-lived.


That is why you want the highest quality sodium bentonite, also known as Benseal, which will bond with the soil to create an impenetrable liner. During production, Benseal manufacturers filter out sand and silt, leaving nearly pure sodium bentonite clay as a result.

Frequently Asked Questions about Sodium Bentonite

Follow our application instructions in these quick and easy guides:


If you’re unsure of your ability to do it yourself, Sturgis Materials recommends hiring a professional.

Benseal forms an impermeable dam on the exterior wall of your basement or foundation. To repair a foundation crack or leak using sodium bentonite, the waterproofing or foundation contractor first locates the site of the crack from the exterior of the home.

After digging a small hole against the foundation to the bottom of the footing, the contractor fills it nearly to the top with the clay powder and covers it with soil, leaving no outward sign of the repair.

In average soil conditions, Benseal absorbs water from the surrounding earth, which causes it to expand and harden to seal the crack. Dry conditions may require additional water to begin the sealing process.

Purchase Sodium Bentonite Near You

Sturgis Materials carries Benseal in 50-pound bags, which can be purchased in small quantities or by the pallet, with available shipping to your home or job site. We regret that we are unable to ship to Alaska or Hawaii.