Analysis of Water Savings at the Presidio of Monterey

1
Analysis of Water Savingsat the Presidio of
Monterey

• March 15, 2004

2
Water Conservation Efforts at the POM

• 1998 to 2002 installed about 700 low-flow
  showerheads
• 1998 installed new irrigation system at
  Soldiers Field
• March 2000 issued Commandants water use policy
• May 2000 installed new irrigation system at Hill
  Top athletic field, installed artificial field at
  Price Fitness Center
• August 2000 installed water-efficient garbage
  disposal systems in two dining facilities
• December 2001 to March 2002 installed 173
  waterless urinals in offices, classrooms and
  recreational facilities
• 2002 removed irrigation systems around barracks
  that were prone to leaks and maintenance problems

3
Analytical Approaches to Quantify Conservation
Savings

• Comparison of monthly averages before and after
  conservation
• Regression analysis of monthly water use
  accounting for seasonality and weather
• Mechanical, or engineering estimates of savings
  from waterless urinals and SOMATs
• Water use profile based on water use coefficients
  and building square footage for two time periods
  (before and after conservation)

4
Summary of Estimated Savings
5
Monthly Average Water UsePre- and
Post-Conservation
6
Conclusions

• Water conservation efforts at the POM since March
  2000 have saved an estimated 1.65 acre-feet per
  month in indoor water use
• In summer months, water conservation efforts have
  saved an estimated 3.8 acre-feet per month
• Average monthly water use, both indoor and
  outdoor, has been reduced by 2.06 acre-feet per
  month

7
Conclusions Indoor Use

• Indoor water savings of 1.65 acre-feet per month
  (19.8 af/yr)
• SOMAT systems save 0.706 acre-feet per month
  (8.468 af/yr)
• Waterless urinals save 0.755 acre-feet per month
  (9.063 af/yr)
• Other indoor savings (e.g., showerheads) of 0.189
  acre-feet per month (2.268 af/yr)

8
SOMAT System Water Use

• Two troughs and two pulpers linked to one
  extractor per building
• X (2) 2.5 gallons per minute per pulper
• X 3.5 hours per day
• (840) 1050 gallons per day per building
• X 365 days per year
• (0.61) 0.77 million gallons per year
• (1.88) 2.35 acre-feet per year

9
SOMAT Water Savings

• (7,560) 7,140 gallons per day
• (2.759) 2.606 million gallons per year
• (8.468) 7.998 acre-feet per year

10
Revised Savings Estimate

• Waterless Urinals save 9.063 acre-feet per year
• SOMAT systems save 7.998 acre-feet per year