Just about every project that I look at has a drainage problem. In the valley we have the perfect combination of heavy, poor draining soils, lots and lots of rain, also poor design by either the city or the builder/developer that built your home or designed the community that you live in. Unhealthy plants and lawns suffer the most from compact, heavy clay soils, much of the problem can be traced to poor drainage. There are many different ways to solve drainage problems from the traditional french drain to rock wells to the eco friendly Rain Garden.
French Drain - not sure where the name came from. It consists mainly of a trench and a pipe covered with drain rock leading to either a low spot or a pipe that can take it to either a storm drain, low land area or Rain Garden. This type of drain is best left uncovered by dirt, leaving the round rock exposed to pull water from nearby areas into the lowest part of the pipe or drain. I don't like using a sock around the pipe, unless the area is a slow drain off area, the sock will slow down the time it takes for water to percolate into the pipe, its better to oversize the pipe if you're worried about silting in the pipe over time.
Round rock sump - This type of drain works ok when there is no place to take the water. Dig out a hole, run a pipe or french drain into the hole, fill the hole with round rock, eventually the water will percolate through the soil and drain out the entire area.
Perimeter drains - I like these drains around lawns to separate shrub beds. Most of the time a shrub bed is rounded up and will drain off down into the lawn. This creates problems especially when the shrubs are watered in the summer as well as the lawn. The water running off the bed is double watering the lawn, this can lead to over saturation of the lawn inviting the crane fly larva to lay eggs in the soil. It is best to try to create french drains along the edges, running the drains away from the lawn areas. Mainly creating a lower "bottom" point in the landscape so that water drops below the root zone allowing roots to penetrate deeper and dry out as needed.
Roof gutter drains - Many times I see improperly maintained roof gutter drains, they dump down into the landscape flooding out not only the foundation of the house but the plants and grass as well. If you don't have roof gutter drains install them, move the water away from the foundation of the house and the landscape, preferably to the street or a low spot as far away as possible. In some cases it is difficult to get them away from the house and you have to get creative sometimes installing pumps, rain barrels, ect, the main thing is to move the water away.
Sump pumps - pumps are expensive but sometimes the only alternative. Usually they are used under houses or in basements where water levels are high and drainage is not available. We can be very creative with pumps and basically no situation is beyond drainage if you are willing to install a pump system in the landscape to remove the water.
Rain Gardens - Creativity is the word here! Mainly creating a low drainage area were native plants can thrive. I like to combine round rock, large and small rocks, sandy draining soils, native grasses and ground covers that will naturally handle the water in winter and dry weather in the summer.
Rain barrels - I like this idea, you can get very creative in the designs of these types of drains.
- They can be used for roof gutter drainage and can be set above ground or under ground.
- They could be used to water the plants in the summer with under ground storage (cistern) and a drip sprinkler system.
- I think that eventually this type of drain will be standard practice especially in the SW were water is scarce.
The main thing with drainage is just fix it. Call a professional with many completed projects and references and have them design and install a system for you. It will most likely be the very best investment into your landscape that you can make.