Evaluating DPR and Desalination as Water Supply Options

CalAm’s Monterey Peninsula Project Poseidon – Carlsbad

Purpose: Reduced reliance on the Carmel River Purpose: Profit

Per Capita Water Use: 48.3 GPCD Per Capita Water Use: 160 GPCD

Discharge of Treated Wastewater: 29.6 MGD Discharge of Treated Wastewater: 140-180 MGD

Size: 6.4 MGD or 9.6 MGD Size: 50 MGD (Total 215 MGD) Largest ocean desalination facility in the Western Hemisphere

Environmental Protection: Subsurface intakes w/ treated wastewater to dilute brine discharges

Environmental Protection: Open ocean intake with greater marine life impacts than Encina Power Station. Will use flow augmentation to dilute brine (Flow augmentation is illegal for all other desalination facilities but Carlsbad).

Israel California

Household Water Use: 44 GPCD So. Cal. Household Water Use: 105 GPCD

Reuse of Wastewater: 94% Reuse of Wastewater: 13%

Water for Ag: 1.6 acre-feet per acre of land Water for Ag: 3 acre-feet per acre of land

Ocean Desalination DPR

Cost $1,900 to more than $3,000/AF The lowest cost of $685/AF for ATW

Energy Demand 9.50–14.75 kWh/gal 3.25–3.5 kWh/gal

Carbon Footprint 6.00 kg CO2e/gal 1.80 kg CO2e/gal

Water Supply Opportunity 0.4 Million ACY 1.1 Million ACY

Environmental Impacts Impingement & Entrainment;Indirect GHG EmissionsBrine ToxicitySea Level Rise

Indirect GHG EmissionsPossible Instream Flow Issues

Environmental & Social Benefits Provides a Local SupplyDrought Resilient

Provides a Local SupplyDrought ResilientReduces Wastewater Discharges

Direct Potable Reuse Regulations: • December 31, 2016 - Report to

the Legislature on the feasibility of developing uniform water recycling criteria for direct potable reuse.

• Future DPR Regulations.

Sean Bothwell, sbothwell@cacoastkeeper.org