Catchment areas can include soil surfaces, roofs, roads, and sidewalks. Think about where rainfall already accumulates on your property.

The distribution system refers to how the water is directed to flow to the end point, or landscape holding area. These can include downspouts, contoured channels, rain chains, French drains etc.

There are endless ways to get creative when designing a holding area for runoff. The following techniques can help soak water into the ground and reduce runoff.

Berm and Basin. Here is an example of a berm and basin technique. This requires using soil to create hills and small valleys in the landscape for rainwater collecting. It works best with a sloped land with a ratio of 3:1 – for every horizontal run of 3, there is a vertical rise of 1.

Swales are similar to the berm and basin technique but swales are shallow, with the goal being to slow the water down and direct it to a new location within the landscape. Swales aren’t trying to get all the water to sink down in one area like basins do.

Sediment traps placed on the edge of a landscape can trap sediment in a designated area, allowing water to travel more smoothly throughout the landscape.

Infiltration basins. These are small basins for landscapes where water is directed to collect and go into the ground over time. They usually are wide and flat at the bottom.

Help your trees soak up more rainwater by creating water basins at the canopy line of the tree. A water basin is a ring around the canopy of the tree that is more shallow than the surrounding soil so that water will collect there and slowly soak into the soil. Doing this for your trees not only cuts down on potable water you’ll need to use but also encourages the roots of the trees to grow out and anchor the tree.

Mulch is an organic material like wood chips that can be used at the bottom of basins to help absorb and retain water. It helps reduce evaporation and gives water time to get into the soil. Mulch is also used to mitigate the urban heat island effect by lowering the surface temperature, enhancing percolation, and retaining soil moisture.

Make sure you do a soil drainage test in areas that you want to harvest rainwater so that you don’t end up with sitting water after a rain event. Here are the steps for a soil drainage test:

1. 1. Dig a circular hole about one foot deep and one foot wide.
   2. Fill the hole with water. If the water soaks into the soil quickly, continue to fill it until it stays full for a bit.
   3. Wait 12 hours and then fill the hole again. The water should drain in about 2-3 hours. If not, the soil is not well draining.

Secure a tarp – either from trees in your landscape or stable posts/poles – so that the center of the tarp sags lower than the four corners. Cut a hole in the lowest point of the tarp and place a container beneath it to collect the water.

Create a V-shaped structure by bending a flat piece of metal or attaching two flat pieces of metal or wood together, making sure any seams are completely sealed to avoid leakage. Orient the structure so that one end sits at a higher point than the other, directing the flow of water down the seam to the lowest point. Place a collection container at the lowest point.

Observe the drip patterns from the edges of your roof, sheds/outdoor storage, and fencing next time it rains. Place containers on the ground underneath the areas where the most rain flows. Consider installing diverters with drainage pipes to direct the flow.

The base for your tank should be flat/level, clean, and made up of a single non-abrasive surface type to prevent development of pressure points (from rocks and/or transitions between surfaces) on the bottom of the container. If placing your storage container on a surface of sand, clay, dirt, or gravel, make sure to incorporate additional support beneath the surface (i.e., concrete, rocks, lumber) to prevent erosion during storms and heavy rains.

Tanks should be light proof to prevent algae growth and UV resistant to prevent sun damage.

Use rubberized paint for additional light/sun protection and to turn your storage container into a personalized art piece in your landscape!

Look for a rain head screen and air relief vent that excludes light to further prevent algae growth.

Make sure your rain head, inlet, and overflow screens/flaps are insect-proof to prevent mosquitoes and smaller insects from entering the water system.

Install your rain head screen at a height you can easily see and access so you can inspect and/or clean it as needed before, during, and after storms.

Clean the roof and gutters before storms to reduce the amount of build up on the rain head screen during storms.

Place tanks so that they serve a dual purpose (e.g., acting as a windbreak or privacy screen). Water quality can be impacted by storage temperatures. Choose a shaded location for your tank to reduce temperatures and preserve water quality. Consider directing overflow from your tank to passive earthworks that can utilize the water to support shade trees/shrubs. Wherever you place your tank, make sure you can walk all the way around it to monitor for and/or fix any leaks.