Lagoon size requirements

• Lagoon size is determined by the number of bedrooms, as well as the annual evaporation and precipitation rates for the geographic region.

• The lagoon size is NOT based on the square footage of the house, or the number of people living in the house because occupancy can change.

• The following formula is used:

Nebraska evaporation and precipitation numbers used in the lagoon size formula:

Nebraska Total Annual Lake Evaporation

(fig18.3 NDEQ Title 124 1999)

Nebraska Total Annual Precipitation

(fig18.4 NDEQ Title 124 1999)

• The top of the dike must be 4 feet wide at the top.

• The lagoon must have a 4 -foot high fence with locking gate. The fence must be on the outside edge of the top of the dike, or 4 feet outside the toe of the dike. A  fence outside the dike is less noticeable, and the 4 -foot distance allows for easier mowing.
• A sign must be prominently placed on the fence warning that the lagoon holds sewage.
• The wastewater line from the house to the lagoon should have a clean-out with a tight-fitting cap every 75 feet or less, or anywhere there is an angle greater than 45 degrees. One clean-out must be located at least one foot above the highest water level and near the outside of the dike embankment.
• The wastewater line must discharge to the center of the lagoon, to a concrete pad.

• Counties may have more stringent regulations than the state, but never more lax.
• Some counties do not allow lagoons - check local zoning restrictions.
• To construct and use a domestic wastewater treatment lagoon, NDEQ state regulations require a 3-acre minimum lot size.
• NDEQ regulations state that lagoons must be at least 50 feet from property lines and 100 feet from drinking water wells.

State regulations give the minimum requirements that must be met. Check local codes.