Closing the Loop Approaches to Net Zero Water May 15, 2018 Presented to the Sixth Emerging Water Technology Symposium by Carmen Cejudo, PE, PAE
To be sustainable our culture must function as a mature ecosystem. - Toby Hemenway, Author of Gaia s Garden
Functional vs. Dysfunctional Systems Overview of Cycles
The Water Cycle
The Carbon Cycle
Our current systems are disconnected From the Humunaure Handbook
Closing the Loop includes the Nutrient Cycle From the Humunaure Handbook
Built Environment & The Broader Ecology
US Water Use Other Publically Supplied Uses 5.4% Industrial 5% Domestic 8.5% Aquaculture 2.6% Thermoelectic Power 41.5% Irrigation 37%
Energy & Water Nexus CEC 2005 Report California Water Related Energy Use Water Cleaning & Transportation 19% End use 81% End Use 81%
There is no one solution. Closing the loop is a process that depends on scale.
PAE s Six Steps to Net Zero Water
The first step strives to eliminate pollution
Top Causes of Pollution in Rivers and Streams Resource Urban Runoff/ Extraction 5% Stormwater 5% Construction Sites 0.15% Atmospheric Deposition 6% Agriculture 22% Unspecified Nonpoint 8% Sewage/Municipal Discharges 8% Hydromodification 14% Natural/Wildlife 9% Habitat Alteration 10% Unknown 11%
Pollutants at the Building Scale
Water Budget
Analyze the Ecosystem
Analyze the Ecosystem Rain income average yearly rainfall Inches 50 45 40 35 30 25 20 15 10 5 0 47 38 36 20 11 12 Seattle Tucson Portland San Francisco Los Angeles New York
Nature s Water Budget 9 Inches of Monthly Average Rainfall for Portland 8 7.9 7 6.93 6.86 Average Rainfall (in.) 6 5 4 3 4.22 4.67 3.26 3.09 3.56 2 1.77 1.48 1 0.52 0.79 0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Reduce Water Use How we use water Typical Household Water Use Office Building Water Use Drinking / Cooking 5% Bath / Shower 31% Toilet 44% Toilet 37% Washing & Others 28% Laundry 20% Cooling Towers 31% Garden / Landscaping 4%
Reduce Potable Water Use Solar Powered Waterless Water Efficient Dual-Flush Low Flow
Separate Water & Nutrient Streams Black Water Potable Water Grey Water Rain Water
Treat Using Natural Process
Architect: NBBJ Large Scale Urban Development Scale Jumping Impacts for Retail Water Usage OFFICE USAGE TO ROOF AREA NEEDED RETAIL TO ROOF AREA NEEDED Roof area needed: ~180,000 sf Roof area needed: ~1,000,000 sf
S Ne+ Architect: NBBJ
Small Scale Example: 4-Unit Retreat
Individual Scale
Individual Scale
STATS - Hospital - 155,000 sf - Two Floors Our desire is to open a wedge into the future so that we, and others can see what is possible in a contemporary office building. - Denis Hayes Bullitt Foundation, President BENCHMARKS - Pursuing LEED Gold - LEED fundamental and enhanced commissioning ENERGY - 20% Saved WATER - Efficient Fixtures - 20% Saved FEATURES - Built to operating room standards - LED lighting - Daylight harvesting - HVAC heat and recovery evaporative cooling
Medium Scale Example: Office Building
Medium Scale Example: Office Building
Greywater Treatment Lessons Learned Elevated tank required Must filter to a smaller size than the percolation holes. Concentration rises in the summer.
Living in a Living Building The Restroom Experience
Grrrrrrrrr
Composting Toilet System First Compost Removal
Composting Toilet System First Compost Removal No odors, just dry compost
Composting Toilet System Lessons Learned Larger Plumbing Chases Specify Equipment Designed for the Application Evenly distribute load Excess leachate is an issue for overloaded equipment Anticipate Post- Construction Changes
Rainwater to Potable
Recommendations
Blackwater Treatment Living Machine Constructed Wetland Composter Membrane Bioreactor
Wastewater Treatment Septic Tank
Effluent Management Drainfield
Wastewater Management Constructed wetlands
Wastewater Treatment Packaged treatment system Membrane Bioreactors Sequencing Batch Reactors
Greywater Treatment
Greywater Treatment Toilets and urinals flushed with reclaimed water DO NOT DRINK
Rainwater Treatment
Storing Embodied Solar Energy Challenges Properly sizing cistern Collection area
Rainwater Reclamation Portland State University, NW Center for Engineering (LEED Gold)
Potable Rainwater Lessons learned Anticipate long regulatory process Work with reviewer early in the project Required to become a water district
Verify Performance Metering: Total hot water use Total water use Tenant water use Cistern levels
Living Building Lessons
Creating a better environment Carmen Cejudo, PE, LEED AP Project Manager carmen.cejudo@pae-engineers.com 206.596.8606 1501 E Madison Street, Suite 300 Seattle, WA 98122