I plan to hook-up a Drummond pump for my fur-shed, I plan to pull the pump for winter but concerned with the feed line freezing where it enters the shed above ground. I have 1-1/2 “poly pipe connected to a foot valve 25’ feet deep and the supply line is buried 8’ deep. The foot valve should prevent water from draining back into the well (my intent was to keep prime) so the pipe should retain water, will this be ok if the poly is open ended. I’m now thinking I maybe should’ve added a check valve to the pump and eliminated the foot valve?

We use that same pump with a check valve on a point at our campsite. Great little pumps. We remove the pump and check valve over the winter. If you could get some of the water out of the pipe adding rv antifreeze might work.

with a foot valve you would want to get the water out of the pipe down 4-5 feet

if you have a T at the top a section of clear tubing and you can probably suck enough out that you will get below frost

do you have pipe up from point , T off the side of the T a union and the pump , off the top of the T a plug you can pull. suck out a bunch of water

this or something like it to suck it out
https://www.amazon.com/Gasoline-Sip...hy=9018907&hvtargid=pla-875220550252


then when your putting your tape measure down the pipe you can feel as you bring it back up from the bottom how deep you are and how many feet of water remain

come spring hook up the pump bring a gallon or two of clean water from the house pour it down the pipe to prime it put the plug back in and turn on the pump you will get a little air and it will work it's way out but should grab prime right away

Just pull the pipe and drain it then put it back down into the well it will be fine . Or if you just have to keep it filled with water get a milk house electric heater near it or wrap it with heat tape and insulation a heat lamp can also help if it's just a small area where your pump is located .
It's not that tough to reprime the pipe that goes to the pump , I wouldn't recommend pouring anything down into the pipe that you don't want to drink just my .02¢ worth .

Good Feedback-
I haven't hooked up the pump yet- I have the 1-1/2" poly run into the shed. I was so focused on keeping the prime that I may have lost sight of a better way of doing it. I can probably siphon water below the frost line with a small enough pump to pull water but not strong enough to open the check valve in the foot pump. I know poly is somewhat forgiving but there will be standing water in the pink area above the freeze zone. Here's my artist rendition of what I have:

if your poly is 8 feet down you just need to get the water out of the vertical run before the pump

a suction hose to get it down below frost line should do fine , being inch and a half you can even probably turn the corner and get down below frost line with a tubing and suction

a T just outside the buidling would be ideal

just getting most of the water out of your Red zone in your drawing should be fine then re-prime with a few gallons of water from the house in the spring

I can only tell you how mine is set up, and it has never frozen on me. Dig down about a foot around your standing pipe, drill a hole and put in a stop (This word is unacceptable on Trapperman). One of those things that they put on a car radiator. (1) It lets the water drain out of the line from the cabin and a foot below ground level. (2) If there is any freezing going on, as the path of least resistance the water will go up the pipe, and drain out. Just remember to close the stop (This word is unacceptable on Trapperman) in the spring.

Pull the pump and bring it in for winter.Siphon out as much water as you can out of the pipe and fill with RV antifreeze.