Recreation
Ballast Pump
The electric pump that moves water into and out of a boat's ballast tanks or sacs, available as reversible flexible-impeller pumps or one-directional aerator pumps.
Ballast Pump is a term from limnology — the scientific study of inland waters. The detailed explanation below covers the definition, why the concept matters to lake water-quality interpretation, and how it intersects with the LakeGrade rubric. Reading Ballast Pump alongside the LakeGrade rubric helps make the rubric's structure intuitive — each grading parameter maps directly onto an established limnological concept.
The per-lake pages on LakeQuality always show the specific Ballast Pump value for that lake, so you can move from the general concept to the specific lake without leaving the site.
What It Means for Your Lake
A ballast pump fills and drains the water that weights a wakesurf boat. Two main designs exist. Reversible (flexible-impeller) pumps use a water-lubricated flexible impeller to both fill and drain through a single bottom port; they are self-priming, act as a built-in check valve, and need a pump timer to avoid running dry. Jabsco first developed reversible ballast pumps in partnership with MasterCraft. Aerator pumps are one-directional units originally designed for fishing-boat livewells; they accelerate water at higher velocity for the fastest fill and drain times but require separate fill and drain pumps, must be mounted below the waterline, and are not self-priming. Aerator systems run quieter, last longer, and use less energy.
Frequently Asked Questions
What is ballast pump?
The electric pump that moves water into and out of a boat's ballast tanks or sacs, available as reversible flexible-impeller pumps or one-directional aerator pumps.
Why does ballast pump matter for lake health?
A ballast pump fills and drains the water that weights a wakesurf boat. Two main designs exist. Reversible (flexible-impeller) pumps use a water-lubricated flexible impeller to both fill and drain through a single bottom port; they are self-priming, act as a built-in check valve, and need a pump tim...
Related Terms
Added weight (water-filled bags or hard weights) placed in the boat to sink the hull deeper and build a bigger, more defined wake.
A permanently installed ballast system with fixed plumbing—pumps, hoses, intakes, vents, and drains—that fills and empties hard tanks or sacs automatically without manual hoses.
The overflow tube on a ballast bag that lets trapped air escape so the bag fills fully and prevents it from overfilling beyond its compartment.
A soft, fillable PVC ballast bag placed in a boat's lockers or floor to add water weight for wakesurfing, named after FatSac, the original and best-known ballast-bag manufacturer.
A rigid, molded ballast tank built below the floor of a wake boat that holds water weight without occupying storage or seating space and avoids the mildew issues of soft bags.
Source: EPA National Aquatic Resource Surveys, 2026.