How To Analyze Your Water Drainage Problems

 

Normal drainage problems start during a rain storm and can last for a few days afterward. They usually fit one of these 3 memorably named categories:

1. Lake Downspout
2. Soggy Lawn Swamp
3. Rainy River

There is a 4th category that we will not be tackling in this guide, the Eternal Wet Zone. This is a soggy bit of landscape that never seems to dry up, even when it has not rained for weeks. It is probably a spring, an area of unusually high water table, or a leaking water or sewer pipe. All of these situations call for professional assistance. Don't start digging into an area that may be a little spring, or it is likely to become a BIG spring. Here is an article that will give you a little insight on dealing with springs.

Installing a drain system yourself is probably going to involve some expense for plastic drain pipe (still called drain tile by some - I will use both terms), much gravel, and a lot of digging. Before you start spending you time and treasure, let's figure out WHY your yard, lawn or garden has a drainage problem, and then we will figure out how to best FIX it. That means going out in the next rain storm and getting a little wet...

Before the next rain storm you should do these few tasks. First, round up a dozen or two wooden stakes, a hammer, a pencil or two, and a rain poncho or umbrella. Next make a sketch - on something fairly water proof - of the portion of your yard that has the drainage problem (I like to use a scrap of plywood). Lastly check your gutters and downspouts to make sure they are not plugged and that the downspouts are intact. You may want to have others in your household read this guide also so they can do the discovery task for you if you are not home during the next big rain storm.

Shortly after the rain storm starts head outside and watch for the occurrence of our 3 memorably named water drainage problems; Lake Downspout, the Soggy Lawn Swamp, and the Rainy River.

 

The first drain problem to show up is usually Lake Downspout. Try to figure out why rain water is building up near your gutter downspout. Is the ground next to the house tilted back towards the house so the water can not flow away? Does the problem downspout have a whole lot more water coming out of it than other nearby downspouts? Are there two gutter downspouts fairly near each other with a lake between them?

Mark the center of any Lake Downspout with a stake with the number 1 written on it. Note if the soil is fairly soupy so the stake slides right in, or if it takes firm steady pressure to push the stake in (indicates clay soil), or if you have to hammer the stake through a hard crust (indicates surface compaction). Make notes on your plywood sketch of any clues you discover.

 

The next drainage problem to pop up is usually the Soggy Lawn Swamp, though in your yard it may be better called the Soggy Garden Swamp, the Under Deck Flood, or some other soggy area I will let you name. Slosh on out to the middle of each one and stick a stake in with the number 2 written on it. Again note how hard it is to push the stake in.

Mark these places on your sketch and then look around to try to find where the water is coming from. Is a Lake Downspout feeding your swamp? Does the swamp show up as a broad low area in an otherwise flat lawn? Is your swamp the pathway between raised flower or garden beds? Or does it fill the area above or below a retaining wall? Is your swamp backed up against your foundation wall? Is it stretched across a dip in your driveway or along the edge of a patio? Take lots of notes and mark all these areas with your #2 stakes.

 

After awhile it will be time for the Rainy River to start flowing (if you are unlucky enough to have one). Sketch its path and mark it with stakes with a 3 written on them, usually one at the river's beginning, one in the middle, and one at it's end. Again note how easy or hard it is to put the stakes in. Try to figure out where the river originates and why it flows where it does. Does the river begin on your property or your neighbors? What is feeding the river? Is it flowing across an area that causes any problems for you? Is there a natural depression or swale that the river follows? Does it drain to a ditch, the street, or just flow into another Soggy Lawn Swamp? If it flows into a Soggy Lawn Swamp, does the swamp keep growing or does it stay the same size? (in other words, can it handle the additional flow?)

 

Wander around a little longer and see if anything changes much, and if any other insights come to mind. Then go inside, dry off, have a cup of coffee, and try to figure out how you are going to explain your strange behavior to the neighbors.

Once the rain stops head back outside with your pencil and sketch. Take notes on which areas disappear first. Normally the Lake Downspouts and the Rainy Rivers will disappear first, and the Swamps will hang around the longest - but not always. Note on your sketch the places that disappear quickly. Also mark the ones that are very slow to disappear, like more than 8 hours. This TIMING information will be useful in setting priorities of which drainage problems to tackle first.

So now you have information on where your drainage problems occur, some clues as to why they occur, and information on how severe they are (that's the drain time information).

Next in Step 2 "How To Design a Drainage System" we will figure out how to solve these problems