WATER CONSERVING TECHNOLOGY OPTIONS FOR INSTALLATION USE

1. WATER CONSERVING TECHNOLOGY OPTIONS FOR INSTALLATION USE Richard Scholze and Annette Stumpf U.S. Army Corps of Engineers ERDC-CERL Champaign, IL

2. Water Conservation Why Do It? Delay or Avoid Expensive Water Supply and Wastewater Treatment Capital Projects Helps Protect Fundamental Natural Resources Through Ecosystem Protection, Protect Current Quality of Life and Provide for Future Generations Minimize Effects of Drought

3. Federal Sector Executive Order 13123 Requirements Water Management Plan Implementation of FEMP BMPs

4. Selected Conservation Opportunities • Domestic Use • Administrative/Commercial/Institutional

5. Current Lowflow Designs Much Better Dual Flush Toilets Waterless Urinals Toilets

6. Dual Flush Toilet

7. Only Recently Actively Marketed in U.S. 4 New Manufacturers in 2004, Others Watching Marketplace Costs Becoming Competitive Do They Save water? 3 Study Summary 20-30% Savings in Water Weighted Average Flush 1.1 to 1.3 gpf vs 1.6 Customer Satisfaction Positive, Liked Option Advantage – Seldom Clogs Disadvantage – Smaller Water Spot, Possible Streaking Payback - 8.5 Years for $300 Toilet, 10 Flushes/day, Combined W/WW Cost of $3.79/1000 gallons Dual Flush Toilet Fixtures

8. Waterless Urinals

9. Becoming Widespread (Thousands in Use) Several Manufacturers Focus on Non-Residential Installations Concern Over Proper Maintenance Ex. Presidio of Monterey 173 Urinals Replaced – Classrooms, Administrative and Recreational Facilities in 48 Buildings Expected Savings - 11,500 gal/day or 3 million gallons per year Waterless Urinals

10. Food Service • Pre-Rinse Spray Valves • SOMAT System • Boilerless Food Steamers • Air-cooled Icemakers • Water Conserving Dishwashers

11. Pre-Rinse Spray Valves Typical Restaurant/Food Service – Up to 50% of Dishwashing Water Consumed by Pre-rinse Spray Valve to Remove Food From Dishware, Utensils and Pans Newer Units 1.6 gpm Over 3.0 for Non-efficient Valves Usually Use Heated Water Traditional “Showerhead” Type Spray Pattern Orifices Become Restricted with Time New “Knife-like” Continuous Spray – More Efficient, Less Mineral Buildup Ex. Water savings 77,050 gal/year Gas Savings 335 therms/year; 7600 kWh

12. What is It? Food Waste Pulping and Dewatering System to Replace Scraping Trough and Garbage Disposal System in Kitchens Uses Water to Move Material Scraped Off Plates to a Pulper Which Cuts Solid Waste into a Slurry Slurry Flows From Pulper to Water Extractor Unit Which Removes Water to Produce Odor-Free, Semi-dry pulp Extracted Water Returned to Feed Tray to Complete Closed-loop Cycle Water Level Automatically Controlled Small Amount 1-3 gpm Bled Off and Replaced System Eliminates Need to Separate Food Scraps, Paper and Plastic Waste Reduces Staff Time by Half Ex. POM 2 Systems, 2 Bldgs. – Cuts Daily Water Consumption from 9,240 to 1680 gallons Savings 2.76 Million gal/year SOMAT Disposal System

13. SOMAT SystemPulper and Hydra-Extractor

14. Boilerless Food Steamers • Atmospheric Compartment Food Steamers – Connected to an Incoming water Line and Utilize a Steam Boiler or Generator That Injects Steam at a Constant Rate During the Cooking Event • To Maintain Atmospheric Pressure, Rejected Steam Goes into Drain Requiring Additional Cooling Water • Boilerless Steamers Use a Water Reservoir in Bottom of Cooking Compartment in Lieu of a water Connection – Manual Fill and Drain. No Steam Leaves. • Better Energy Performance and Water Efficiency • Easier Cleaning • Now About 10 Different Manufacturers • Estimate of Savings – 500-1000 gallons per day plus Energy Savings, 3 gph vs. 20 to 40 gph

15. Boilerless Food Steamer

16. High Efficiency Washers • Most Are Front – Loaders • A Few Top Loaders Marginally Meet Standard CEE (Consortium for Energy Efficiency) • Toploaders ½ to 1/3 Price of Front Loaders • 36% Less Water • 60% Less Energy

17. Common Area Laundry Rooms Study • In-Unit Washer – 11,800 gal/year • Common Area Laundry Rooms 3600 gal/year per Apartment • 3.3 Times as Much Water Why? Residents with In-Unit Washers Tend to Operate Equipment More Often and Less Efficiently Advantages – Savings in Gas, Electricity and Sewage, Reduced Construction Expense, Increased Space in Units

18. Hospitals • Steam Sterilizers • Example – University of Washington • Why – Steam Sterilizers Use Cold Water to Temper Condensate from Steam (212 F) to Keep Water Entering Drain at or Below 140 F • Older Units – Constant Bleed of 1 gpm to Mix While Unit is Hot Including Idle Time • Install Water Saving Kit – Device or Components That Sense Effluent Temperature and Only Apply Water When Necessary to Reduce Effluent Temperature • Evaluation – Payback Less Than 3 months • Tests Resulted in 68 to 98% Reduction

19. Condensate Local Example – San Antonio Use Air Conditioning Condensate Free Resource – High Quality, Distilled Water If You Can Get to the Pipe, Catch It Typical Home 5-10 gal/day Larger Buildings Rule of Thumb 0.1 to 0.3 gallon per ton-hour Collect – Residential Bucket Under Drain Line Rout to Rain Barrel or Other Collection System Use Gravity flow

20. Condensate – Cont. • Other Buildings • Ex. 500 ton System @ 80 % Load (0.2 Factor) Produces 1.3 gpm or 56,000 Gal/Month • Case Study- San Antonio Library • Produce 1 gpm (43,200 gal/month) • Garden 26,000 square feet • Collection System – 3 Interconnected Concrete Cisterns (8400 gal capacity) • Collect from Sump Gravity Fed into Irrigation System • Total Cost $21,500, 1/3 that of Rainwater Harvest System • Another Example - River Center Mall – 12 MG of Condensate Used for Cooling Tower Makeup

21. Condensate – Cont. Another Bldg. Captures 6.2 million gallons per year Used for Boiler Feed Makeup water Cost $19,000 Installed Savings $26,000 / year Payback – 11 Months IOI – Possible Ordinance Mandating Collection System in New Large Buildings

22. Example Supermarket (CA) Focus on Cooling Average Concentration Ratio 2.45 Baseline Cycles of Concentration – Approach 6, Water Reduction Negligible Problems Scale Prevention in Condensers Wide Range of Scale Forming Minerals Calcium Carbonate, Calcium Sulfate, Calcium Phosphate, Magnesium Silicate Biological Fouling Corrosion Tested 3 Processes Only Effective Process was Alkalinity Control Operated at 5.5 Cycles of Concentration

23. Supermarket Cont. Benefits Reduced Water Use, Lower Water and Wastewater Charges Reduced Electrical Use Reduced Acid Washing, Life Extension of Cooling Tubes B/C Ratio 2 to 4 for Water and Wastewater Other Water Savings Use High Efficiency Spray Nozzles and Aerators on All Hand Sinks and Spray Tables Eliminate Garbage Grinders Replace Low Pressure Hoses with High Pressure Sprayers for Washing

24. Management Options Potential Savings (Percent) Turf maintenance 10 Turf maintenance, irrigation system 20 Maintenance, Irrigation Scheduling Mulching in Ornamental Gardens 20 Soil Amendments (Compost) 20 Irrigation Scheduling 25 Irrigation/Soil maintenance 65 to 75 Lawn to go Dormant 90 Hardware Options AutoRain Shut Off 10 Soil Moisture Sensors; Soil Probes 10 to 30 Improve Performance 40 Drip/Bubbler Irrigation 50 Gray Water Up to 100 Rain Barrel Catchment Up to 100 Landscape Design Options Landscape Design 19 to 55 Turf Reduction 19 to 35 Choice of Plants 30 to 80 From Gleick et al. Options for the Reduction of Outdoor Garden/Landscape Water Use

25. New Faucet Developments Hydropower Generator to Recharge Battery Uses PV Cell to Power Optical Sensor

26. Summary • Variety of Technologies and Techniques to Reduce Water Consumption • New Resource Soon Available • Army Water Conservation Website • Information on Policies, Technical Guidance, Case Studies, Best Practices Within Army and Other Sectors • Links to Information Sources • Further Information Contact Author at 217-398-5590 or email Richard.J.Scholze@usace.erdc.army.mil