Desalination of Golf Irrigation Water

Typical 150 Acre Golf Course Uses About 200
Million Gallons per Year

Each Course Uses the Equivalent Water
Annually as 1,800 Residential Units at 300 gpd

50 Championship Golf Courses in Orange
County, CA Use About 10 BG or 30,000 AF/yr
200 MG/yr * 50 Courses
= 10,000,000,000 gal/yr
Equivalent to 10% of
Nevada’s water allotment
from the Colorado River

60% or 30 of 50 Orange County, CA Courses Use
Recycled or Non-Potable Groundwater
Why
1. It is mandated, especially during drought condition
2. It costs less, 50-90% of potable cost
3. It is the right thing to do environmentally

Three Benefits to Using Recycled Water for Golf
Course Irrigation:
1. It feels like the right thing to do (and accepted by
public as completely safe in OC)
2. More reliable supply
3. Reduces/eliminates fertilizers

Two Problems with Using Recycled Water for
Golf Course Irrigation:
Problem 1 of 2:
Impoundment storage can increase adjusted SAR and
dissolved manganese due to excess algae

Sodium Adsorption Ratio (SAR) is Indicator of Soil
Damage from Sodium
1. SAR is common ratio presented which compares equivalents of
sodium versus calcium/magnesium
2. Adjusted SAR takes into account availability of calcium – dependent
on pH and alkalinity
3. Lower pH makes calcium more available (free in solution) and frees
up nutrients in solution for the plant to obtain

Recycled Water Has High Nutrients, Causing High
Algae, pH Increases, Which Hurts SAR
1) 2 H 2 O + LIGHT -> 2H 2 + O 2
2) 2 H 2 + CO 2 -> [CH 2 O] + H 2 O
3) 2 HCO
-
3 -> CO 2 + CO
--
3 + H 2 O
4) CO
--
3 + H 2 O -> CO 2 + 2OH -
Alkalinity does not change but pH increases & CaCO3 precipitates

Mang (mg/L)
Periodic Low Oxygen Can Cause Manganese >0.2
mg/L, and Iron Deficiency Could Occur
Manganese Concentrations
0.6
0.5
Rattle Mn
UOR Top Mn
UOR Bottom Mn
0.4
0.3
0.2
0.1
0
12/3/2009 1/22/2010 3/13/2010 5/2/2010 6/21/2010 8/10/2010 9/29/2010 11/18/2010 1/7/2011 2/26/2011
Date

Two Problems with Using Recycled Water for
Golf Course Irrigation:
Problem 2 of 2:
High salt including sodium and chloride, and impurities
boron and ammonia can harm turf/soil

Higher Salt and Impurities Leads to the Following:
1. Higher leaching fraction needed to flush concentrated salts,
causing higher water cost and wet playing conditions
Turf Grass Species Salt Tolerance soil extract EC limit soil extract [TDS] limit
Poa Annua sensitive < 3 mS/cm < 2,000 mg/L
Bentgrass sensitive < 3 mS/cm < 2,000 mg/L
Perennial Ryegrass moderately tolerant 6 - 10 mS/cm 3,800 - 6,400 mg/L
Kikuyu moderately tolerant 6 - 10 mS/cm 3,800 - 6,400 mg/L
Bermuda tolerant > 10 mS/cm > 6,400 mg/L

Higher Salt and Impurities Leads to the Following:
1. Higher leaching fraction needed to flush concentrated salts,
causing higher water cost and wet playing conditions
Turf Grass Species Salt Tolerance soil extract EC limit soil extract [TDS] limit
Poa Annua sensitive < 3 mS/cm < 2,000 mg/L
Bentgrass sensitive < 3 mS/cm < 2,000 mg/L
Perennial Ryegrass moderately tolerant 6 - 10 mS/cm 3,800 - 6,400 mg/L
Kikuyu moderately tolerant 6 - 10 mS/cm 3,800 - 6,400 mg/L
Bermuda tolerant > 10 mS/cm > 6,400 mg/L
2. Higher quantities of soil amendments such as gypsum and
herbicides needed to maintain healthy turf
3. Increased aerification and sand top-dressing needed to
maintain soil permeability

Golfers Desire Firm and Fast Conditions, Which
is Impossible with Heavy Leaching

To Avoid Heavy Leaching and Soil Destruction from
High Sodium, Golf Courses Using RO Desalination

USA Golf Courses Using RO Desalination on
Recycled/Non-Potable Golf Irrigation Water
1. California’s Monterey Peninsula courses including Pebble
Beach, Spyglass, Spanish Bay
2. Florida Country Club Courses Seminole, Everglades, Osceola
3. Arizona’s Scottsdale Water Campus feeds partially desalinated
water to 23 golf courses

Study Looks at Three Golf Courses in Orange County,
CA for Economics of Irrigation Desalination
1. Course maintenance is challenged from high salts and impurities
Course Water Type Average [TDS] Average [Na+] Average [Cl-]
A Non-Potable
650 140 150
Groundwater
B Recycled Water 1,110 162 200
C Recycled Water 870 150 206
2. Brine disposal is available through direct or indirect ocean outfall
3. Land, power, and membership desire is present

Course C Existing Water Use: ET + Leaching Fraction to
Reduce Salt Concentration in Soils
0 1a 6 7 8 9 10 11 12 13
Adjusted
Leaching
Water
Total
Irrigation
Water
Course
Location Area
Irrigation Vol
Per Year
Leaching
Quantity
Leaching
Quantity
# of Leaches
per Year
Leaching
Water
%
Leaching
(ft^2) (gallons) (in/leach) (gallons) (gallons) (gallons) (gallons)
Greens 110,000 2,700,000 6 410,000 32 13,100,000 11,900,000 14,600,000 81.5
Fairways, 6,424,000 80,100,000 1.25 2,500,000 32 80,000,000 45,700,000 125,800,000 36.3
Tees,
Roughs,
Non-Green
60,100,000 1.25 2,500,000 32 80,000,000 54,200,000 114,300,000 47.4
Total 143,000,000 111,800,000 254,800,000 43.9

Course C: Analysis of Salt Concentration with 0.42
Leaching (Existing Conditions – No Desal)
[TDS] [TDS] [TDS] [TDS]
Applied Water Applied Water Bottom Root Zone Bottom Root Zone
(meq/L) (mg/L) (meq/L) (mg/L)
[Ca] 2.5 50 6.0 120
[Mg] 1.2 15 2.9 35
[Na] 6.5 149 15.5 356
[K] 2.6 102 6.2 242
[Cl] 5.9 209 14.1 499
[CO3] 0.66 20 0.3 8
[HCO3] 2.33 142 6.9 420
[SO4] 3.9 187 9.3 446
874 2,126
EC = 3,300

Existing Average Annual Operation and Maintenance
Cost of Courses A, B, and C

Course C: With Desal Leaching Fraction Decreases
from 0.42 to 0.14 (28% water reduction)
1. Same soil salt concentrations achieved with lower leaching
fraction, course firm/fast with higher value (not included in analysis)
2. RO will have about 15% waste reject, for net water savings of 13%
(28% - 15%). Irrigation pumping power savings will be 28%
• Soil enhancement gypsum reduced from 4,000 lb/day to 500 lb/day
4. $30K/yr savings in herbicides and $8K/yr savings in top-dressing
5. Labor savings not included at this time

Proposed Annual Operation and Maintenance Cost of
Courses A, B, and C with Desalination

Proposed Average Annual Operation and
Maintenance Cost of RO System

Proposed Average Annual Operation and
Maintenance Cost of RO System
ASSUMPTIONS
• Pre-treatment antiscalant (2 ppm) & acid (20 ppm)
• Post-treatment gypsum (100 ppm) and base (20 ppm)
• 13 week cartridge filter replacement
• 3 year UF and RO membrane replacement
• 225 psig total pumping not including irrigation pumps
• 1 man-hour per day at $35/hour
• $0.0015/gallon waste brine disposal fee
• $12,000/yr misc repair/replacement

Proposed On-Site Capital Cost including Installation
for Typical Recycled Water RO System
400 gpm RO Desalination System Capital Cost
RO Skid System $ 375,000
Pretreatment Skid System $ 320,000
Mechanical Equip & Install $ 199,250
Civil Works* $ 148,750
Electrical Equip & Install $ 218,000
Engineering $ 70,000
Contractor Overhead $ 189,150
Contingency $ 126,100
$ 1,650,000
* - does not include building or fencing
NOTE: 20 year capital repayment on $1.65M equals $135K/yr at 5%
discount, equal to about 10% extra O&M cost per year

RO Desalination May Be Used to Reduce High Boron
and Ammonia to Protect Cool Season Turf Grass

Conclusions
1. If brine disposal is feasible, operating costs for RO are offset
2. Repayment of capital cost increases the annual O&M 10%
3. This assumes no savings in labor, 20% reduced labor would
offset the capital
4. Extra foursome/day at $100/round

Systems Described Under Construction
Additional data will be collected
over the next two years for
future presentation, including
one full scale and one pilot
system operated on one green

For more information, or questions/
comments, please contact
Andy Komor, MS, PE
andy@pacewater.com
714-481-7225
www.pacewater.com