A liner alone won't help reduce the need for emergency spreading during winter storms, but adding a cover certainly will. Emergency spreading is usually caused by lagoons filling up faster than expected due to heavy rain and snowmelt.
While a liner's job is to protect the soil below, a cover protects your storage capacity by keeping precipitation out so you have enough room to hold waste until the ground thaws. Without a cover, you're essentially using valuable permit capacity just to store clean rainwater. By keeping the elements out, you maintain control over your schedule rather than being forced to pump during adverse conditions.
