It’s not every day that I need to drain the water from a hole or two, but it definitely happens more times than I am prepared for and lately seems to be a more regular occurrence than usual. In the past, we have used full-blown, heavy-duty electric trash pumps that are hooked up to large-diameter hoses, similar to fire hoses. And for minor water events, a shop vacuum with the air filter removed has generally been fine. Both options worked, but what I really wanted was something small, portable, and—preferably—cordless to add to our core tools.

What I landed on was the Milwaukee M18 (model 2771-20) transfer pump. It isn’t a new tool; in fact, I think it’s one of the first cordless transfer pumps to come to market. It weighs just under 8 pounds without a battery and has a small footprint, measuring about 13 inches long, so it doesn’t take up much space in our job box. Milwaukee states that the nonsubmersible pump’s maximum flow rate is 8 gallons per minute and, with an XC5.0 battery, you can expect to pump as much as 240 gallons of water at a rate of 480 gallons per hour on a single battery charge, which seems to be just about right based on our experience. According to Milwaukee, the pump is not designed to be used with flammable fluids such as fuel oil or gasoline; in fact, using it to pump anything other than clear water—think water tanks and hot water heaters—will void the warranty.

Milwaukee’s cordless M18 transfer pump can move as much as 240 gallons of water on a single charge.

One thing I didn’t know about and wasn’t expecting was a recommendation in the product manual calling for a 6-foot length of heavy-duty, 3/4-inch-diameter hose on the inlet side, while the vast majority of garden-type hoses are considered medium duty and 5/8 inch in diameter. The concern about using a lighter-duty and more-restrictive hose is the possibility that the pump’s suction will cause the hose to collapse. The pump’s outlet is also a 3/4-inch-diameter brass fitting.

To use this pump on our jobsites, we upfit the inlet hose with a filter made from a length of drilled-out PVC pipe with a cap and a PVC hose fitting. We covered the pipe with a laundry lint-trap filter purchased at a big box store and wrapped the assembly in filter fabric to prevent stones and debris from clogging up and possibly damaging the pump’s replaceable impeller.

The pump impeller is replaceable, but the author assembled an in-line filter out of a length of PVC pipe and some fittings so that he could use the pump to drain footing trenches filled with muddy water.
The author drilled holes in the PVC pipe, then covered it with a laundry lint-trap filter to keep out coarser grit.
Filter fabric wrapped around the assembly and held in place with a plastic zip tie helps block out finer sediment.

We paid full price for this tool, and because it has proven to be so useful, we would buy it again if ours somehow disappeared from the jobsite. With 18 feet of lift (the ability to pull up water that is below the pump) and 75 feet of head height (the ability to raise water vertically above the pump), this self-priming unit has plenty of power to pump water up from a basement footing and away from a building to an alley or ditch. And for its size and weight, it does this much more quickly than I would have expected. $230 (tool only).

Photos by Jake Lewandowski