Improve soil drainage in future food forest - help a newbie out please!

We recently bought a property in coastal Maine (zone 5) and are planning its conversion to a permaculture homestead. We are super excited but it's also our first time working on such a large-scale food-growing project, so we have lots of questions and doubts!

The property is 36-acres in total, the majority of which is a well-established forest that we plan to keep as such. We have an area of about 1 acre that we want to convert to a food forest. It is west-facing, slope of about 8%. There is a small stream crossing it. The stream flows year-round and is usually only a couple of feet wide. However, we just had some major rainfall and it swelled up pretty significantly - the widest point was almost 20 ft. We have been waiting for the soil to thaw enough to do a soil test, but by the looks of all the standing water, I'm guessing it's pretty heavy in clay and with really bad drainage. Most of the trees growing in this section of the property are (unsurprisingly) apple trees, elders, and a few maples.

I think we need to do give our soil some major love before we can even think of successfully starting a food forest. I'm feeling a little overwhelmed with all the options out there, and I was hoping someone could help me straighten them out in my head! These are some strategies I came up with, and I don't know if 1) they make sense/would work/are the right approach and 2) should I apply them all, or only a few? Are there other options I haven't come across yet?

1) Improve stream channel and banks. Right now, the small channel is full of material (twigs, rocks, leaves, but also trash left behind by the previous owners). There are virtually no grasses/shrubs by the banks. I have been thinking that if I created better conditions for the water to flow (remove some material from channel, stabilize banks), there would be less flooding during medium rain events. Any suggestions for species that would help stabilize the banks, or other interesting methods to do so?
2) Build rain gardens in the areas with the worst standing water conditions around the stream.
3) Support the soil by heavily mulching and building up the topsoil with manure/compost/woodchips, in preparation for food forest planting.
4) Potentially build hugelkultur beds? Is this feasible on a 1-acre scale? Or at least in the areas closest to the stream and most likely to suffer from flooding? Should we combine it with 3), by heavily mulching the area we are dedicating to the food forest and building a couple of hugelkultur beds where needed?

Also, would it be a reasonable timeline to get some of this work done over the spring and summer, and start planting some trees in the fall? We have been clearing some of the elders out, and I'm now realizing it might have been a mistake. We didn't realize the soil situation was so bad until we had this big rainfall and we thought it wouldn't have been a true newbie mistake to cut the elders down. But maybe their root system was actually improving the drainage ?If so, I wouldn't want to leave the soil bare for too long ... and I'm hoping we could get it ready for some planting in the fall.

Any help would be greatly appreciated! Thank you so much!

Giulia

I like your 1st suggestion to clean up debris and your 4th suggestion might work to keep plants from being washed away or drowned during flooding. The 2nd idea for a rain garden might also work.

I feel the 3rd suggestion would add to the problem when flooding occurs.

Looking at soil types for that property (I think) along your creek is revealing. Judging by the USDA Soil Map you have a number of areas with a very shallow water table. I can post a map if you want.

BuB—Lamoine silt loam, 3 to 8 percent slopes - Landform: Marine terraces, river valleys - Depth to water table: About 6 to 17 inches
Typical profile: Ap - 0 to 7 inches: silt loam, Bw - 7 to 13 inches: silt loam, Bg - 13 to 24 inches: silty clay loam, Cg - 24 to 65 inches: silty clay

Sn—Scantic silt loam, 0 to 3 percent slopes - Landform: Marine terraces, river valleys - Depth to water table: About 0 to 12 inches
Typical profile: Ap - 0 to 9 inches: silt loam, Bg1 - 9 to 16 inches: silty clay loam, Bg2 - 16 to 29 inches: silty clay, Cg - 29 to 65 inches: silty clay

SuC2—Suffield silt loam, 8 to 15 percent slopes, eroded, - Landform: Coastal plains - Depth to water table: About 18 to 30 inches
Typical profile: H1 - 0 to 6 inches: silt loam, H2 - 6 to 23 inches: silt loam, H3 - 23 to 33 inches: silty clay, H4 - 33 to 65 inches: silty clay

Ls—Limerick-Saco silt loams - Landform: Flood plains - Depth to water table: About 0 to 12 inches
Typical profile: H1 - 0 to 8 inches: silt loam, H2 - 8 to 16 inches: silt loam, H3 - 16 to 65 inches: silt loam

PfC—Paxton very stony fine sandy loam, 8 to 15 percent slopes - Landform: Drumlinoid ridges - Depth to water table: About 30 to 42 inches
Typical profile: Oa - 0 to 2 inches: highly decomposed plant material, H1 - 2 to 8 inches: fine sandy loam, H2 - 8 to 20 inches: fine sandy loam, H3 - 20 to 65 inches: fine sandy loam

When it's on a large scale, I would think that the best is to pick up your species to be flood tolerant.

An option I would consider is to plant following keylines. This way, water is moved from creeks to hillsides, reducing water stress around the creeks.

Cleaning debris might help, at least aesthetically :)
Well, you can improve the banks, or you can build some detention ponds. A pond will collect excess rainwater and will release it slowly, preventing damage, or even it will infiltrate into the aquifers. Here we use cannes in our ponds, not sure about your climate. In a detention pond, you have to design for normal water flow and for runoff water in case it ends up completely filled. A permeable rock dam will do.

Most any kinds of bushes will help with erosion along the creeks, so you could arguably have blueberry, currant (assuming laws don't apply in Maine), Rock berry, Serviceberry & maybe Chokeberry & Thimbleberry. I don't know if Thimbleberry grows on the coast, or not, let along whether it's a thistle or a vine. But, those are some edible suggestions.

The retention ponds would be best suited for the places where you're having the worst drainage. You could dig spillways between them & your creeks, if they're not already attached. If you give them shallow areas, you could also stock them up with other edibles, like Wapato, whatever your native equivalent of Canadian Lily is or Cattail & get some bergamot, wild rose & other wildflowers on the shores, maybe? Of course, they don't need to be too big. Getting 1 or 2 native water-hungry trees, like willows, on the edges of such places might be helpful.

At the end of the day, I think this stuff is going to be a process for all of us attempting such things, so just trial & error. You don't necessarily need to get everything all at once.

You can tackle the soil any way you want. There are only certain species that absolutely need it & I think only 2 edibles are on the list-- Serviceberry trees (no clue if the bush variants are fine, just make sure you get the local species though.) & Solomon's Seal. Whatever you do, though, just try to keep worms out of it. There's a strong likelihood that you have some anyway, in which case I don't think there's that much more harm you could do, but between that & the current drainage issues, it's going to be a bit of a pain for a while keeping soil where you want it.