December 13, 2017 UPDATE

Transcription

1 December 13, 2017 UPDATE

2 Topics 1. Timeline 2. Scope of This Effort 3. Master Plan Findings 4. Next Steps

3 Timeline

4 Timeline of the Master Plan and Related Efforts Date 7/2008, 7/2009, 2/2010 Item Dates of prior Wastewater Master Plan (WWMP) and prior updates to the master plan (author: HDR) 2011 Ione indicates that it may invoke five-year cancellation clause 11/2011 HydroScience awarded WWMP update contract through competitive process 11/2012 Draft WWMP update submitted 6/2014 Multi-Regional Recycling Feasibility Study with Ione & CDCR initiated 8/2016 Multi-Regional Recycling Feasibility Study with Ione & CDCR completed 4/2017 This WWMP update initiated 7/2017 Ione invokes five-year cancellation clause 12/2017 Draft WWMP update submitted

5 Scope of This Effort

6 Scope of This Effort Update the 2012 WWMP with new information on flows, growth, and water balances and bring in the results of the Multi-Regional Study Compare Multi-Regional approach to standalone alternatives (elimination of storage and disposal downstream of Henderson) Address Henderson Reservoir change can now repair and keep in service Compare based on cost and non-cost factors Provide a recommendation and Capital Improvement Plan (CIP)

7 Scope Limitations No updating of TM 3B changes to surface water discharge requirements not significant to overall picture Reconsider risks and costs of surface water discharge option Rely on prior WWTP condition assessment information

8 Changes During Effort Ione invoked five-year cancellation clause and indicated no further interest in multi-regional solution Stand-alone alternatives are now the only feasible alternatives

9 Master Plan Findings

10 Report Outline TM 1: Evaluation of Existing Facilities TM 2: Flow Projections TM 3: Initial Evaluation and Screening Options TM 4: Alternatives Analysis TM 5: Capital Improvement Plan

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12 Current WWTP Influent Flows

13 Existing Conditions Water Balance Current

14 Existing Conditions Water Balance Without Ione Disposal

15 Other Findings WWTP needs condition and capacity improvements and/or facility replacements ARSA pipeline needs condition and capacity improvements Collection system Infiltration/Inflow (I/I) would be beneficial if cost-effective Sludge removal in Henderson would restore capacity

16 Projected Flows Gold Rush Ranch (GRR) 18 hole course irrigated with recycled water 1334 residential units Develop over 25 years beginning in 2020 (assumption) Uncertainty surrounding this development going forward or in what form Modest Population Growth in Service Area

17 Population Growth

18 25-Year Flow Projections

19 Flow Projection Findings Flows will exceed the current ADWF capacity of the WWTP before 2036 without GRR and 2031 with GRR PDF will exceed wet weather capacity in 2021 ARSA flow bottleneck of 2.0 MGD will be exceeded in 2026 ARSA storage and disposal capacity will be exceeded

20 Surface Water Discharge Evaluation (TM 3B) TM 3B prepared in 2012 by RBI, still applies today Requires nutrient removal, Title 22 filtration, ultraviolet disinfection Higher O&M cost: Grade III operator, maintenance, energy, reporting, fines potential Dilution credit and seasonal discharge benefits limited Eliminates ARSA system and associated costs Ends reclamation practice unless portion diverted to new recycled water users, difficult to divert from creek later High cost for permitting+studies, environmental, design Schedule uncertainty to complete these, urgency to complete given cancellation clause Final effluent limitations uncertain until studies done Anti-degradation analysis is required; must evaluate alternatives to surface water discharge

21 Alternatives Evaluated

22 Alternatives Evaluated

23 Alternative 1: ARSA Sprayfields

24 Alternative 2: Noble Ranch Sprayfields

25 Alternative 3: Surface Water Discharge

26 Alternative 4: ARSA Sprayfields and GRR Irrigation

27 Alternative 5: Surface Water Discharge and GRR Irrigation

28 Alternatives Analysis

29 Alternatives Analysis

30 Evaluation Findings Alt. 1 is more costly on a present worth basis than Alt 3 But, spending can be phased further out in time than Alt 3, which must replace entire ARSA system when Ione goes offline (or interim measures taken) Alt 1 scores better than Alt 3 in non-economic analysis Alt 1 uses a familiar and accepted disposal strategy and can be adapted to future reuse of effluent The actual cost and timing of Alt 3 is less certain

31 Recommended Alternative: Alternative 1: ARSA Sprayfields Lower system not needed if sufficient acreage developed at Henderson Potential sprayfield sites shown. Not all will be required. CIP based on single site at similar elevation to Henderson.

32 Treatment Upgrades

33 Capital Improvement Program

34 Capital Improvement Program

35 Capital Improvement Program Henderson sludge removal and initial sprayfields mitigates loss of Ione disposal Engineering and permitting for Ione Canal begins in first 5 years period, construction in next WWTP costs potentially could be further spread out

36 Next Steps

37 Next Steps Updated WWTP assessment and preliminary design of upgrades Ione Canal Reservoir geotechnical study, preliminary design, CEQA, land acquisition Landowner coordination and agreements, sprayfield development Phasing refinement and value engineering Seek low-interest loans and grants

38 Option: Recycled Water Feasibility Study Determine if sufficient market exists to sell higher quality recycled water to local users and feasibility/cost of providing it Utilize flow projections, water balances, tertiary treatment costs, and storage and disposal amounts from WWMP as basis Develop and evaluate tertiary reuse alternatives Compare to land disposal alternatives in the WWMP

39 Option: Recycled Water Feasibility Study State Water Resources Control Board (SWRCB) Water Recycling Funding Program (WRFP) Grant: up to $75,000 50/50 match Recycled Water Market Assessment Legal/Institutional Analysis Recycled Water Supply Analysis

40 Input and Direction Comments and questions on the analysis and recommended alternative Finalize the WWMP Interest in recycled water market assessment/study

41 End of Presentation