WASTE MANAGEMENT
PIH-21
pork industry handbook
COOPERATIVE EXTENSION SERVICE • PURDUE UNIVERSITY • WEST LAFAYETTE, INDIANA
Systems of Runoff Control
Authors
Dale H. Vanderholm, University of Illinois
John C. Nve, Purdue University
Reviewer
James F. Frank, Springfield, Illinois
Runoff from open feedlots contains animal manure, spilled feed, and other materials which should not be allowed to enter streams. Runoff control is or soon will be mandatory in most states, and satisfactory methods of runoff control are available for almost every situation. These may be simple or elaborate and can range from relatively low cost to expensive. Almost every system requires individual planning owing to variations in lot size, configuration, topography, soil types, rainfall, and other factors such as lot management and local regulations. However, the basic principles of controlling runoff are very similar throughout the country, and these will be used in this publication to provide guidelines for planning runoff control systems. As nomenclature of system components tends to vary from state to state, more than one name for the same component may be used. A common configuration for runoff control systems is illustrated in Figure 1.

Rainfall and snowmelt are the major causes of runoff; urine and leakage from waterers also causes runoff in some situations. Design flow and storage capacities are
usually based on rainfall intensities and amounts (to be discussed in more detail later). Research has shown that it is seldom practical to treat runoff so that it can be discharged to surface waters, so in the systems to be discussed, land application is the only disposal method considered.

Runoff Control System Components
Clean Water Diversion
To minimize the amount of water which must be handled through a runoff control system, unpolluted outside surface water should be prevented from entering the lot. This includes building roof water. This can be done by the use of diversion terraces, channels and roof gutters. Diversion channels and terraces may be either earthen or paved, with earth used most commonly because of its low cost.

Runoff Collection
Lot runoff must be collected and directed to the settling and storage components of the runoff control system. Some lots may have a single outlet point, making collection very simple, while others with slopes in more than one direction and multiple outlet points may require complex collection systems or even more than one complete runoff control system. Curbs, terraces, channels, dikes and pipes are examples of components used to collect lot runoff and direct it to settling facilities and/or storage or disposal.

Settling Basins (Debris Basins)
Settling basins are commonly used to partially treat lot runoff before it enters holding ponds or infiltration areas (vegetative filters). These basins receive runoff from the collection system, allow a portion of the solids to settle and allow the liquid to dram to storage or disposal. Settling basins will remove 50-85% of the manure solids from the lot runoff. This is an important step as the basin prevents solids from reducing storage capacity in the holding ponds or from being deposited in infiltration areas. The solids