Copper Sulfate for Septic Line Roots: Does It Work?

Copper sulfate is a traditional treatment for roots in septic lines, but scientific evidence of effectiveness is lacking. Soil scientist Dr. Larry West notes:

• Modern drainfields use perforated pipe surrounded by gravel; large roots rarely penetrate.
• Copper accumulates as a hazardous metal in soil.
• Most root-control products exploit fear rather than need.

If You Try It

Place copper sulfate in the distribution box (not down drains) to avoid harming tank bacteria.

Better Long-Term Solution

Install an 18-inch-deep root barrier trench lined with aluminum flashing between trees and the drainfield.