Plumbing – Washer water out from basement

What is probably going on is that your neighbors' weeping tile systems are draining into their sumps, which are then pumped out because they're below grade and there isn't a storm sewer at a lower grade that can be drained into. The weeping tile exists to direct water that soaks into the ground away from your house, instead of letting it collect against your foundation walls and leach through, or worse, freeze and heave against your house in the winter. Depending on your soil type, rainwater can stick around for months in the soil, and you may also have an aquifer or water table nearby that provides a relatively steady source of groundwater into the soil.

So, what I'm saying is that depending on how much rain you've had recently (as in the past few months) it's perfectly normal for your neighbors' sumps to still be filling. Depending on the land grade, it may also be normal that your sump isn't yet filling while your neighbors' are (water will soak more into land that is downhill). Just make sure your sump pump is in good working order and don't worry about it any more, unless you start to see damp areas along the walls or floor of your basement; these would generally indicate blocked, crushed or missing weeping tile.

You should not add an upward bend to the pipe, as that will more likely lead to water always sitting in the pipe.

Instead you should add a check valve (one way valve) to the line. This will allow the pump to push water out, while preventing ditch water from flowing back in.

If the pump is strong enough, it should be able to push water into the ditch even when it's full. Unless the outlet is pointed upstream, in which case you should redirect the pipe downstream.