Is the swamp impacting your usage of the yard? Spongy ground muddying up and looking bad? How is the rock garden supposed to help? And unless the water is conveyed off site I think your swamp is here to stay.
Personally I’d plant a native rain garden, Joe pye, iron weed, button bush, sedges, bulrushes
Thx. I guess I pretty much understood it - I just had never heard of the gravel filled barrel at the collection point. As you observed, the silting does seem a potential issue. As I understand it, you have to be somewhat careful as to the types of stone you use in such applications.
In our current house and our last one, we’ve had portions in the back of our yards which had standing water following heavy rains. We just were happy that the water gathered there instead of in our basement, and planted plants that could stand periodic inundation.
One other wrinkle is to check and make sure your neighbors haven’t built their property up or installed swales/drains which direct their water towards YOUR yard. We had one such incident in the past, where a neighbor directed his downspout extension so it dumped in our back yard. And our current back neighbor built a shed where it seems to impede the flow/dissipation of surface water. But not a big deal (and no the biggest way he is a jerk!). 
Plant a willow. Will soak up tons of water and provide years of drama! 
Thing is the set up in the picture us usually for that tube to deliver water TO the dry well FROM where is is pooling.
If French drains are used to disperse then then need to drain into an area outside of the area that is swamped.
You had already explained the set up just fine.
Part of the drama being their roots creeping into your pipes and when they fall over!
I love rain gardens though!!!
Now that you say that, I see what you mean.
The swamp is not really interfering much, but the flooding does prevent the grass from thriving, so we had a large area of dirt/mud in that corner. The rock garden will facilitate drainage more effectively than soil would.
I wouldn’t necessarily be against a rain garden (had to Google it), but landscaper dude is pretty confident that he can make this work. We shall see.
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Yeah - I wouldn’t try to grow grass there, and would - instead - mulch it and plant shrubs/perennials that will tolerate wet.
I’ve lucked out and solved swampy spots by planting weeping willow trees and curly willow trees.
There are some low wet areas near my house that are home to many willows. Every few years the beavers come through and turn the grove of young willows into a field of pointed stakes suitable for the floor of a Burmese tiger trap.
Regarding the possibility of using non-perforated drain tiling to route the water all the way to the street, is the low spot in your yard below street level, making it impossible for the water to flow to the street at all?
Hmm… blueberry bog…
Nope, the street is lower than the swamp. I’m starting to think that would have been the way to go.
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Next storm please let us know how the fix worked!
I will. They keep telling us it’s going to rain, then nothing.
The news in on as I type this - they are saying showers tomorrow. We will see.
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So I see you’ve already spent lots of money on this contractor to fix a problem they themselves exacerbated. It appears your contractor is a moron and when – not if – this problem continues I surely hope that you do not hire them again.
I think there is some confusion about the terms used by your contractor and by some of the posters in this thread. Some clarification:
A French Drain is a buried perforated pipe that collects groundwater and, using gravity (the pipe is buried with a slight slope) transports that water somewhere where it won’t be a problem: out to the street, into a drainage ditch, into a storm sewer, or into a sump pit. It does not – repeat, does not, disperse water into the ground. For that you need a leach field like what septic systems use. These are usually huge (like, 5 or 6 feet wide by 3 or 4 feet deep by 50 feet long) trenches that are filled with gravel or extremely porous dirt (sand). A perforated pipe is laid in the trench and water that has already been collected is drained into the pipe wherein it then leaches out into the surrounding porous soil or gravel. This is overkill for a rainwater discharge system and other solutions are superior. See below.
A French drain is essentially the reverse of a leach field. In a heavy rain (or, in the case of my house, a very high water table) the ground becomes saturated with water and therefore any extra water has nowhere too go except run across the surface to the lowest point – in this case, the corner of your backyard. The French drain helps drain the soil so that water will flow down and through the soil rather than collecting on the surface. As noted the drainage end of the French drain is open to air so it can freely flow out.
A good French drain uses perforated PVC pipe rather than that flexible black garbage. The black flex pipe clogs easily, can’t really be cleaned out when it does clog, and deteriorates over time. PVC is the way to go. The perforations are placed at about 90 degrees to each other, holes facing down. The groundwater flows into the pipe and then, because the pipe is sloped, flows downhill and out the open end.
A dry well is a collection and dispersion device. It collects water from a French drain or downspout and then disperses it into the surrounding soil much like a leach field does. For this system to work properly the dry must 1) be placed in porous soil and 2) surrounded by several feel of loose stone to aid in draining and 3) placed somewhere the surrounding soil does not get saturated. A properly placed dry well will be placed in a hole ~3x the diameter of the dry well, with the extra space filled with loose gravel. Even then, as noted, it will only work if the water can eventually flow into the surrounding soil.
You are correct. The fact that the dry well is full of mud indicates improper intallation or a catastrophic failure of the well casing. A dry well full of mud is no better than the original soil. Since it’s only one day old, my money is on the former.
OP, I have the same problem you do: one corner of my back yard turns into a small lake during heavy rains, something that’s all to common here in western Oregon. I have street front property and the whole lot slopes gently toward the rear so that effectively the back corner is the lowest point on the lot. All the rain water collected on 8000 square feet collects in in one single spot. Because of this there is only one solution, one I haven’t done yet because it means tearing up a big chunk of the yard and digging a trench to the street and paying an electrician to come out and do some installation: put in a Sump Pit. I have an old sump pit already on my property but it’s in the wrong spot and I need to essentailly start over fresh, designing a drain system that will actually get rid of the water that collects on my property.
Fundamentally the problem is simple: rainwater cannot seep into the ground because the ground, like a dripping wet sponge, is already saturated to capacity. It simply cannot accept any more water thus the water sits on the surface. As rain continues to fall the surface water grows in volume and before long there’s a small lake where my yard should be.
You said that
::pulls out a twenty:: I bet you here and now this will not work. Rock like this is called riprap and it serves only one purpose: to limit erosion. Think of it this way: all the rain falling from the sky hits those rocks and then… what? It doesn’t disappear. It flows across and down the rock to the ground where it then does whatever it did before the rocks were in place, in your case sit there and create a lake. Riprap is used on river banks and lakefronts and ocean jetties to reduce the impact of water on the underlying soil and prevent said soil from washing away. It will do nothing to stop standing water from collecting.
Both those ideas, whatever they are, I’m certain will be expensive and not solve the problem as it appears that your contactor does not understand the concept of gravity.
Your contractor installed a dry well. A dry well will not work because the ground is already saturated – that’s why it floods. There’s nowhere for the water to flow to once it’s collected on my lawn, and that includes flowing down into the ground. So it just sits. You have the same problem. The water cannot be dispersed into the ground if the ground is already saturated. If I put a French drain in it would do me no good because that water that collects into the pipe needs to go somewhere and the only somewhere it can go is downhill. Since the only downhill place it can go is the flooded area where it’s already going, a French drain would be useful only if I could do something with the water once it gets to its discharge point. Since a drywell is a non-starter and I don’t have a handy drainage ditch or storm sewer to discharge a French drain into I have only one solution: a pump. I need an electrical sump pump in a basin physically similar to the dry well. Water would collect in the sump pit and then the pump would pump it out to the street. The discharge line would be solid PVC and running it next to the house’s foundation would be totally fine. (I saw upthread where your contractor didn’t like this idea. Discharge lines are solid pipe, not perforated, and running them next to or through or under the house would have no detrimental effect at all.) The nice thing about a sump pit is you can run several pipes into it. The one I have designed and will need to be installed someday probably sooner rather than later will sit in the corner of the yard and there will be two French drains running into it: one that collects water across the back of the yard and another that collects water along the side yard. They will meet at the sump pit at a 90-degree angle, both drains discharging into the pit. I will also bury two solid 4” PVC pipes to take water from the two rain gutters to the sump pit: rain gutter water will flow down the downspouts, into the 4” PVC, across the yard and finally into the sump pit. All this water will be collected in the pit – remember it’s actually a plastic barrel that collects the water and holds it – and then pumped out by the sump pump. Those pumps are usually rated for 600 GPM so even in the heaviest rains the pump will easily be able to handle the incoming water.
I think this is the solution you will eventually need. After figuring out what I need to address my standing water issue I found this YouTube video done by a professional drain contractor in North Carolina. He basically does what I had envisioned I needed and at the end of the video he does a walkthrough during a heavy rainstorm showing how the system works. I’m convinced it’s the only way to address my problem.
That video was interesting. A couple of things surprised me though:
The houses in that street were allowed to pump water from all the roofs and land drains straight out onto the street.
The neighbours didn’t seem to be concerned about excess water being dumped in their yards or having water dumped into theirs.
The contractor, who clearly knew his job, put in several small sumps with powerful pumps. I would have thought that a much (very much) larger sump would have been a better solution, allowing the water to be pumped out over a longer time.
Finally got some big rain overnight. No signs of flooding.
Likely much more rain coming, may be severe.
Fingers are crossed.
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OK, back-to-back gulley-washers (Dad’s term) on two consecutive nights with zero flooding.
I am thinking it is working.
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Well it looks like @Lancia owes you a twenty in Monopoly money!
I’m still confused as to why it worked though. Maybe the rocks on top effective enlarged the volume that can serve as the dry well?
Thanks for the follow up.
I dunno. I’m not sure how deep the rocks go, but I know that rocks facilitate drainage more effectively than soil does.
And it’s not like the water has no place to go - there is the underground barrel (dry well, I guess) full of gravel and connected to two lengths of perforated pipe that are nestled in their own gravel beds.
I’m not demanding the Monopoly money just yet, I feel that would jinx it. 
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Well I am happy to pay up if I’m wrong, but I’m still confused as to how the solution is working. I’m curious if it still functions after a season or two of rain.
@Lancia, please clarify. Are you surprised about the initial solution, the tweak (adding the gravel bed corner), or both?
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Both, and maybe confused as well. What you described in your OP was a classic French drain system: buried perforated pipes that take water that collect on the surface or immediately under the surface and transport it somewhere where it won’t be a problem. In your case, a dry well. You also said the after the first big rain you noticed the dry well was full of mud. This should not be. Landscape fabric is supposed placed around both the French drain pipe and the dry well to prevent this. Mud means either the landscape fabric was not placed where it should have been, incorrect fabric was used, or the dry well casing failed and allowed mud from the surrounding soil to come in. Regardless, the whole point of a dry well is store water temporarily and then allow it to seep out naturally. It can only do this if a) the dry well is empty when water starts coming in and b) the area surrounding the dry well is gravel or sand, not soil. If the dry well is full of mud then it’s no better than dumping the water directly back into the ground at the same rate it was collected, which is what the whole system is designed to avoid.
Further, as I noted in my long post upthread, French drains collect water, not disperse it. It sounds like your landscaper made a leach field that runs away from the dry well. If it works, well, I guess it works but it does surprise me – leach fields are massive (long, wide, and deep) because, like a dry well, it needs lots of cubic footage to get the water to drain out rather than simply collect in the pipe.
And I still maintain that the rock garden itself will / would not contribute to reduced flooding. The rain that falls on the rocks flows down the rocks and onto the ground and then… what? Unless it can drain away it will collect in a puddle/pool/lake. It’s not like the rocks are absorbent. The fact that it’s now draining likely has nothing to do with the new rock garden. In fact since soil absorbs water putting a big dirt mound rather than a rock pile would have likely done marginally more good – or at least until it washed away.
I’m glad that it’s working but I guess I just can’t wrap my head around the why of it working. It seems to me that the contractor did nothing to actually fix the problem. But obviously there’s something here that I’m missing if it’s working.
