Passive Rainwater Capture (PRC) System

For Ornamental Plant Use

Senior Design Project (Spring 2005)

University of Texas at El Paso

Department of Civil Engineering

What is Passive Rainwater Capture?

Passive Rainwater Capture is based on the principle of collecting rainfall from capture areas such as roofs, parking lots, and driveways for landscape use.  The captured water is stored in the soil utilizing the differential between the water content at field capacity and the water content at the wilting point. Passive rainwater capture reduces problems associated with storm water flow and saves water and costs associated with landscape watering.

Will it work in El Paso?

Yes!  Naturally occurring passive rainwater capture systems are found in various parts of the city.  In the vicinity of the campus of the University of Texas at El Paso, natural systems are found alongside parking lots and the adjacent Interstate Highway 10 roadway.  If this vegetation survives with no additional irrigation, can the principle be applied to residential and/or commercial use?  Click HERE to view some of these natural systems.

How much rain does El Paso get?

The annual average rainfall is 9.43 inches. Click HERE to view the comparative analysis and graphs created to establish trends. 

What kind of plants can be used?

Native plants categorized as drought resistant or low water use survive best.  Click HERE to see a plant list.

How is the water stored?

This system utilizes the water-holding capacity of the soil to store the water based on the soil’s texture. Click HERE for more information on field capacity and wilting point.

What are the benefits of a Passive Rainwater System?

A passive system:

a) saves precious water resources

b) reduces problematic storm runoff

c) lowers costs

d) provides a beautiful environment

e) reduces stormwater systems

f) can be used in multiple applications

Can I see a detailed design example?

Yes, click HERE to see an example design for a single home residence. The design concept will work for commercial or industrial sites, residential subdivisions, and government sites such as rest areas along highways.