Experts, more trouble around my home, I know you're sick of me already ;-) Had I known I would end up with so many problems, I would have moved into a tipi :) Most of my yard up front is below the street and sidewalk, about 2 inches. Towards the other end there is a pitch, roughly 1-2% like 6" down after approx. 30 ft but the pool is in the middle hence I need to go around it with pipes to route gutter rain water to the street. Clay soil and lots of thunderstorms in the summer. Tropical storms are especially worrying. What I need is drainage during severe storms. There are several areas where the water gets stuck. I dug a trench going around the pool with a little pitch to it. It actually works but if a little dirt piles up, the flow stops. How can we fix this problem? I was thinking we could order a few truckloads of soil and fill the entire lot until we have the pitch we need...

When you say "pool" are you talking about a pool of water or a "cement pond" for swimming in?

Collecting water with perforated pipes and directing it (downhill) to a lower location "daylight" is the best way to deal with clay soil and water problems. Typically, a slope of 1/4" per foot is recommended (that is about a 2% grade), but if you are good with the grade and use rigid pipe, you can easily go with 1/8" per foot (1%) or even less, like 1/2% and still get water moving. If there is simply no low spot you can get to that would afford a slope, then you have two options remaining.

1) Create your own low spot in the form of a sump or a dry well. If the thickness of your clay soil is finite, you might be able to get a dry well deep enough to reach a permeable layer. Just fill up the "well" with rocks or drain rock and direct the water you collect there. If you can't get through the clay, the dry well becomes a sump which is simply a collection point for actively pumping the water to a place it can drain away. That will require electricity and maintenance of the sump forevermore.

2) You can regrade or recontour your ground. That entails removing any topsoil you might have and reserving it for use later. Then, you recontour your impermeable clay soil by scraping it up to create a low spot near where you want the drainage to go and filling to create high spots. As you have probably already noticed, if you have very fine clay soil, even a rise of 1" can hold up an equivalent amount of water, creating wet spots. The grade has to be perfect, with no intervening low spots to collect water. When you are done, you can add shallow channels to further ensure the flow of water towards the edges, or, better yet, dig shallow french drains, lining them with silt barrier and setting perfed pipe surrounded by gravel. Now, it's time to backfill using the reserved topsoil. If the topsoil is native, to the clay area, it won't be a whole lot better than what you have below, so you want to mix it with utility sand to make it more permeable. Mix it 1:1 with sand or even 2:1 if it is very dense. You can also import good topsoil if you need more. This layer needs to be a minimum of 9" - 12" deep over your clay subsoil surface. You can take care of spans of up to about 15'-20' with this method. If you have larger distances to cover, you will have to use the pipe and french drains attentively.

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