A deck allows you to relax and entertain outside, but without proper drainage, it's possible for water to pool underneath. This can create a breeding ground for mosquitoes, mold and bacteria. If you have water standing under your deck after the rain, choose a drainage system that works for you.
Sloping Bricks or Cement
The soil under your deck will soak up as much water as it can, but when it becomes saturated, the water pools. Prevent this by laying bricks or pouring cement under the deck. This area should slope away from your home, allowing the water to easily run off into the rest of your yard.
A dry well is a large area that collects and stores water, slowly dispersing it into the ground. You can purchase a pre-made dry well or create your own by digging a hole, lining it with landscape fabric and filling it with crushed rocks. You can then set up gutters and pipes to collect the water and divert it to the dry well.
Under-Deck Drainage System
Under-deck drainage systems are an easy solution to the water pooling under your deck. The idea is to create a slanted sub-layer underneath the deck that collects the water and diverts it to another area of your choosing. Many companies make products to do this.
A French drain creates sloping areas to allow the water to easily move from under the deck without the utilitarian look of a cement slab. It consists of a series of trenches and pipes sloped to direct the water where you want it to go, then covered by small rocks to allow better drainage into the system.