An ideal lawn is based upon the concept of having more or less ideal soil supporting that lawn. Until your soil is in good health, everything else is a waste of time, money and effort.
On the other hand, if you have a good healthy soil, you don't have to fertilize your lawn as often, you don't have to use as much pesticides, and you'll have less lawn disease infestations.
To put your soil into shape, you must first start with how water flows across the lawn when it rains. Almost every place where you can consider growing turf grass will get deluged with rain from time to time. How you property handles those sudden down pours will tell you much about the health of your soil.
The best soil for lawns is friable loam. This is especially true for cool season grasses. With this type of soil, most of the water will soak in rather quickly and pass downward into the soil's natural sub-surface drainage channels. Some will flow outward over the surface but will be gone long before it reaches the edge of the lawn. Much of it will be blotted up by spongy elements in the soil and held for use by the grass. There will be very little run-off into the streets.
Sandy soil's the water also disappears quickly, but instead of being soaked up or trapped underground, much of it will pass through the sandy soil before the grass roots can absorb it.
Heavy clay soils, particularly in level areas, the water may remain on top for a long time, often until it disappears by evaporation. This suffocates a lawns roots, kills of beneficial microbes, and further compacts the soil increasing the standing water cycle.
If the land slopes, the water runs off without penetrating. If the soil is heavy in clay but contains some organic matter (such as might be the case where sod has been laid on top of excavated subsoil such as a housing development). Some water will gradually soak in, but so slowly that a substantial part of it will be lost through evaporation.
By studying how the water drains from your property you can see the reason why the first important step in lawn-making is doing a simple site analysis to determine the grade of the land and related factors.
Part of the study concerns the slope of the land— the natural path of runoff water from rains too heavy for the soil to blot up at once. First attention, however, is given to a phase of lawn-making which 95 out of a 100 homeowners never consider at all— underground drainage.
All too often, the lawn-maker takes drainage for granted, if he even thinks about it at all. Even if assuring proper grade and drainage means that you must lose a season in establishing a permanent lawn, it still will pay you to do the work right. And that means fixing the soil first so that water neither stands or drains too fast. It means creating a good soil base in which to grow grass.
If you don't create a good soil base, then everything else you do is wasting time, effort and money by just putting a band-aide on something that requires a tourniquet.