What better time to take advantage of the rain and set up a rain water harvesting tank? Water is a precious resource these days, many experience drought yet other areas are tired of seeing the rain. How can we use rain water harvesting to help clients?
Don’t lose the opportunity to save your client water and money. Instead of allowing runoff water to flow from lawns into streams, rivers, then ocean:, collect it! As a landscape architect, you can build a RWH system in your own yard to become more familiar. Doing so will make it easier to design a system for your clients that are concerned with conservation.
Our very own Debbie Bedway took on this challenge in her own garden. Check out her progress:
According to the Ohio Irrigation Association, virtually every house and commercial building already possesses roofing, gutters and downspouts. The water catchment system simply collects the rainwater that now flows out of the spouts and instead stores it for use at a later date.
The Basic Setup
You likely will not be the person to install a rain water system at a client, but it is good to know what you can offer. There are several different options for storing rainwater: above-ground storage tanks, below-ground cisterns, or downspouts directed to bioswales. Smaller systems (that capture less than a hundred gallons) can use rain barrels for storage. A simple residential project typically runs between $1,500 and $5,000, depending on a variety of factors, such as size and excavation costs.
Whatever option you choose, a pump may be required to release the water when it’s ready to be used. Most pumps on residential systems are between one-third and one horsepower. That amount of power is sufficient to pressurize the water for either spray or drip irrigation. The pump can be activated manually, or a controller can be used to automate the rainwater flow into the irrigation system.
A couple of important considerations:
- Sanitation should be the first consideration. At the very least, a screen should be placed in the gutter over the downspout. This will keep out large particulate matter, large solids and leaves.
- Storage tanks must be properly sealed against pests and bacteria; otherwise, the water inside can become toxic.
- Every storage tank needs to have an overflow device to prevent backup in heavy-rain situations.
- The overflow device should be fitted with a flapper valve that will close up immediately after excess water has stopped flowing out. This will keep vermin from crawling up the spout.
An Attractive Option
For property owners, either yourself or your clients, who find traditional storage units unattractive, more aesthetically-pleasing options are available. For instance, Aquascape, an Illinois-based company, offers its “RainXchange” system, which combines a recirculating, decorative water feature with an underground storage basin.
According to Irrigation & Green Industry magazine, RainXchange offers the same functionality of other storage systems. Specifically, “It makes use of modular storage basins, stackable blocks that are somewhere between milk crates and Legos, which can be arranged in different shapes to fit a variety of application settings. They sit inside a rubber membrane to form a single, water-tight unit underground.”
Contractors can install the RainXchange system under turf grass. An increasingly common option is to install the system underneath a patio made of permeable pavers. According to Ed Beaulieu, director of field research for Aquascape, “This way, the pavers act as a catchment area that prefilters the rainwater before it enters the blocks. It’s very, very efficient.”