I don't know what the laws are where you are, but where I live you are not allowed to channel water to someone else's property. It must exit your own property to the street. I agree with Yardvaark. It sounds like you need to research where the city planners designed the water to go and find out why its not going there. Its not hard to find that info. The city should be able to give you the development plan for your subdivision. Our city worked with us to help us solve the problem we had. I was told that just after the subdivision was built some neighbors further up the hill from us had similar issues to you. The city had to come in and build a storm drain through at least 2 of the lots to solve the issue for them. If you were not having these issues before your neighbor built his pool and garage then it sounds like you need to bring the issue up and demand it be solved. If it had happened to us and the city and homeowner weren't helpful in solving the problem we'd be suing both of them for not addressing the issue of drainage and recouping the cost of having to pump all that water out. In my son's old neighborhood the one house on the corner that was the lowest and kept getting flooded year after year was finally purchased by the city, torn down and a small park sits there now. But it took a long time for that to happen. I don't know for a fact, but I suspect law suits were involved. - In the link below I show how we solved our problem. But we really didn't have much issue with neighbors' lots draining into ours it was that our lot wasn't graded correctly in the first place and the water had no outlet to exit our property. Good Luck and please report back what happens. Here is a link that might be useful: Back yard drainage

We have a drainage problem in our rental too, and we're also cursed with clay. From my experience, changing the grade makes all the difference. But be careful that your efforts to buid up the low spot don't accidentally redirect the water into the garden beds. It might be more useful to build up an area closer to the house, and dig a sort of shallow, inclined drainage ditch from the low spot to the drainage creek - intentionally directing the water between the garden beds so it won't flood into them. As for collecting the water, you could certainly put some barrels under the spots where the water flows off the roof. But whatever you do, make sure the drainage situation is adequately resolved before you put in many plants. I lost four plants to poor drainage this winter, and almost lost a fifth - my evergreen coffeeberry lost almost all its leaves, and I'm still waiting to see whether it will recover. Here is a link that might be useful: pictures of my drainage ditch

I have one of each as well as a very handy husband. this is an excellent combination! The external pump is a ? is it a Sequel? 750, and it's ultra quiet. It's at the far side of the pond, there are a few plants in front of it, and I only hear it when I walk around to the far side of the pond. We have a double settling chamber in front of it, which catches everything and has an easy valve for cleaning. Much recommended! It's all ground level, so the pump uses hardly any energy. The submersible is a small one on the skimmer. That one zooms softly, but it's small, so no issue. Taking the filter sponge out of the skimmer is messy, but because it's at the surface it's not hard to do. I always switch the little pump off for cleaning (daily in spring and fall), but even so, after reassembling the sponge and the leaf basket, little bits of stuff often get into the pump or through the pump to the spitters, where it clogs the spitter outlet. We never have anything get stuck in the external pump. DH is the one who brings the external pump in for the winter and puts it back outside in spring. Our winter cold would damage the external pump. We also bring the little internal pump in, since it's at the surface. If we had a big submersible at the bottom of the pond, we'd be able to leave it in the water (although not running) in the winter. :) Mary

But how much travel does it have on it's float valve, I can assume it's a vertical activator? My pedestal sump pump has a long travel such that it only runs about once/twice a minute during the heaviest of leakage. A small submersible one would be running ever 10 seconds or so on/off/on/off! I have not heard of being able to or anybody macguyvering the switch to allow it to run less but pump more.. I have a sump well that is about 15" diameter and about 20" deep. Your sump must be 3500gph (not 35000 gpm :-) ) and decreasing as your head height increases. Of course, many submersible pumps are twice as much as pedestal ones and mine has been here since '99 according to a sticker I found on it. Jay