You can choose plants that will grow well in wet soil, but plants will not remove the water.

If you want to eliminate the water, call a plumber and ask why the sump is draining to one area and so close to the surface. It should have been installed to drain into the storm sewer system or into a dry well so that the water does not pool on the surface.

Here is a link that might be useful: Sump Pump Info

It migt also be the perfect place to grow plants that prefer it permenetly wet unavailable to most gardeners.

May I vent? Looking for advice whether and with what to fill in my trench.

We have a very efficient sump pump- fortunately, because apparently we have an underground spring (saw it dripping through the wall!) that would otherwise give us a wet basement. (now finished!) We also live in an urban area with NO storm sewer on our block! Whenever triggered to pump, it puts out 3-4 gallons of water. If it's been lightly raining, like now in spring, it runs evey 15 minutes. Weeks after rain stops, it still runs once an hour. Do the math- that's a LOT of water. The outlet pipe is on the side of the house with the driveway, mostly shade, so, we've been sending it down the drive to the st. which is slippery and wasteful.

I finally dug a trench between the house and driveway, 30'x3', 30"deep at the furthest end, and 18" at the shallow end. I was aiming for a hybrid combining a french drain and a bog garden. So, we made a pvc pipe channel to take the water down under a layer of rock, holes along the bottom of pipe. The trench has a rubber liner with many holes punched for seepage. I figured the worst that could happen is water would either overflow to the driveway or back toward the house and cycle through the system again.

Problem: after a week, the water only got a few inches deep, and seemed stagnant. (perhaps too many holes) So I introduced a turtle fountain, connected to the sump pipe. This is as entertaining as Old Faithful, spewing water every 15 minutes, but the condensed size of tube is stressing the sump pipe indoors, causing a leak. I could detach the fountain and build a mtn. of rocks around the pipe opening, creating a small waterfall, which would still give some movement to the still water. But the water level is still too low for water lilies. This looks like a low creek.

Should I fill in with peat and sand, and plant all my grasses and iris in it, adding other water loving plants?
Should I cover the rocks and pipe with landscape fabric before filling with soil, to keep a cleaner drain area under the soil?

Should I leave the water washing onto it all from above with a waterfall at the surface? or feed water from below?

I know I'm breaking a bunch of rules. Just trying to creatively solve a problem.
Thanks for listening.
-bellflower

Do a web search for "rain garden", tons of information out there including plants that like to grow in wet, moist soil?

A few of my favorites are cardinal flower, joepyeweed and queen of the prairie - they like growing in wet places.