The Future of WaterTom Kundrat CIC, CLIA

Product Manager

The world’s water crisis

Widespread drought conditions

Increasing regulation

New Green Codes requiring use of non-potable and/or reclaimed water

Stronger regulation in particular markets US: California, Florida, Texas, Arizona

Worldwide: Australia, Israel, Spain

Anticipate similar levels of regulation across the US

Residential Water Bill Increases (Past 12 Years)

• Atlanta, GA 233%

• San Francisco, CA 211%

• Wilmington, DE 200%

• Philadelphia, PA 164%

• Portland, OR 161%

Increasing Water Costs

Emerging irrigation technologies

Continued purple identification Manufacturer investments in reclaimed-

resistant materials Valves

Spray heads

Expansion of irrigation systems to include water harvesting equipment

Innovation in intelligent control systems

Non-Potable Water for use in Irrigation

SystemsSources, Definitions and Technical Considerations

Lance Sweeney, ASICPresident

Sweeney + Associates, Inc.

Summary

Potable Water, that which is suitable to drink, is becoming an increasingly precious commodity. In some areas, it is illegal to use potable water to irrigate the landscape. Many project owners, Landscape Architects, and Irrigation Designers are looking at non-potable water sources to replace, or reduce, the dependency on potable water.

The use of non-potable water is not without its challenges. These include availability, reliability, agency requirements, water quality, plant suitability, and specialty equipment. There may also be competition for these non-potable water sources from other water users on the project. Many projects use non-potable water for such uses as flushing toilets and filling cooling towers.

Non-potable water may be the right choice for your landscape irrigation system, this webinar will help you make that decision.

Non-Potable Water Sources

Agency Provided Non-Potable Water Recycled / Reclaimed Water

Project Provided Non-Potable Water Rainwater

Storm Water

Gray Water

Air Conditioner Condensate

Cooling Tower Blow-down

On Site Sewerage Treatment

Raw Water

Desalination

Recycled / Reclaimed Water

Treated and delivered to site by local agency.

May be required for use by the local agency.

Water rates might be lower than potable water or even subsidized.

Generally of high quality, but can have high salt and chlorine levels.

Not necessarily well suited for all plant materials.

Local agency and health department rules vary by state, county and city.

Some agencies require yearly inspections of systems.

Purple color coded pipe, equipment, and valve boxes required.

Backflow prevention devices may be required.

Signage required.

No sprinkler overspray allowed.

May be delivered in a lower water pressure than potable supply.

Rainwater

Rainwater is collected off of roofs and other hard surfaces.

Rainwater stored in cisterns below or above grade and in buildings.

Generally clean, but can pick up contaminants off the roof.

Make-up water may require an air gap between potable source and storage.

First flush diverters and filtration required.

Some agencies require use within 48 hours.

Stored rainwater can become septic quickly unless treated.

Can have a long Return On Investment (ROI), depending on region.

Best suited in regions where rain occurs during summer growing season.

In ground systems can be designed by Landscape Architects.

Little agency involvement, but they are catching up!

Rainwater

Rainwater is collected off of roofs and other hard surfaces.

Rainwater stored in cisterns below grade, above grade and in buildings.

Generally clean, but picks up contaminants on roof.

First Flush diverters and filtration required.

Make-up water may require an air gap between potable source and storage.

Some agencies require use within 48 hours.

Stored rainwater can become septic quickly unless treated.

Can have a long Return On Investment (ROI).

Best suited in regions where rain occurs during summer growing season.

In ground systems can be designed by Landscape Architects, systems within buildings require design by MEP Engineers.

Little agency involvement, but they are catching up!

Storm Water

Storm water is collected off of all surfaces of the project.

Storm water stored in cisterns below grade and in buildings.

Not as clean as rainwater as the collection surface is varied.

Make-up water may require an air gap between potable source and storage.

Some agencies require use within 48 hours.

Stored storm water can become septic quickly unless treated.

ROI may be shorter as it offsets other storm water requirements.

Best suited in regions where rain occurs during summer growing season.

Generally designed by Civil Engineers.

Much more agency involvement.

Gray Water

Gray water is diverted from sinks, showers and/or washing machines.

Gray water stored in cisterns below grade and in buildings.

Not a clean source of water and it can be hazardous. Gray water contains whatever is sent down the sink or drain.

Soaps and chemicals can harm plants or soils. E-coli bacteria can occur from human contact.

Gray water may be treated or untreated.

Simple leach field type systems are very common on residences.

Some agencies do not allow above ground application.

Large commercial systems may require a permit, but residential units may not.

Make-up water must have an air gap between potable source and storage.

Generally required to be used within 24 hours of collection.

Depending on complexity, may have a long ROI.

Little agency involvement for small residential systems, more involved for large systems.

Air Conditioner Condensate

AC condensate is the water collected off of cooling coils of an air conditioner.

Usually a waste water product, so its use may offer multiple benefits.

Can be coupled with other non-potable water collection strategies.

AC condensate stored in cisterns below grade, above grade and in buildings.

Very clean water source, basically distilled water.

Make-up water may require an air gap between potable source and storage.

Some agencies require use within 48 hours.

Stored condensate can become septic quickly unless treated.

Long ROI, but the ROI can be reduced if coupled with other alternative water sources.

Best suited in warm, humid regions.

Requires involvement of the MEP Engineer.

Some agency involvement.

Cooling Tower Blow-down

Blow-down water is the used water and wash down water from cooling towers.

Usually a waste water product, so its use may offer multiple benefits.

Can be coupled with other non-potable water collection strategies.

Blow-down water stored in cisterns below grade, above grade and in buildings.

Not a clean or suitable water source unless processed.

Several treatment processes available. Substantial installation and maintenance costs.

Make-up water may require an air gap between potable source and storage.

Some agencies require use within 48 hours.

Stored blow-down water can become septic quickly unless treated.

Long ROI, but the ROI can be reduced if coupled with other alternative water sources.

Requires involvement of the MEP Engineer.

Some agency involvement.

On Site Sewerage Treatment

Small sewer treatment plant suitable for a single project.

Often used in remote sites or areas without suitable infrastructure.

Water provided can be similar to recycled / reclaimed water.

Requirements are the same as recycled / reclaimed water.

Until project is populated, product water may be limited.

Make-up water may require an air gap between potable source and storage.

Complicated ROI as few projects use these systems for just irrigation need.

Requires involvement of the Civil and MEP Engineers.

Substantial agency involvement.

Raw Water

Water from wells, lakes, ponds, rivers or canals.

Water sources may be self replenishing.

Water may be free of cost, other than pumping costs.

Quality varies by source.

Pumps, filters and injection systems required.

Depending on water cost, equipment required, electricity costs, and maintenance the use of raw water could have a short or long ROI.

Most systems can be designed by a Landscape Architect.

Some agency involvement.

Desalination

The conversion of salt water into fresh water.

Sources include the ocean, raw water sources or wells.

Several methods available. Reverse osmosis it the most popular for project specific systems.

Resulting water quality can be very high.

Process creates a salt brine that must be disposed appropriately.

R.O. equipment is expensive and the energy costs are high.

Most often used in areas where no potable supply is available. Often the desalination plant is set up to provide potable water to the project and the irrigation water is a blend of the potable water and the reject water.

Lots of controversy in this process due to salt disposal challenges.

Conclusions

There are many viable alternatives to the use of potable water for the irrigation of landscapes. Most projects have access to alternative water sources that can offset the use or completely eliminate the use of potable water.

The benefits of each alternative sources vary with each project. The cost, return on investment, health concerns, and maintenance issues should be considered prior to the use of these alternative sources.

The water quality of the alternative source should be considered when selecting the landscape plants for the project. The irrigation design should incorporate all required design methods and equipment to effectively use the alternative water sources.

Questions