1 © 2011 ARCADIS 14 September 2015 Fresh Water Supply Alternatives and Technologies Fresh Water Supply Alternatives and Technologies Community Advisory Committee Meeting September 28, 2011 Hinkley, California

2 © 2011 ARCADIS 14 September 2015 ARCADIS & Malcolm Pirnie Malcolm Pirnie’s Water Division is a subsidiary of ARCADIS, a global science and engineering consulting firm working in more than 100 countries Over 100 years experience designing, building and managing water treatment and water supply systems Broad experience at all scales of water supply applications, from rural systems to municipal and regional networks

3 © 2011 ARCADIS 14 September )Tie into Golden State Water Company 2)Central water treatment and distribution 3)Whole house water treatment 4)Add option of deeper wells 5)Trucking water Basic Fresh Water Supply Alternatives

4 © 2011 ARCADIS 14 September 2015 GSWC supplies potable water to Barstow Water is treated and meets current drinking water standards Build a 12-mile pipeline to carry water from Barstow to Hinkley Store and distribute water using a network of pipelines, tanks and pumps Option 1 Tie into Golden State Water Company (GSWC)

5 © 2011 ARCADIS 14 September 2015 Option 1 Tie into Golden State Water Company ADVANTAGES Source is public water system with known water quality Water is treated and monitored for drinking water standardsDISADVANTAGES Substantial time and cost required to construct transmission line and network of distribution pipelinesSubstantial time and cost required to construct transmission line and network of distribution pipelines Additional water quality monitoring may be requiredAdditional water quality monitoring may be required Long transit may cause water quality deteriorationLong transit may cause water quality deterioration Loss of independent water supplyLoss of independent water supply

6 © 2011 ARCADIS 14 September 2015 Option 2 Central Treatment and Distribution Would require drilling new supply wells Water will be treated and disinfected at a central treatment facility Treated water will be delivered to homes through a network of pipelines, tanks and pumps

7 © 2011 ARCADIS 14 September 2015 Option 2 Central Treatment and Distribution ADVANTAGES Water is treated and monitored for drinking water standards Treatment can be tailored to the water quality of the new wells New infrastructure for the area New infrastructure for the communityDISADVANTAGES Challenge to locate and develop reliable, long-term supply wellsChallenge to locate and develop reliable, long-term supply wells Substantial time and cost required to construct transmission line and network of distribution pipelinesSubstantial time and cost required to construct transmission line and network of distribution pipelines State law requires system to be managed as a formal water utilityState law requires system to be managed as a formal water utility

8 © 2011 ARCADIS 14 September 2015 Option 3 Whole House Water Treatment Treat and disinfect water entering the homes Treatment would include ion exchange media or reverse osmosis (RO) filters that are placed outside the homes and connect to the existing supply lines Equipment provider would conduct the necessary monitoring and maintenance

9 © 2011 ARCADIS 14 September 2015 Option 3 Whole House Water Treatment ADVANTAGES Relatively less implementation time and cost Equipment Federal/State certified Water equipment vendor maintains the equipment Local controlDISADVANTAGES Water quality varies well to wellWater quality varies well to well May require multiple treatment stages (pre-filter, core treatment, post-filter)May require multiple treatment stages (pre-filter, core treatment, post-filter) Some systems can generate waste streams that may need to be disposed to the septic tanksSome systems can generate waste streams that may need to be disposed to the septic tanks Must be installed on the propertyMust be installed on the property Requires performance testingRequires performance testing

10 © 2011 ARCADIS 14 September 2015 Next steps to pilot test equipment: Evaluate range of options for whole house water treatment Select candidate systems for pilot testing Pilot testing to begin in November 2011 Option 3 Whole House Water Treatment

11 © 2011 ARCADIS 14 September 2015 Option 4 Deeper wells ADVANTAGES Familiar approach Maintain existing plumbing May produce better quality? DISADVANTAGES DISADVANTAGES Construction impactsConstruction impacts Groundwater is in an “over draft” condition in many parts of the Mojave BasinGroundwater is in an “over draft” condition in many parts of the Mojave Basin Experts unsure about yield on west sideExperts unsure about yield on west side May not produce better quality?May not produce better quality?

12 © 2011 ARCADIS 14 September 2015 Option 5 Trucking of Water ADVANTAGES Easy to start-up Obtain high quality waterDISADVANTAGES Uses lots of gasUses lots of gas Traffic impactsTraffic impacts Regular deliveriesRegular deliveries Must insure quality is maintained during deliveryMust insure quality is maintained during delivery Tanks needed at houses or more frequent deliveriesTanks needed at houses or more frequent deliveries

13 © 2011 ARCADIS 14 September 2015 Gather stakeholder views Continue evaluation of options Coordinate with Regional Water Quality Control Board Coordinate with California Department of Public Health Conduct pilot testing of treatment devices Refine construction and time estimates Next Steps in Evaluation Process