Swine manure storage pits may start to fill up faster. In general, a 1,000-head barn manure storage pit holds approximately 420,000 gallons. A common practice is to empty the pit completely in the fall, and half in the spring. This would add approximately 630,000 gallons of manure per 1,000-head finishing barn. An increase of 20 percent in manure volume could imply an extra 126,000 gallons of manure to pump out per year and the added cost of removing that manure from the pit (McManus, 2011). 2 2McManus, Daniel. 2011. Personal communication. D.V.M. Young Animal Specialist - Swine. Purina Animal Nutrition LLC.