240 Country Club Road, Suite A
Eugene, Oregon 97401
541-338-8135
FAX: 541-338-8180
Crescent City
Recycled Water Feasibility
Study (RWFS)
5 January 2023
Prepared for
City of Crescent City
377 J Street
Crescent City, California 95531
KJ Project No. 2076056*00
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List of Tables.................................................................................................................................v List of Figures.............................................................................................................................. vii List of Appendices....................................................................................................................... vii ES. Executive Summary.....................................................................................I ES.1 Overview and Summary of Findings .......................................................I ES.2 Background .............................................................................................I ES.3 City Water Supply and Wastewater Facilities..........................................I ES.4 Recycled Water Market Assessment .....................................................II ES.5 Project Alternatives Development and Analysis....................................III ES.6 Recommended Plan and Next Steps ................................................... IV ES.7 Financial Considerations...................................................................... IV Section 1 Introduction .................................................................................. 1
1.1 Background ............................................................................................1
1.2 Grant Funding Requirements.................................................................3
1.3 Study Objectives ....................................................................................3
1.4 Study Partners .......................................................................................4
1.5 Relevant Studies ....................................................................................4
1.6 Study Organization.................................................................................5 Section 2 Study Area Characteristics........................................................13
2.1 Project Setting......................................................................................13
2.1.1 Del Norte County.......................................................................13
2.1.2 City of Crescent City .................................................................13
2.1.3 Study Area Boundaries .............................................................15
2.2 Surface Hydrology................................................................................15
2.3 Groundwater Basin ..............................................................................17
2.4 Water Quality .......................................................................................17
2.4.1 Groundwater Quality .................................................................17
2.4.2 Surface Water Quality...............................................................18
2.5 Land Use..............................................................................................20
2.6 Population Projections..........................................................................20
2.7 Beneficial Uses of Receiving Waters ...................................................20 Section 3 Water Supply Characteristics and Facilities .............................23
3.1 Wholesale and Retail Entities...............................................................23
3.2 Source of Water ...................................................................................23
3.2.1 Groundwater Management .......................................................26
3.3 Current Water Supply Facilities............................................................26
3.3.1 Ranney Well Collector...............................................................27 Table of Contents (cont'd)
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3.3.2 Distribution System and Storage Reservoirs ............................27
3.4 Water Fees...........................................................................................28
3.5 Historical and Projected Water Use Trends .........................................28
3.6 Quality of Water Supplies.....................................................................29
3.7 Potential Future Water Sources ...........................................................29
3.7.1 Water Conservation Efforts.......................................................29 Section 4 Wastewater Characteristics and Facilities ...............................31
4.1 Wastewater Facilities ...........................................................................31
4.1.1 Wastewater Collection System .................................................31
4.1.1.1 Wet and Dry Weather Flows...................................31
4.1.2 Wastewater Treatment Facility..................................................32
4.1.2.1 Primary Treatment ..................................................32
4.1.2.2 Secondary Treatment .............................................32
4.1.2.3 Tertiary Treatment ..................................................33
4.1.2.4 Existing UV Disinfection System for Recycled
Water ......................................................................33
4.1.2.5 Solids Handling.......................................................34
4.1.2.6 Discharge................................................................34
4.2 Wastewater Facility Operations and Maintenance...............................38
4.3 Water Quality of Effluent ......................................................................38
4.4 Existing Wastewater Flows ..................................................................39
4.4.1 Seasonal Flow Variation ...........................................................39
4.4.2 WWTF Influent Flow Split..........................................................39
4.4.2.1 Current Flow Split ...................................................40
4.4.2.2 Future Flow Split Post Membrane
Replacement...........................................................40
4.5 Commercial and Industrial Treatment Facilities ...................................40
4.5.1 Rumiano Cheese Company ......................................................40
4.5.1.1 Rumiano MBBR/DAF Pre-Treatment System.........41
4.5.1.2 Rumiano UV/RO Pre-Treatment System................44
4.5.1.3 Rumiano’s Effluent Water Quality...........................44
4.5.2 Seaquake Brewery....................................................................45
4.5.3 Port O’Pints Brewery.................................................................45 Section 5 Treatment Requirements ........................................................... 47
5.1 Multi-Barrier Approach .........................................................................47
5.2 Overview of Regulatory Requirements.................................................49
5.2.1 State Recycled Water Policy.....................................................50
5.2.2 Statewide General Order ..........................................................51
5.3 Non-Potable Reuse Requirements.......................................................51
5.3.1 Non-Potable Treatment Processes ...........................................52
5.3.2 Customer Based Water Quality Objectives...............................53
5.3.2.1 Irrigation Requirements ..........................................53 Table of Contents (cont'd)
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5.3.2.2 Commercial/Industrial .............................................54
5.4 Potable Reuse Treatment Requirements.............................................55
5.4.1 Potable Treatment Processes...................................................55
5.4.2 Groundwater Recharge Reuse Treatment Requirements.........58
5.4.3 Surface Water Augmentation Treatment Requirements ...........60
5.4.4 Direct Potable Reuse Treatment Requirements .......................62
5.4.5 Brine Disposal Requirements....................................................64
5.5 Streamflow Augmentation Treatment Requirement .............................64
5.6 Summary of Treatment Process and Credits .......................................64
5.7 Summary of Non-Potable and Potable Reuse .....................................67 Section 6 Recycled Water Market .............................................................. 69
6.1 Market Assessment Approach .............................................................69
6.2 Non-Potable Reuse (NPR) Market Assessment ..................................69
6.2.1 Identifying Potential Recycled Water Users ..............................70
6.2.2 Non-Potable Recycled Water Demand .....................................72
6.2.2.1 Irrigation Demands .................................................72
6.2.2.2 Potential Industrial Users........................................77
6.2.2.3 Potential Other Users .............................................78
6.3 Potable Reuse Market Assessment .....................................................78
6.3.1 Indirect Potable Reuse (IPR) ....................................................78
6.3.2 Direct Potable Reuse (DPR) .....................................................79 Section 7 Screening and Design Criteria Assumptions .............................80
7.1 Preliminary Screening Criteria and Results..........................................80
7.1.1 Customer’s Interest...................................................................80
7.1.2 Total Demand............................................................................80
7.1.3 Proximity to Recycled Water Source.........................................81
7.1.4 Availability of Recycled Water...................................................81
7.1.5 Environmental Considerations ..................................................84
7.1.6 Preliminary Customer Screening Results .................................84
7.2 Preliminary Design Criteria...................................................................84
7.2.1 Irrigation Demands....................................................................84
7.2.2 Available Recycled Water Production Assumptions .................85
7.2.3 Facility Sizing Criteria and Assumptions ...................................86
7.2.3.1 Treatment Facilities.................................................86
7.2.3.2 Storage Facilities ....................................................86
7.2.3.3 Pipelines .................................................................87
7.2.3.4 Pumps.....................................................................87
7.2.3.5 Site Irrigation Facilities............................................88
7.3 Cost Estimate Approach.......................................................................88
7.3.1 Capital Costs Approach and Assumptions................................89
7.3.2 Operation & Maintenance Cost Approach and
Assumptions.............................................................................90 Table of Contents (cont'd)
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7.3.3 Potable Water Costs Approach and Assumptions ....................91 Section 8 Project Alternatives Description................................................92
8.1 Alternative 1 – Irrigation of Beach Front Park ......................................92
8.1.1 Description of Proposed Facilities.............................................92
8.1.1.1 Treatment Facilities.................................................92
8.1.1.2 Storage and Conveyance Facilities ........................93
8.1.2 Cost Estimate............................................................................95
8.2 Alternative 2 – Irrigation of Beach Front Park + Truck Fill Station .......95
8.2.1 Description of Proposed Facilities.............................................95
8.2.2 Cost Estimate............................................................................98
8.3 Alternative 3 – Irrigation of Peterson Park............................................98
8.3.1 Description of Proposed Facilities.............................................98
8.3.1.1 Treatment Facilities.................................................99
8.3.1.2 Storage and Conveyance Facilities ........................99
8.3.2 Cost Estimate..........................................................................102
8.4 No Project Alternative.........................................................................102 Section 9 Project Alternatives Analysis...................................................106
9.1 Alternatives Screening Approach.......................................................106
9.1.1 Screening Criteria ...................................................................106
9.1.2 Raw Scoring............................................................................107
9.1.2.1 Engineering and Operational Considerations .......110
9.1.2.2 Economic Considerations .....................................110
9.1.3 Weighting Approach................................................................111
9.2 Project Alternatives Scoring and Ranking Results.............................112 Section 10 Recommended Project, Implementation & Operation Plan ....113
10.1 Recommended Project.......................................................................113
10.2 Implementation Plan...........................................................................113
10.2.1 Coordination............................................................................113
10.2.1.1 Project Alternative 1 - Beach Front Park...............113
10.2.1.2 Project Alternative 3 - Irrigation for Peterson Park ......................................................................113
10.2.2 Ability and Timing of Users to Join System.............................114
10.2.3 Tentative Water Recycling Requirements...............................114
10.2.3.1 Project Alternative 1 – Irrigation of Beach
Front Park .............................................................114
10.2.3.2 Project Alternative 3 – Irrigation of Peterson Park ......................................................................115
10.2.4 Commitments from Potential Users ........................................116
10.2.5 Water Rights Impact................................................................116
10.2.6 Permits, Right-of-Way, Design, and Construction...................116 Table of Contents (cont'd)
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10.2.7 Detailed Schedule...................................................................116
10.2.7.1 Beach Front Park Project Schedule......................116
10.2.7.2 Peterson Park Project Schedule...........................117
10.3 Operational Plan ................................................................................120
10.3.1 Responsible Parties ................................................................120
10.3.2 Equipment Operations and Maintenance................................121
10.3.3 Monitoring ...............................................................................121
10.3.3.1 Project Alternative 1 – Irrigation of Beach
Front Park .............................................................121
10.3.3.2 Project Alternative 3 – Irrigation of Peterson Park ......................................................................121
10.3.4 Recycled Water Delivery Scheduling......................................121 Section 11 Construction Financing and Revenue Plan..............................122
11.1 Construction Funding Sources and Considerations ...........................122
11.1.1 Grants and Loans....................................................................122
11.1.2 Short Term or Long-Term Bonds ............................................124
11.1.3 Utility Rates.............................................................................125
11.2 Recycled Water Pricing Policy Options ..............................................125
11.3 Costs That Can Be Allocated to Water Pollution Control ...................125
11.4 Annual Projections .............................................................................125
11.4.1 Water Prices for Each User or Category of Users ..................125
11.4.2 Recycled Water Used by Each User.......................................125
11.4.3 Annual Costs of Recycling Project..........................................126
11.4.4 Allocation of Costs to Users....................................................126
11.4.5 Unit Costs to Serve Each User or Category of Users and Unit Pricing .............................................................................126
11.4.6 Sensitivity Analysis Assuming Portion of Potential Users .......126
11.5 Sunk Costs and Indebtedness ...........................................................126 References................................................................................................................................127 List of Tables
Table ES – 1. Recycled Water Project Alternatives Evaluated Table ES – 2. Project Alternative Scoring Results
Table 1-1. Relevant Planning Documents
Table 1-2. Report Content Summary Per WRFP Recommended Outline Table 2-1. Crescent City 2021 Drinking Water Sampling Results Table 2-2. Projected Population Growth Rate for 2021 to 2045 Table 2-3. Beneficial Uses of the Receiving Waters for the City WWTF Effluent Table 3-1. Maximum Permitted Pumping Rates
Table of Contents (cont'd)
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Table 4-4. Rumiano Cheese Company 2021 Monthly Effluent Flows and Water Quality Data Table 5-1. Recycled Water Quality Guidelines for Irrigation Table 5-2. Summary of GRR Regulations for Direct Injection Table 5-3. Potential Pathogen LRV Credits for GRR with Full Advanced Treatment Table 5-4. SWA Criteria and Treatment Requirements
Table 5-5. Potential Pathogen LRV Credits for SWA with Full Advanced Treatment Table 5-6. Potential Pathogen LRV Credits for DPR with Full Advanced Treatment Table 5-7. Summary of Treatment Technologies
Table 5-8. Summary of Potential LRV Credits for Unit Treatment Processes Table 5-9. Summary of Pros and Cons for Each Reuse Type Table 6-1. Community Engagement Response Summary
Table 6-2. Monthly Evapotranspiration and Precipitation Table 6-3. Calculated Irrigation Demand Summary
Table 7-1. Irrigation Demands for Recycled Water Production and Infrastructure Sizing Table 7-2. Recycled Water Production
Table 7-3. Storage Facilities Design Criteria
Table 7-4. Pipeline Design Criteria
Table 7-5. Pump Design Criteria
Table 7-6. AACE Cost Estimate Classification
Table 7-7. Summary of Capital Costs Approach and Assumptions Table 7-8. O&M Cost Assumptions
Table 8-1. Alternative 1 – Facility Summary
Table 8-2. Alternative 1 – Summary of Probable Costs
Table 8-3. Alternative 2 – Summary of Probable Costs
Table 8-4. Alternative 3 – Facility Summary
Table 8-5. Alternative 3 – Summary of Probable Costs
Table 8-6. Comparison of Recycled Water Unit Cost to Potable Water Unit Cost for Each Alternative
Table 9-1. Summary of Screening Criteria and Considerations Table 9-2. Guidance for Scoring Screening Criteria
Table 9-3. Criteria Weighting for Sensitivity Scoring Scenarios Table 9-4. Scoring Results
Table 10-1. Summary of Operational Plan Considerations
Table 11-1. Summary of Potential Grant/Loan Options
Table of Contents (cont'd)
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Figure 1-1. Region Overview & City Location Map .......................................................................2 Figure 2-1. Crescent City Location and Topography ..................................................................14 Figure 2-2. Recycled Water Study Area Boundary .....................................................................16 Figure 2-3. Groundwater Basin Boundary and Geologic Features .............................................19 Figure 2-4. General Plan Land Use Diagram..............................................................................22 Figure 3-1. Existing Water System Map......................................................................................24 Figure 3-2. Existing Water System Hydraulic Profile ..................................................................25 Figure 4-1. Cresent City Wastewater System.............................................................................35 Figure 4-2. WWTF Process Flow Diagram .................................................................................36 Figure 4-3. WWTF Recirculation Pipe Photos ............................................................................37 Figure 4-4. Rumiano Cheese Company Pretreatment System...................................................42 Figure 4-5. Rumiano Cheese Company Site Plan ......................................................................43 Figure 5-1. Multi-Barrier Approach to Reuse ..............................................................................48 Figure 5-2. Types of Non-Potable Reuse and Associated Treatment Processes.......................53 Figure 5-3. Types of Potable Reuse ...........................................................................................57 Figure 6-1. Non-Potable Recycled Water Demand Market Assessment Map ............................73 Figure 6-2. Non-Potable Recycled Water Demand Market Assessment Map, Close-Up ...........74 Figure 7-1. Recycled Water Supply and Demand Analysis for Beach Front Park and Point of Honor.........................................................................................................................82 Figure 7-2. Rumiano Average Effluent and Nearby Irrigation Demands.....................................83 Figure 8-1. Alternative 1: Irrigation of Beach Front Park.............................................................94 Figure 8-2. Alternative 2: Irrigation of Beach Front Park and Truck Fill Station ..........................97 Figure 8-3. Alternative 3: Irrigation of Peterson Park ................................................................101 Figure 8-4. Beach Front Park Total RW vs. PW Cost – Current and Projected Trends............104 Figure 8-5. Beach Front Park Irrigation RW (O&M Only) vs. PW Cost – Current and Projected Trends .....................................................................................................................105 Figure 10-1. Beach Front Park Project Schedule......................................................................118 Figure 10-2. Peterson Park Project Schedule...........................................................................119 List of Appendices
Appendix A: SWRCB Funding Agreement
Appendix B: Recycled Water Uses Allowed in California
Appendix C: Data Used for Analysis
Appendix D: Engineers Opinion of Probable Costs
Appendix E: Detailed Scoring and Ranking Evaluation
Appendix F: Permitting Pathway Materials
Appendix G: Meeting Materials
Appendix H: Abbreviations
Crescent City Recycled Water Feasibility Study (RWFS) Executive Summary - I \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx ES. Executive Summary
ES.1 Overview and Summary of Findings
The City of Crescent City (City) received a grant of $150,000 and hired Stover Engineering and Kennedy/Jenks Consultants, Inc. (Kennedy Jenks) to evaluate the feasibility of implementing recycled water projects at the City. The most feasible alternatives were the irrigation of existing urban parks using recycled water either produced at the City's WWTF or treated and disinfected industrial effluent from Rumiano Cheese Company. While the projects are technically feasible, the cost to produce recycled water and maintain a recycled system for irrigation of parks is approximately 1.5 times that of continuing to use potable water currently. If the City were able to obtain grants for the construction of the recycling facilities and distribution systems, then it may be economically feasible to implement recycled water projects. If the cost to produce potable water increases substantially over time, then the City should reevaluate recycled water as an alternative supply. Current projections based on expected potable water rate increases, recommend a review in 15 years or approximately by 2037. There may also be changes related to regulatory requirements, or community preference that would justify an earlier review of the feasibility of implementing a recycled water project for the City.
ES.2 Background
The City is located on the Northern California coastline in Del Norte County with a population of approximately 6,673 people. Crescent City and the surrounding region receive 70 to 80 inches of rain annually, with the majority of the rainfall occurring in the fall and winter months. Due to the region’s climate, Crescent City’s water supply has not been significantly affected by drought conditions seen in other regions of California, and all water demands have been met using potable water. Although all of the City’s water needs are met through potable water, the City is interested in pursuing recycled water projects if it proves to be beneficial for the community.
This Recycled Water Feasibility Study (RWFS) was developed to identify viable recycled water alternatives, increase the understanding of recycled water opportunities for the region, and complete a feasibility study to evaluate, compare and document the potential alternatives for recycled water and the requirements for implementation of those projects. This study is a joint project between the City, who is responsible for potable water supply in the City’s service area, and the State of California, who is funding the project through the State Water Resources Control Board’s (SWRCB) Water Recycling Funding Program. This document is intended to help guide the City to identify potential recycled water projects that would be viable for the future.
ES.3 City Water Supply and Wastewater Facilities
The City water supply system relies entirely on the groundwater underflow of the Smith River, and its major water facilities include: 1) The Ranney Well Collector, 2) 14-inch transmission main and chlorination facility, 3) Elevated storage reservoir, and 5) distribution mains and storage reservoirs through the City’s water service area. The City does not have a water Crescent City Recycled Water Feasibility Study (RWFS) Executive Summary - II \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx treatment plant and does not have plans to construct one in the future, unless requirements change for the source treatment needs.
The City and the County Service Area (CSA), an agency of Del Norte County, each own separate wastewater collection systems. The CSA’s wastewater collection system collects wastewater from the unincorporated areas outside the City limits and includes 16 pump stations.
The flows generated and collected within the CSA system are conveyed to the City’s collection system which combines City and CSA generated flows to the City’s Wastewater Treatment Facility (WWTF) located on Battery Street.
The City owns and operates the WWTF, which treats wastewater to secondary standards for discharge though an outfall to the Pacific Ocean under the NPDES Waste Discharge Permit Order No. R1-2017-0002. The WWTF consists of primary treatment via screening and clarifiers, and then the flow is split and undergoes secondary treatment through a rotating biological contactor (RBC) and tertiary treatment through a membrane bioreactor (MBR). The effluent from the RBCs and the MBR is then combined before being discharged to the ocean outfall. The split of the influent flow between the RBC and MBR is required to meet the NPDES effluent discharge permit requirements. A UV disinfection system was installed at the WWTF in 2010 for providing recycled water to a future golf course for irrigation. However, the future golf course was not developed, and the UV disinfection system was never operated. The UV system currently remains offline at the treatment plant.
The City has various industrial users that produce industrial effluent and discharge to City sewer under pre-treatment permits. The three mayor industrial users within the City that produce industrial effluent are Seaquake Brewery, Port O’Pints Brewery, and Rumiano Cheese Company. Of these three industrial facilities, Rumiano Cheese Company produces the most effluent that could potentially be reused.
ES.4 Recycled Water Market Assessment
A recycled water market assessment was performed in two parts to identify the potential market for recycled water use within the study area boundary: 1) the non-potable market approach and 2) the potable market approach. The non-potable market approach consisted of identifying nonpotable water demands based on assessing annual meter data provided by the City and estimated irrigation demands. The potable market approach consisted of assessing potable demand requirements based on the capacity of suitable environmental buffers and future potable water demands.
Potential non-potable demands identified included irrigation demands for parks, commercial and industrial non-potable demands (toilet flushing, cleaning water, and landscape irrigation), and other demands such as dust control and agricultural use. Potential recycled water users within the City were identified and included City parks, truck fill station to supply agriculture or construction users, industrial users (such as breweries), Del Norte County Regional Airport, and Pelican Bay State Prison. After conversations with City staff and community engagement, potential recycled water users were narrowed down using a screening approach that consisted of four screening criterions: 1) Customer’s interest, 2) Total Recycled Water Demand, 3) Proximity to Recycled Water Source, 4) Availability of Recycled Water and, 5) Environmental Considerations. The screening approach indicated the best candidates for a recycled water Crescent City Recycled Water Feasibility Study (RWFS) Executive Summary - III \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx project was Beach Front Park and Peterson Park with recycled water produced at the WWTF and Rumiano, respectively.
The potable reuse options considered for this study included indirect potable reuse (IPR), such as Groundwater Replenishment and Surface Water Source Augmentation, and direct potable reuse. Potable reuse options were assessed using a qualitative approach. It was concluded that there are no foreseeable needs to augment the City’s potable water supply and current water facilities were not suitable for implementation of either direct or indirect potable reuse.
ES.5 Project Alternatives Development and Analysis
Three project alternatives evaluated are summarized in Table ES – 1 below.
Table ES – 1. Recycled Water Project Alternatives Evaluated Alternative Description
Source
Water
Facilities
Required
Average
Day
Demand
(GPD)
Demand
Description
Annualized
RW Cost
($/AF)
1 – Irrigation
of Beach
Front Park
RW produced
at WWTF and
used for
irrigation of
Beach Front
Park
Tertiary
disinfected
effluent
from WWTF
Plant
treatment
upgrades,
storage tank,
pipelines,
pumps, park
irrigation
system
56,000 Estimated
irrigation
demand of
Beach Front
Park
$2,000
2 – Irrigation
of Beach
Front Park
and Fill
Station
RW produced
at WWTF and
used for
irrigation of
Beach Front
Park and a
truck fill station
Tertiary
disinfected
effluent
from WWTF
Plant
treatment
upgrades,
storage tank,
pipelines,
pumps, park
irrigation
system, fill
station
components
60,000 Estimated
irrigation
demand of
Beach Front
Park and Fill
Station
(assuming
4,000
gallons/truck
fill)
$1,940
3 – Irrigation
of Peterson
Park
Irrigation of
Peterson Park
using Rumiano
Industrial
Effluent
Rumiano
treated and
disinfected
industrial
effluent
Storage tank,
pipelines,
pumps, park
irrigation
system
10,000 Estimated
irrigation
demand of
Peterson
Park
$2,600
Each project alternative was scored and ranked based on a qualitative and quantitative screening approach. A score of 1 to 3 was assigned based on recycled water availability, infrastructure requirements, administrative complexity, cost effectiveness, capital and O&M costs, funding and financing opportunities, and input from City staff. Scores were summed to Crescent City Recycled Water Feasibility Study (RWFS) Executive Summary - IV \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx give each project alternative a total raw score. A weighted score was also applied to each of the raw scores based on the relative importance of each screening criteria. Project alternative scoring are summarized in Table ES – 2.
Table ES – 2. Project Alternative Scoring Results
Weighed Scores
Alternative
Total Raw
Score
Baseline
(Balanced)
Minimize
Administrative
Complexity
Maximize
Engineering &
Operational
Considerations Low Cost
1 – Beach Front
Park 18.0 78 77 69 81
2 – Beach Front
Park & Fill
Station
17.7 76 76 66 82
3 – Peterson
Park 16.9 74 72 71 70
In addition to the three project alternatives above, the City could also pursue a no project alternative and continue to use potable water to meet their demands. It was determined that potable costs for meeting irrigation demands were lower than using recycled water which would require capital and operations and maintenance cost for the recycled water facilities. However, recycled water may become more cost effective in the future, depending on the increase of potable water rates. An economic comparison between using potable water and implementing Project Alternative 1 was completed, and it was determined that if potable water rates increased annually at 3%, recycled water would be more cost-effective beginning in 2053. If potable water rates increased annually at 6%, recycled water would be more cost-effective beginning in 2036.
However, if the City were able to receive full funding for the capital cost, recycled water would be more cost-effective sooner. The City should reassess the cost effectiveness of recycled water in 15 years, or sooner if rates for potable water increase significantly.
ES.6 Recommended Plan and Next Steps
A recommended project was not suggested for this study based on feedback and discussions with the City. The City preferred Alternatives 1 and 3 as viable options for a recycled water project. Steps for implementation include 1) coordination, 2) ability and timing for users to join system, 3) tentative water recycling requirements such as permitting, 4) verifying commitments from users and, 5) implementing a project schedule for design and construction.
ES.7 Financial Considerations
The successful implementation of these recycled water projects and services would require cooperative efforts within the City and Rumiano, if that project alternative was selected. Since Crescent City does not have a recycled water rate structure, a comprehensive cost of service Crescent City Recycled Water Feasibility Study (RWFS) Executive Summary - V \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx study would be recommended to determine the appropriate cost allocations and recycled water rates.
A large portion of recycled water projects costs are initial costs incurred to construct the system.
Funding these significant construction costs is one of the largest obstacles to overcome when implementing a recycled water system. Funding mechanisms that may be considered by the City include but are not limited to: short and long-term bonds, grants and loans, utility rates, and capacity fees.
Pricing recycled water is a complex policy decision that considers not only the cost of producing the water but also factors such as the type of recycled water project being implemented, who benefits from the water/project, the level and extent of cost sharing and equity, the age of the recycling system, the potential demand for recycled water, public perceptions, and the impacts to the other utilities.
For potential implementation of project Alternatives 1 and/or 3, the City would need to further evaluate what is economically feasible and what funding mechanism to pursue.
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This section provides a description of the City of Crescent City, study objectives for this Recycled Water Feasibility Study (RWFS), relevant studies completed previously, study organization, and study partners.
1.1 Background
The City of Crescent City (City) is located along the Northern California coast in Del Norte County approximately 15 miles south of the Oregon Border, as shown on Figure 1-1. The City is a common stopping point for tourists traveling Highway 101 and hosts the Smith River National Recreational Area, a well-known commercial and recreational fishing area. Besides tourism, major industries in the region include agriculture, timber, fishing, and the Pelican Bay State Prison.
Crescent City owns and operates a wastewater treatment plant, sewer collection facilities, storm drain infrastructure, and water distribution facilities that serve the community, city services, and public recreation. The County Service Area (CSA) also maintains a separate sanitary sewer collection system that serves the unincorporated areas outside the City limits. Flows generated within the CSA are conveyed to the City’s collection system, which ultimately flows to the Wastewater Treatment Facility (WWTF). The City supplies potable water to approximately 17,840 customers, including three community service water districts and the Pelican Bay State Prison (Urban Water Management Plan, 2020). The City’s water supply comes entirely from the groundwater underflow of the Smith River, with no connection to an imported water source. At Crescent City, the Smith River has a watershed area of about 700 square miles and an average annual rainfall of 70-80 inches/year.
There are three main industrial water and wastewater customers within the Crescent City limits.
These facilities are not City owned but discharge their industrial process water to the City’s sewer system under a pretreatment discharge permit. These facilities include Rumiano Cheese Company, Seaquake Brewery, and Port O’Pints Brewery
The mission of the City is to promote high quality leadership, services, and life to residents, businesses, and visitors by providing effective, innovative, and economically sound municipal services. This report examines whether recycled water use presents an opportunity for the City to meet this mission, through the beneficial reuse of treated and disinfected effluent from the treatment plant, reducing discharge of effluent to the ocean. In addition, the City recognizes that recycled water may be an untapped resource that may be utilized for irrigation of the City’s parks, strengthening partnerships with local industrial facilities. ³ City of Crescent City
Crescent City, CA
Region Overview &
City Location Map
K/J 2076056*00
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Figure 1-1
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Scale: Feet
Legend
City of Crescent City Limits
Del Norte County Boundary
State Boundaries
Source: Esri, Maxar, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community California
Oregon
Pelican Bay
State Prison
Crescent City
HWY 199
H
WY 101
H
WY 101
HWY 101
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1.2 Grant Funding Requirements
The City obtained 100% funding for this RWFS from a Water Recycling Funding Program Planning grant through the California State Water Resources Control Board (SWRCB) in September 2021 (Agreement No. SWRCB0000000000D2005002). The amount provided to complete this study is a $150,000 grant with a March 31st, 2024 deadline of completion. Funds may not exceed this amount under any circumstances and any work occurring after the work completion date will not be reimbursed under this Agreement. This study was completed in accordance with the Funding Agreement scope of work which includes the following:
1. Project management, quality assurance and quality control (QA/QC)
2. Background information collection
3. Recycled water market assessment
4. Treatment evaluation
5. Alternatives analysis
6. Recommended project plan
7. Construction financing plan and revenue program
8. Recycled water feasibility study report
The funding agreement is included in Appendix A for further detail.
1.3 Study Objectives
The purpose of this study is to evaluate the feasibility of producing and using recycled water locally, as a supplemental water source for the City, and to provide recommendations for recycled water projects that the City can pursue. The objectives also include:
1. Assessing beneficial reuse of wastewater as resource recovery,
2. Reducing potable water used for non-potable demands, and
3. Meeting the SWRCB grant requirements.
The steps taken to develop this study include the following:
1. Utilize existing information to develop a market assessment of potential recycled water uses in the City’s service area.
2. Explore options for beneficial reuse of industrial effluent from identified local industries.
3. Develop alternatives for production and distribution of recycled water or reuse of industrial effluent.
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4. Establish a comparison matrix to evaluate alternatives based on criteria important to the City and stakeholders.
5. Score and rank the alternatives based on quantitative and qualitative criteria to support the selection of a preferred alternative.
6. Develop an implementation plan that defines the design, financial and operation considerations for the preferred project(s).
1.4 Study Partners
Kennedy/Jenks Consultants, Inc. (Kennedy Jenks) has prepared this RWFS for the City on behalf of Stover Engineering. Kennedy/Jenks has collaborated with City staff, local industrial manufacturers, and public schools and recreational areas in the community to prepare this study, including:
• The City of Crescent City
• Crescent City Wastewater Treatment Facility (WWTF) Operators • Rumiano Cheese Company
Representatives from these entities have participated in key meetings and workshops to provide input on opportunities for potential production and utilization of recycled water in the region. The findings from this study were presented during a council meeting on September 19, 2022 to inform the public.
1.5 Relevant Studies
This work builds on previous planning documents prepared for the City. Table 1-1 lists some of the recent and relevant work that provides background information or has a nexus with this RWFS.
Table 1-1. Relevant Planning Documents
Document Agency
Reference(s)
(author date) Relevance to the RWFS
Engineering Report
on Production and
Use of Reclaimed
Water
Crescent City (Stover, 2011) Information on the feasibility of the production, transmission, and use of
reclaimed water, including water
quality requirements and facility
descriptions.
Waste Discharge
Requirements and
Water Recycling
Requirements
Crescent City (Regional Water
Board, 2017)
Order No. R1-2017-0002, NPDES
CA0022756. Details on the water
quality requirements for the effluent
from the WWTF.
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Reference(s)
(author date) Relevance to the RWFS
2020 Urban Water
Management Plan
Crescent City Freshwater
Environmental
Services
(UWMP, 2020)
Details on the water supply sources,
water delivery, demand
management measures, and water
shortage contingency planning for
the water service area.
Smith River Plain
Groundwater Basin
Information Sheet
California
Department of
Water Resources
(DWR
Bulletin 118,
2003)
Hydrogeologic and water quality
information on the Smith River Plain
groundwater basin.
Climate Change
Readiness Study
Crescent City (Kennedy Jenks,
2021)
An assessment of risk to
wastewater system infrastructure
due to climate change impacts and
provides suggested mitigation
measures.
Ranney Well
Evaluation Report
Crescent City (Layne, 2019) Provides information on the City’s existing Water Supply System and
Facilities
Del Norte Hazard
Mitigation Plan
Del Norte County (Del Norte
Hazard
Mitigation Plan,
2019)
Provides information for study area
characteristics of Del Norte County
Del Norte County,
Comprehensive
Economic
Development
Strategic Plan
Del Norte County (Del Norte
Economic Plan,
2020)
Provides information for study area
characteristics of Del Norte County
and Crescent City
Wastewater
Facilities Plan for
Crescent City
Crescent City (Facilities Plan,
2003)
Provides information on the City’s
existing wastewater system.
1.6 Study Organization
The RWFS is organized to align with the SWRCB Water Recycling Funding Program (WRFP) Guidelines – Division of Financial Assistance, Appendix B – Recommended Planning Outline for Water Recycling Projects. A summary is provided in Table 1-2 to indicate how and/or where each outline item is addressed in the report. Inclusion of the elements from the guidelines will also serve to facilitate future applications for funding through the State Revolving Fund (SRF) program.
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• Section 1: Introduction – provides background for the project, including goals and objectives and previous relevant studies this work builds on. • Section 2: Study Area Characteristics – describes the study area, major hydrologic features, water quality, land use, population projections and beneficial uses of receiving waters in Crescent City.
• Section 3: Treatment Requirements – discusses regulations guiding recycled water production, discharge, distribution, and use to protect public health, including the most recent regulatory landscape for potable reuse.
• Section 4: Water Supply Characteristics and Facilities – describes water supplies and uses, water supply reliability and future demands.
• Section 5: Wastewater Characteristics and Facilities – presents an overview of wastewater treatment facilities and wastewater quality. • Section 6: Recycled Water Market – identifies potential non-potable recycled water users within the City service area and estimates annual and peak demands for each user. Describes opportunities for potable reuse in Crescent City. • Section 7: Screening and Design Criteria Assumptions – describes the screening approach taken to select potential non-potable recycled water users. Identifies preliminary design criteria and cost assumptions used to size project facilities and develop planning-level cost estimates.
• Section 8: Project Alternatives Description – describes facilities and costs of each project alternative developed.
• Section 9: Project Alternatives Analysis – describes the screening criteria used to score and rank each project alternative. Presents the results of the scoring and ranking for each project alternative.
• Section 10: Recommended Project, Implementation Plan, and Operation Plan – describes the recommended project(s) based on the results of the scoring and ranking effort and input from the City. Provides an implementation and operations plan for the recommended project(s).
• Section 11: Construction Financing and Revenue Plan – presents funding and financing options for the proposed recommended project(s). Discusses potential pricing policies, funding opportunities, avoided costs and lost revenues to provide a more comprehensive view of the true cost and benefit of implementing recycled water use in Crescent City.
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Appendix A: SWRCB Funding Agreement
Appendix B: Recycled Water Uses Allowed in California Appendix C: Data Used for Analysis
C.1 WWTF Influent Flow Data
C.2 Crescent City Water Meter Data
C.3 Del Norte County Evapotranspiration and Crescent City Precipitation Data C.4 Treatment Sizing and Hydraulic Calculations
Appendix D: Engineer’s Opinion of Probable Costs
D.1 Engineer’s Opinion of Probable Costs
D.2 Project Alternatives Potable Water Cost Equivalents Appendix E: Project Alternatives and Detailed Scoring Evaluation E.1 Project Alternatives Matrix and Facilities
E.2 Scoring Criteria Guidelines
E.3 Scoring Results
Appendix F: Permitting Pathway Materials
F.1 SWRCB Order WQ 2016-0068-DDW: Water Reclamation Requirements for Recycled Water Use
F.2 Guidelines for the Preparation of an Engineering Report for the Production, Distribution and Use of Recycled Water (Title 22 Engineering Report) F.3 California Regional Water Quality Control Board North Coast Region Order No.
R1-2016-0002 General Waste Discharge Requirements for Discharges of Wine, Beverages and Food Processor Waste to Land in the North Coast Region Appendix G: Meeting Materials
G.1 Agendas, presentations and other materials from meetings, workshops, and webinars
Appendix H: Abbreviations
Table 1-2. Report Content Summary Per WRFP Recommended Outline App B*
Sec. # Title / Report Element Corresponding Report Location A Project Area
1 Detailed map(s) showing:
a Vicinity. Figure 1-1
b Relevant hydrologic (major streams, streams receiving waste discharges), geologic, and topographic features
Figure 2-1, Figure 2-3
c City boundaries. Figure 1-1, Figure 2-2
d Project site and service/study area boundary Figure 2-2 e Wholesale and retail water supply entity boundaries
within study area and adjacent to study area.
Figure 3-1
f Wastewater agency boundaries within and adjacent to
study area.
Figure 4-1
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Sec. # Title / Report Element Corresponding Report Location g Groundwater basin boundaries, Figure 2-3
h Existing recycled water distribution pipelines, storage, and users.
N/A– no current recycled
water users in the City
i Each recycled water facilities alternative, showing
approximate locations of distribution pipelines, storage, and potential users.
Figure 8-1, Figure 8-2,
Figure 8-3
2 Existing land use, trends, and projected land use. Section 2.4, Figure 2-4 3 Existing population, trends, and population projections of study area
Section 2.6
B Water Supply Characteristics and Facilities
1 Description of all wholesale and retail entities. Section 3.1 2 All sources of water for study area, major facilities, costs (fixed and variable), subsidies, and customer prices.
Section 3.2, Section 3.3,
Section 3.4
3 Beneficial uses of receiving waters, degree of use, and portion of flow that is effluent.
Section 2.7
4 Capacities of present facilities, existing flows, estimated years when capacities will be reached for existing major components (water treatment plants, major transmission, and storage facilities).
Section 3.3
5 Groundwater basins; including quantities extracted by all users, natural and artificial recharge, losses by
evapotranspiration, inflow and outflow of basins, and safe yield or overdraft.
Section 3.2
6 Water quality of groundwater and surface water. Section 2.4, Section 3.6 7 Water use trends, future demands, prices, and costs. Section 3.5 8 Sources for additional water and plans for new facilities (for both the local entity and the wholesalers).
Section 3.7
C Wastewater Characteristics and Facilities
1 Description of entities. Section 4.1
2 Description of existing facilities, including treatment/reuse processes and schematic(s), design criteria, current
capacities, current flows, current water quality
characteristics and beneficial uses of the water resources affected by the facility, and the current discharge
location(s).
Section 4.1
3 Wastewater treatment process schematics (existing and proposed) and flows for each stage of treatment (primary, secondary, and tertiary/advanced).
Section 4.1
4 Description of current system users (% residential,
commercial, industrial, etc.).
Section 4.1
5 Water quality of effluent and any seasonal variation. Section 4.3, Section 4.4 6 Additional facilities needed to comply with waste
discharge requirements.
Section 4.5
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Sec. # Title / Report Element Corresponding Report Location 7 Sources of other problem constituents and control
measures.
Section 4.3
8 Existing water recycling users, quantities, and contractual arrangements.
N/A – no current
recycled water users in
the City
9 Existing water rights for use of treated effluent after discharge.
Section 4.1
10 Wastewater flow variations, hourly and seasonally Section 4.4 11 Description of the current asset, operation, and
maintenance management systems used at the treatment
facilities.
Section 4.2
D Treatment Requirements for Discharge and Reuse
1 Future flow increases or other changes to the influent wastewater characteristics.
Section 4.1, Section 4.4
2 Required water qualities for potential uses. Section 5.3 3 Required health-related water qualities or treatment
requirements for potential uses, operational and on-site requirements (backflow prevention, buffer zones, dual
plumbing, etc.).
Section 5.2
4 Wastewater discharge or reuse requirements and
anticipated changes in requirements.
Section 5.2
5 Water quality-related requirements of the RWQCB to
protect surface or groundwater from problems resulting
from recycled water use.
Section 5.2
E Recycled Water Market
1 Description of market assessment procedures. Section 6 2 Definition of logical service area based on results of market assessment.
Section 6
3 Descriptions of all users or categories of potential users, including (a) type of use, (b) expected annual recycled water use, (c) peak use, (d) estimated internal capital investment required (on-site conversion costs), I necessary water cost savings, (f) desire to use recycled water, (g) date of possible initial use of recycled water, (h) present and future source of water and quantity of use, (i) quality and reliability needs, and (j) wastewater disposal methods.
Section 6.1
4 Summary tables of potential users and related data. Section 6.1 F Project Alternative Analysis
1 Planning and design assumptions Section 7.1
a Delivery and system pressure criteria. Section 7.1
b Peak delivery criteria. Section 7.1
c Storage criteria. Section 7.1
d Planning period over which a water recycling project is evaluated.
Section 7.1
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Sec. # Title / Report Element Corresponding Report Location 2 Water Recycling Alternatives to be Evaluated Section 8 a Alternative markets: Section 8
i Based on different levels of treatment. Section 8
ii Based on Geographical areas. Section 8
b Treatment alternatives: Section 8
i Alternative levels of treatment. Section 8
ii Alternative unit processes to achieve a given level of treatment.
Section 8
iii Plant treatment process prior to construction. Section 4.1 Iv Class of plant prior to and after construction (i.e. Class I, II, III, IV, or V).
Section 8
c Pipeline distribution alternatives. Section 8
i Route alternatives. Section 8
ii Pipeline lengths, diameter, and material. Section 8
iii Quantity of service laterals and meters to be installed. Section 8 d Storage alternatives: Section 8
i Location, type, and material. Section 8
ii Storage analysis using diurnal flows. Section 8
e Pump/lift station alternatives: Section 8
i Provide reason for new pump station and/or upgrades. Section 7, Section 8 ii Describe pump types, proposed well design, and proposed components (i.e. debris structure, SCADA controls, backup power, etc.)
Section 8
iii Provide flow design criteria (average daily flow, peak hour flow, proposed flow for future growth projections) and
pump curves.
Section 7.1
f Sub alternatives of selected alternative: N/A – no sub alternatives i Marginal analysis for selected alternative for certain categories of users or certain geographic areas.
N/A
ii Use of water blending during peak irrigation months. N/A 3 Non-recycled water alternatives. Section 3.7
a Discussion of other potentially viable new sources of water. Section 3.7 b Provide economic costs. Section 3.7
4 Water conservation/reduction analysis. Section 3.7
a Description of analysis. Section 3.7
b Impact on recycling, if any. Section 3.7
c Recommendation. Section 3.7
d Implementation. Section 3.7
5 Pollution control alternatives, if applicable, needed to comply with waste discharge requirements, and
possible allocation of costs between recycling and
pollution control.
Section 11.3
6 No project alternative. Section 9.4
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Sec. # Title / Report Element Corresponding Report Location 7 Information supplied for each alternative to include, but not be limited to:
a Cost tables for each alternative with breakdown of costs by total capital (without grants), O&M, unit processes, and with equivalent annual cost and per acre-foot cost.
Section 8
b Lists of potential users assumed for each alternative. Section 8 c Economic analysis in dollars per acre-foot of recycled water produced or delivered
Section 8
d Energy analysis, including direct and construction energy. Section 9 e Water quality impacts:
i Effect on receiving water by removing or reducing
discharge of effluent, including effect on beneficial uses resulting from reduced flow.
Section 2.7, Section 11.2,
Section 10.2
ii Ground water impacts. Section 10.2
8 Comparison of above alternatives and recommendation of specific alternative.
Section 7, Section 8,
Section 9
a Discussion of beneficial and adverse environmental
impacts on the existing environment, future environment, and individual sensitive environmental issues identified through project management or public participation.
Section 7.1.5
b Analysis of direct, indirect, and cumulative impacts on sensitive environmental resources.
Section 7.1.5
c Appropriate mitigation measures not already included in the proposed action or alternatives, to mitigate adverse environmental impacts.
Section 7.1.5
d Thorough discussion of the environmental reasoning for selection of the chosen alternative for the project.
Section 7.1.5
9 Comparison of above alternatives and recommendation of specific alternative.
Section 9
G Recommended Project
1 Description of all proposed facilities and basis for selection. Section 8 2 Preliminary design criteria Section 7
3 Cost estimate based on time of construction.(a) Selected project alternative total cost (b) Cost index (c) Discount rate. (d) Useful life (years) I Life cycle costs (present worth included O&M costs) (f) Operations and maintenance yearly costs (g) Replacement costs.
Section 8
4 List of all potential users, quantity of recycled water use, peak demand, and commitments obtained.
Section 8, Section 10
5 Reliability of facilities as compared to user requirements. Section 8 6 Implementation plan: Section 10
a Coordination with water suppliers, determination of recycled water supplier and needed agreements or ordinances.
Section 10.2.1
b Commitments from potential users and ability and timing of users to join system and make on-site investments
Section 10.2.2
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Sec. # Title / Report Element Corresponding Report Location c Tentative water recycling requirements of RWQCB. Section 10.2.3 d Commitments from potential users. Section 10.2.4
e Water rights impact. Section 10.2.5
f Permits required for project implementation Section 10.2.6 g Detailed schedule including, but not limited to, notice-to proceed, construction completion, initiation of operations, etc.
Section 10.2.7
7 Operational plan – responsible people, equipment,
monitoring, irrigation scheduling, etc.
Section 10.3
8 Description of any key issues to be resolved, particularly items that may significantly impact the project budget or schedule.
Section 10
H Construction Financing Plan and Revenue Program
1 Sources and timing of funds for design and construction. Section 11.1 2 Pricing policy for recycled water. Section 11.2
3 Costs that can be allocated to water pollution control. Section 11.3 4 Annual projection of: Section 11.4
a Water prices for each user or category of users. Section 11.4.1 b Recycled water used by each user. Section 11.4.2
c Annual costs (required revenue) of recycling project. Section 11.4.3 d Allocation of costs to users. Section 11.4.4
e Unit costs to serve each user or category of users. Section 11.4.5 f Unit price of recycled water for each user or category of users.
Section 8, 9.4
g Sensitivity analysis assuming portion of potential users fail to use recycled water.
Section 11.4.6
5 Sunk costs and indebtedness. Section 11.5
J Appendices
1 Tables of all abbreviations. Appendix H:
2 Copies of letters of interest or intent from recycled water users, or other documentation of support from potential users.
The potential user for the
RW is the City.
3 Draft of recycled water mandatory use ordinance or model user contract.
Ordinances/contracts will
be developed if non-City
users are identified.
4 Drafts of necessary agreements, such as wholesale-retail agreement, joint powers agreement
Agreements will be
developed as needed
5 Hydraulic calculations, model output summaries, other related conclusion supporting information.
Appendix C.4
* WRFP Guidelines Appendix B – Recommended Planning Outline for Water Recycling Projects
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This section provides a description of study area characteristics, including project setting, hydrologic features, groundwater basins, water quality, land use, and population projections.
2.1 Project Setting
2.1.1 Del Norte County
The City of Crescent City is located along the Pacific Ocean in Del Norte County, the northernmost coastal county in California. Del Norte County (County) is primarily rural and includes the Smith River, Jedediah Smith Redwoods State Park, Del Norte Coast Redwoods State Park, Siskiyou Wilderness, and miles of coastline along the Pacific Ocean. The Smith River valley offers rich agricultural lands and a year-round growing season. Most of the County’s population of 28,1001 resides in the urban service area of Crescent City, which also hosts most of the County economic activity, except for Del Norte County Regional Airport, which is outside the City limits. The remainder of the County’s 1,230 square miles is mountainous, with extensive Public and Tribal lands and few roads (Del Norte Economic Plan, 2020). Access to Crescent City is limited to Highway 101 from the south, which crosses Last Chance Grade, an area of geologic instability, or US 199 from the north, which does not currently allow access by large trucks. Del Norte County climate is characterized by moderate temperatures and significant precipitation in the range of 96 to 150 inches, the majority occurring between October and April (Del Norte Hazard Mitigation Plan, 2019). Most of the precipitation falls as rain, except at high altitudes where some may fall as snow. Temperatures along the coast are relatively consistent, with only 10 degrees variation from summer to winter, while the inland areas have a greater temperature range. Overall, the average summer temperature in the County is 69ºF in July and the average winter temperature is 38.5 ºF in January (Del Norte Hazard Mitigation Plan, 2019).
2.1.2 City of Crescent City
The City of Crescent City is located approximately 15 miles south of the Oregon border. It is the only incorporated city in Del Norte County and has an area of approximately 1.4 square miles.
The City is in a coastal terrace area with slopes gently declining south towards the harbor and declining east toward Elk Creek. Elevations within the City range from 0 to 50 feet above mean sea level (UWMP, 2020). A map of the topographic contours within the area are shown on Figure 2-1. The population is estimated to be 6,673 in 2020, a decrease from the 7,643 in the 2010 census (U.S. Census Bureau, 2022; Del Norte Economic Plan, 2020). 1 https://www.census.gov/quickfacts/delnortecountycalifornia "J
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Figure 2-1
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Scale: Feet
Legend
"J City Pump Station
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Source: Esri, Maxar, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community Beachfront
Park
Crescent
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Harbor
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Elk Creek
Battery Point
Lighthouse
Highway 101
Highway 101
B Street
Battery Street
Front Street
Crescent City Recycled Water Feasibility Study (RWFS) Page 15 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx The climate in Crescent City is moderate, with cool summers due to moderating influences of the ocean. Winter rains are reflective of the City’s location in the Pacific Northwest. Sunshine is limited during the summer due to coastal fog and the temperatures are seldom higher than 80oF. The wintertime temperature seldom drops below 25 ºF and conditions include frequent heavy rain with occasional strong winds (Facilities Plan, 2003). The average summer temperature is between 60 and 70 degrees while the average winter temperature is 40 to 50 degrees (Facilities Plan, 2003). Snow is rare in the city due to its coastal location but is common at inland elevations of Del Norte County. The average annual precipitation is
71.3 inches, with the majority of rainfall occurring between the months of October and April (UWMP, 2020). The average yearly wind speed is 9 miles per hour (mph), but during extreme winter storm events, prevailing winds can reach 70 to 90 mph (Facilities Plan, 2003). Recent data of the average annual evapotranspiration is approximately 38.50 inches, with monthly evapotranspiration rates of four to five inches in the summer months (CIMIS Smith River Station). Recent data, included in Table 6-2 and Appendix C, shows monthly average precipitation exceeds monthly average evapotranspiration during most months, reducing the risk and concern for drought conditions and water scarcity in Del Norte County.
Crescent City is located near three faults, the Bald Mountain-Big Lagoon fault, the Cascadia Subduction Zone fault, and the Trinidad fault, making it at risk for earthquake and local tsunami events. The soil in the Crescent City area is also classified as a “soft soil”, which means it is at an increased risk of liquefaction (Del Norte Hazard Mitigation Plan, 2019). Due to its location near the southern end of the Cascadia Subduction Zone, the City is particularly vulnerable to tsunami damage from distance events (such as earthquakes in Alaska or Japan).
2.1.3 Study Area Boundaries
The study area boundary for this RWFS is delineated in Figure 2-2. The study area boundary selected is the water service area for Crescent City. The study area was selected to capture potential users of recycled water both within and outside of the City limits. The study area encompasses the major irrigation areas within the vicinity of the WWTF, as well as industrial manufacturers in the area.
2.2 Surface Hydrology
All surface water within the study area generally flows to the Pacific Ocean. One surface water body, Elk Creek, is within the study area. The creek discharges into the Pacific Ocean and is not used as any source of water supply. The City’s water system relies entirely on groundwater associated with the Smith River Plain Groundwater Basin (SRPGB) as its source of water. The Smith River drainage basin covers approximately 700 square miles and produces runoff of about 2.9 million acre-feet per year (MAFY), making it the highest water-producing drainage basin in California based on runoff per square mile (UWMP, 2020). The City’s water intake on the Smith River is located about 8.5 miles from the City limits and further described in Section 3.3 of this report.
Q3
³ 0 2,000 4,000
Scale: Feet
City of Crescent City
Crescent City, CA
Recycled Water Study
Area Boundary
K/J 2076056*00
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Figure 2-2
Z:\Projects\CityOfCrescentCity\Events\20211013_RWFS\Fig2-2_RecycledWaterStudyAreaBoundary.mxd Date: 8/10/2022 Printed by: MaryEllenMcCarty Legend
Water Service Area/Recycled Water Study Area Boundary
City of Crescent City Boundary
Q3 Wastewater Treatment Facility
Force Pressure Line
Source: Esri, Maxar, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community Outfall
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2.3 Groundwater Basin
The majority of Del Norte County and all of Crescent City overlays the SRPGB. A map showing the boundary of the SRPGB is included in Figure 2-3. The groundwater basin is approximately 63 square miles in size and is bounded to the north and east by the Del Norte fault (DWR Bulletin 118, 2003). The north end of the basin narrows at the mouth of the Smith River to a marine terrace less than one mile wide that continues into Oregon. The basin is bounded to the north, east, and south by the Mesozoic Franciscan Formation (DWR Bulletin 118, 2003). The basin is an emerged low-relief marine terrace and the surface of the plain is comprised of sand dunes, floodplain deposits, unconsolidated river terrace deposits, and surface exposures of the marine Battery Formation (DWR Bulletin 118, 2003). Underlying the terrace deposits are the marine Battery Formation and the St. George Formation (DWR Bulletin 118, 2003). Beneath the St. George Formation is basement rock of the Jurassic-Cretaceous Franciscan Complex (DWR Bulletin 118, 2003).
Recharge in the basin occurs via direct infiltration of precipitation, subsurface inflow from surface water and precipitation infiltration of alluvial fans or dune areas, and infiltration of runoff in the lower reaches of the Smith River and other permeable stream channels (DWR Bulletin 118, 2003). Generally, groundwater level data show a seasonal fluctuation of approximately 5-15 feet for normal and dry years and there does not appear to be any long-term increasing or decreasing trends in groundwater levels. Estimates of groundwater extraction from a 1996 survey are 12,000 and 990 AF for agricultural and municipal/industrial uses, respectively (DWR Bulletin 118, 2003).
As of the DWR Groundwater Bulletin 118, 2020 update, the SRPGB is considered a very low priority basin and is not required to develop a groundwater sustainability plan.
2.4 Water Quality
2.4.1 Groundwater Quality
Groundwater in the SRPGB is generally of high quality, consisting of magnesium bicarbonate and magnesium-sodium bicarbonate type waters. Increasing proportions of sodium and chloride are found in waters from the southern half of the basin (DWR Bulletin 118, 2003). Total dissolved solids (TDS) range from 50 to 500 mg/L, with an average of 100 mg/L (DWR Bulletin 118, 2003). High levels of iron can be found in some areas and locally high chloride, calcium, and TDS areas are also present.
As mentioned previously, the City relies entirely on the groundwater of the Smith River for its source of water. The City captures groundwater using a Ranney Well described in more detail in Section 3.3.1 and the City’s only extent of treatment is chlorination. Crescent City’s annual 2021 Consumer Confidence Report indicated high drinking water quality. Table 2-1 summarizes drinking water sampling results.
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Maximum
Contaminant
Level (MCL)
Sodium (ppm) 1.8 None
Hardness (ppm) 66 None
Nitrate Not Detected 10
Iron Not Detected 0.3
Manganese Not Detected 0.05
Aluminum Not detected 1
Magnesium 12 None
Calcium 6.2 None
Chlorine Residual 1.15 N/A
pH 7.8 N/A
Turbidity 0.18 5.0
Source: Crescent City 2021 Annual Water Quality Report
2.4.2 Surface Water Quality
The City’s water supply is groundwater as discussed above, therefore surface water quality is not covered in this study.
³
Z:\Projects\CityOfCrescentCity\Events\20211013_RWFS\Fig2-3_GroundwaterBasinRev.mxd Date: 8/10/2022 Printed by: MaryEllenMcCarty Legend
Smith River Plain
Groundwater Basin Boundary
City of Crescent City
Boundary
PreQuaternary Fault, certain
PreQuaternary Fault, approx.
located
PreQuaternary Thrust Fault,
certain
PreQuaternary Thrust Fault,
approx. located
Quaternary Thrust Fault,
certain
Soil Type
Alluvium
Blueschist
Conglomerate
Dune Sand
Mafic Volcanic Rock
Sandstone
Serpentinite
Source: Esri, Maxar, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community 0 6,000 12,000
Scale: Feet
City of Crescent City
Crescent City, CA
K/J 2076056*00
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Smith River Plain
Groundwater Basin Boundary
and Geologic Features
Figure 2-3
Note:
Soil types were obtained from USDA/NRCS National Soil Survey.
Fault Lines were obtained by California Geological Survey.
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2.5 Land Use
Figure 2-4 shows the City of Crescent City 2001 General Plan Land Use Diagram. The Crescent City planning area is defined by an east west line coinciding with Blackwell Road, following south along Elk Valley Road, and then following the Federal and State lands on the east as shown in Figure 2-4. Within the planning area, Crescent City has defined an urban boundary that includes all land considered for future water and sewer service expansion and thus, for future urban development and annexation. Development beyond the urban boundary is prohibited because it is considered a low-density area and would be costly to build water and wastewater service infrastructure. The urban boundary line is also included on Figure 2-4. The majority of the City is comprised of residential land use, followed by commercial and industrial land use.
For the development of the 2020 UWMP, the City contacted the Del Norte County Community Development Department (CDD) regarding any large planned residential developments, buildouts, or additions to the water system over the next 25 years in unincorporated areas adjacent to the City limits. The CDD indicated that there were no large developments or additions planned that would impact the Crescent City water system.
2.6 Population Projections
Based on GIS analysis of 2010 U.S. Census data at the block level, the population of the Crescent City water service area was 17,840 persons, including the Pelican Bay State Prison population. The City population was estimated to be 6,673 in 2020, a decrease from the 7,643 in the 2010 census (U.S. Census Bureau, 2022; Del Norte Economic Plan, 2020). Population projections for 2021-2045 were completed for the 2020 Urban Water Management Plan using California Department of Finance data. The projected population growth rates for the planning period are included in Table 2-2 below.
Table 2-2. Projected Population Growth Rate for 2021 to 2045 2021-2025 2026-2030 2031-3025 2036-2040 2041-2045
-0.49% -0.54% -0.45% -0.36% -0.27%
6,511 6,337 6,196 6,085 6,003
Source: Growth rates from UWMP, 2020.
2.7 Beneficial Uses of Receiving Waters
The Water Quality Control Plan for the North Coast Region (Basin Plan) contains the beneficial uses of receiving waters in the North Coast Region, including the Crescent City region (NCRWQCB 2018). The Basin Plan provides water quality control planning, sets water quality objectives for the North Coast Region, and identifies the beneficial uses of waters of the State within its jurisdictional area. The Basin Plan also incorporates the Water Quality Control Plan for the Waters of California (Ocean Plan).
Effluent from the City WWTF, treated to secondary standards, is discharged via an ocean outfall pipeline to the Pacific Ocean, shown on Figure 2-2. Local stormwater runoff flows into surface water which ultimately drains to the Pacific Ocean.
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Table 2-3. Beneficial Uses of the Receiving Waters for the City WWTF Effluent Beneficial Uses Crescent City Harbor Pacific Ocean
Aquaculture Existing Existing
Preservation of Areas of
Special Biological Significance
Existing
Cold Freshwater Habitat Existing
Commercial and Sport Fishing Existing Existing
Estuarine Habitat Existing
Freshwater Replenishment Existing
Industrial Process Supply Existing
Industrial Service Supply Existing
Marine Habitat Existing Existing
Migration of Aquatic
Organisms
Existing Existing
Navigation Existing Existing
Non-Contact Water Recreation Existing Existing
Rare, Threatened, or
Endangered Species
Existing Existing
Shellfish Harvesting Existing Existing
Spawning, Reproduction,
and/or Early Development
Existing
Warm Freshwater Habitat Potential
Water Contact Recreation Existing Existing
Wildlife Habitat Existing Existing
Source: NCRWQCB 2018
LAKE EARL
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20 - Pelican Bay State Prison19 - Crescent City Municipal Wastewater Treatment Plant18 - Convention Center16 - Crescent Elk School 5 - Pine Grove School4 - Mary Peacock School3 - County Landfill (Crescent City Landfill)2 - County Airport (McNamara Field)1 - County Park (Point St. George Access) 15 - Joe Hamilton School14 - Public Utility Center13 - County Park (Pebble Beach Access)11 - Juvenile Detention Facility10 - Bess Maxwell School 9 - City Water Storage Tank8 - Crescent Fire/Emergency Services Center7 - Del Norte High School6 - Community College (College of the Redwoods) 17 - County Park (Macken Ballfields)12 - Del Norte County Fairgrounds Public Facilities Index
Crescent City City Limit
Planning Area Boundary
Urban Boundary
Coastal Zone Boundary
Single Family (0-2)Single Family (2-6)Multi-Family (6-15)Multi-Family (15-30)Mobilehome Park Residential
Business-ProfessionalVisitor and Local CommercialGeneral Commercial Commercial
General IndustrialLight Industrial
Industrial
Public
Public Facilities and Tribal Lands
County Rural DevelopmentCounty Resources
Countywide Designation
Harbor RelatedHarbor DependentHarbor Dependent RecreationHarbor Dependent Commercial Harbor
Open SpaceNatural Resources
Conservation and Open Space
Urban Reserve Overlay
Overlays
1 inch = 2750 feet
Prepared by:
City of Crescent City
General Plan
Land Use Diagram
May 21, 2001
N
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2000 0 2000 4000 6000 Feet
/(101
Lake
Earl
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1 inch = 5,000 feet
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500 0 500 1000 1500 2000 Feet
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Southern Planning
Area Boundary
Crescent City Land Use Designations
1 inch = 2750 feet
1 2
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City of Crescent City
Crescent City, CA
General Plan Land Use Diagram
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Figure 2-4
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This section provides an overview of the City’s current water supply characteristics and facilities.
A more detailed description of the City’s water system can be found in the 2020 Urban Water Master Plan prepared by Freshwater Environmental Services.
3.1 Wholesale and Retail Entities
The City of Crescent does not rely on a wholesale agency for a source of potable water supply and is not a wholesale provider of water (UWMP, 2020). As of the 2020 UWMP, there are no plans to acquire water from wholesalers or other sources through 2045. The City is an urban retail water supplier that owns and operates a public water system. The City supplies water to a population of approximately 17,840, which includes customers in the urban service area within the City’s jurisdictional area, three water districts, and Pelican Bay State Prison (UWMP, 2020).
The three water districts served potable water by the City are Meadowbrook, Church Tree Community Service District, and Bertsch Ocean View Community Services District (UWMP, 2020). The districts hire the City crews and staff by contract to maintain their system and perform billing and accounting. Crescent City’s water service area and existing hydraulic profile can be found on Figure 3-1 and Figure 3-2, respectively.
3.2 Source of Water
The City’s sole water source is the groundwater underflow of the Smith River associated with the SRPGB. Water is pumped via a Ranney collector well as described in Section 3.3.1.
BOV Tank
Wigley Tank
Amador Tank
Elevated Tank
Washington Tank
Church Tree Tank
Control Building
Ranney Collector
Chlorine Building
Booster Station #1
Elk Valley Pump Sta.
City of Crescent City Water System
BOV (Bertsch-Ocean View)
Water District
City Connections
Churchtree Water District
Meadowbrook Water District
County Connections
Pelican Bay
State Prison
0 2,500 5,000 10,000
Feet
Legend
City Limits Boundary
Place of Use Boundary
Booster
Chlorine Facility
Control
Ranney
Water Tank
Pump
Map by: F. Ludemann
City of Crescent City 12/2008
City of Crescent City
Crescent City, CA
Existing Water System Map
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Figure 3-1
Figure 2-1: System Hydraulic Profile December 2021
450
400
350
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50 0 Elevation (ft)
BOV
Tank
Amador
St.
Reservoir
Church Tree
Tank
Wigley
Tank
Ranney
Well Ranney
PS
Meadowbrook
Water
District
Churchtree
Water
District
North
Crescent
City
Central
Crescent
City
Bertsch-Ocean
View Water
District
HWL 376'
0.05 MG
HWL 409'
0.03 MG
Church
Tree PS
Pelican
Bay State
Prison
Washington
PS
HWL 86'
4.0 MG
Amador
PS
Elk Valley PS
HWL 90'
1.5 MG
HWL 263'
0.75 MG
PRV Facility /
Elevated Tank
Elevated
Tank
HWL 210'
0.05 MG Washington
Blvd.
Reservoir
Booster
Station #1
Wigley
PS
Q:\Eugene\2019\1976002.03_Stover_TaskOrder3_WaterModel\Section_9_Report_Preparation\9.03_Calculations\Hydraulic Profile Figure 2-1: System Hydraulic Profile Existing Water System
Hydraulic Profile
Figure 3-2
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City of Crescent City
Crescent City, CA
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3.2.1 Groundwater Management
Per the Groundwater DWR Bulletin and 2020 UWMP, groundwater levels typically fluctuate seasonally and range from 5-15 feet below ground surface. Decreasing water levels are not predicted for the SRPGB.
Although groundwater is in abundant supply, the amount of groundwater the City can currently extract is regulated under the following permit and summarized in Table 3-1. Maximum Permitted Pumping Rates (UWMP, 2020):
1) City of Crescent City State Water Resources Control Board Water Rights Permit # 11475.
Of the 1,194 MGY, Pelican Bay State Prison (State Department of Corrections) is entitled to 347 MGY as part of the City’s permit. Pelican Bay State Prison purchases water from the City and the City reports the diversion and usage amount for the prison.
Table 3-1. Maximum Permitted Pumping Rates
Entity Permit #
Max Pumping
Rate (cfs)
Max Pumping
Rate (MGD)
Max Annual
Production
(AFY)
Max Annual
Production
(MGY)
City of Crescent
City 11475 12.8 8.2 3,666 1,194
Source: UWMP, 2020
Crescent City has never exceeded their pumping limit for groundwater extraction. The historic volume of groundwater produced by the City of Crescent City has been below 1,000 MGY (UWMP, 2020).
As of the 2020 update of the DWR Groundwater Bulletin 118, the SRPGB is considered a very low priority basin and is not required to develop a groundwater sustainability plan. A Groundwater Management Plan has not been developed for the SRPGB (UWMP, 2020).
Overdraft, a condition in which the amount of groundwater withdrawn by pumping over the long term exceeds the amount of water that recharges the basin, is not considered an issue for the SRPGB. The SRPGB is not being over-drafted based upon extraction rates, cone of depression, recharge rate, and water surface elevation and not likely to become over-drafted if present management conditions continue (UWMP, 2020).
3.3 Current Water Supply Facilities
The City’s water supply facilities consist of water transmission mains ranging from 12 to 24 inches, a Ranney collector well, storage reservoirs, a chlorination building, and pump stations. The City’s current water supply facilities were originally constructed in 1958 (UWMP, 2020). Improvements to existing facilities were made in the late 1980’s and early 2000’s (UWMP, 2020). The City’s major water supply facilities and capacities are described in the following sections and can be seen on Figure 3-1. A hydraulic profile of Crescent City’s water system can be seen on Figure 3-2.
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3.3.1 Ranney Well Collector
Water is collected from the groundwater underflow of the Smith River via a well point type structure known and patented as a “Ranney Well.” The well collector is located on the riverbank approximately 8.5 miles north of the City limits and is capable of producing approximately 6,700 AFY (2,181 MGY) (UWMP, 2020). The Ranney well consists of a 13-foot internal diameter of reinforced concrete caisson that is about 52.5 feet in length from the pump room floor to the top of the bottom plug (Layne, 2019). The well is equipped with eight 8-inch diameter carbon steel punch slotted laterals used to convey groundwater into the caisson (Layne, 2019).
Three 125 horsepower (hp) vertical turbine pumps are located inside the Ranney Collector Well.
Two Ranney Collector pumps were replaced in 2021 excluding their motor. Each pump has a capacity of approximately 1,680 gallons per minute (gpm) at 235 feet of total dynamic head (TDH). Field pump flow indicated that the three pumps together can provide flow of 6.0 to
6.2 MGD (UWMP, 2020). Variable frequency drives were added to the pumps in 2011. A new water system control and data acquisition (SCADA) system was installed in 2020.
3.3.2 Distribution System and Storage Reservoirs
Water is pumped from the collector well through dual 14-inch and 18-inch transmission mains to a chlorination facility off Kings Valley Road about one mile south of the Smith River. The chlorination building houses dual chlorinators, a chemical storage area, and an emergency power generator. After the chlorination facility, the 14-inch transmission main continues to the 50,000-gallon Elevated Reservoir, which serves to maintain the hydraulic grade line for the City’s service area, and pressure control facility near Highway 101 and Wonderstump Road.
The City plans to remove the elevated tank from service due to seismic design deficiencies once the pressure reducing station is operating. The 18-inch transmission main continues to supply the Pelican Bay State Prison. From the Elevated Reservoir, water flows by gravity approximately two miles through a 24-inch water transmission main and a 12-inch transmission main to the City’s distribution system and storage reservoirs (UWMP, 2020).
The first Washington Boulevard storage reservoir and pumping facility was constructed in 1963.
In 2001, the original storage reservoir was replaced with a 4-million-gallon (MG) reservoir. The upgrade equalizes supply and demand, provides sufficient supply for fire protection, and furnishes supply during periods of maintenance and repair. The two pumps within the facility were also replaced in 2001 by three 75-hp pumps to maintain adequate pressures within the distribution system. A new auxiliary power system was also installed.
The Amador storage reservoir and pumping facility was originally installed in 1982 to increase the volume of storage and to improve system pressures, flows, and fire demands within the system. Three identical 75-hp pumps were installed at this facility and auxiliary power is provided by a 300 kW Onan generator. The Amador storage reservoir has a total capacity of
1.5 MG, but is operated at an effective capacity of 1.0 MG. Both the Amador and Washington Blvd facilities are controlled by the SCADA system with operator adjustable setpoints. The Amador facility is currently undergoing a two-phase, multi-year renovation project. Within the City’s distribution system, approximately 4,600 linear feet of 16-inch high-pressure distribution lines were added between 2000 and 2002.
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3.4 Water Fees
The City of Crescent City customers are metered and pay a flat fee of $22.49 for potable water usage up to 500 cubic feet (cf). For every 100 cf above the 500 cf limit, an additional charge of $2.62 is imposed ($2.06 for Church Tree)2. The three water districts are also subject to Special District fees: $9.75 for Bertsch Oceanview, $15 for Church Tree, and $4.50 for Meadowbrook.
3.5 Historical and Projected Water Use Trends
Historically, all of Crescent City water demand have been met with potable water, and there have been no shortages in the water supply for the City. The City of Crescent City provides potable water supply to the following sectors:
• Single family residential
• Commercial/Institutional (includes multi-family)
• Industrial
• Single Prison Connection
A breakdown of water use volume for each sector from 2015-2020 is presented in Table 3-2. As shown in the table, the average total water use is 803 MG, or approximately 2,465 AFY. This is less than half the available water supply of 6,700 AFY and well within the extraction limits under the state permit of 3,666 AFY mentioned in Section 3.2.1.
Table 3-2. 5-Year Average Water Use by Sector from 2015 to 2020 5-Year Average Volume
(MGY) % of Total Volume
Residential 242 30%
Commercial/Institutional 222 28%
Industrial 6 0.75%
Prison 159 20%
Distribution Loss 174 22%
Total 803 100%
Source: UWMP 2020
The 2020 Urban Water Master Plan evaluated current water use (for 2020) and projected water demands through 2045. Single family residential water use projections were decreased to align with the annual percent population reduction described in Section 2.6. Commercial, institutional, and industrial water demands were projected to be maintained for the planning period.
Distribution losses were projected to be 23% of the total water production volume. The projected annual water use demand by customer category is included in Table 3-3 below. As shown in the table, the average total water use by 2045 is projected to be 786 MG, or approximately 2 https://www.crescentcity.org/departments/WaterandSewer/WaterServiceAreasandFees Crescent City Recycled Water Feasibility Study (RWFS) Page 29 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx 2,412 AFY. This is less than half the available water supply of 6,700 AFY and within the permit limits, therefore potable water supply is sufficient to meet the projected annual water demand.
Potable water storage is not a concern for the City as water use demand is projected to decline and is well within the rights of the permits discussed in Section 3.2.1.
Table 3-3. Projected Annual Water Use Demand by Customer Category Water Use (MG)
2025 2030 2035 2040 2045
Single Family Residential 236 230 225 221 218
Commercial 222 222 222 222 222
Industrial 6 6 6 6 6
Institutional/Governmental 159 159 159 159 159
Losses 186 184 183 182 181
Total 809 801 795 790 786
Source: UWMP 2020
3.6 Quality of Water Supplies
Quality of the groundwater underflow of the Smith River was discussed previously in Section 2.4.2. The groundwater produces an abundant supply of high-quality freshwater and requires minimal water treatment before it enters the distribution system. The groundwater is disinfected in the chlorination building as mentioned in Section 3.3.2. The raw groundwater is disinfected with liquid sodium hypochlorite via two dosing pumps at the chlorination building located one mile south of the Ranney well collector. The City does not intend to upgrade water treatment facilities or construct a water treatment plant as long as water quality remains adequate for potable use.
3.7 Potential Future Water Sources
The City has adequate water supply with the current permit limits to supply future populations and expected water demand. The City does not need imported water. There are no potential economically feasible or necessary potential future water sources beyond recycled water being considered for the region. However, the City is performing a feasibility study for a redundant well near the chlorination building.
The City’s existing Wastewater Treatment Plant does have the capability of producing tertiarytreated recycled water, which is described in detail in Section 4.1.2.4. Recycled water uses within Crescent City are explored and outlined in later sections of this report.
3.7.1 Water Conservation Efforts
While not considered a “source” of potable water, water conservation efforts can reduce the demand for potable water and increase the volume of available water supply. The City currently Crescent City Recycled Water Feasibility Study (RWFS) Page 30 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx has water demand management measures in place to effectively regulate water use and identify water losses. These management measures include the following:
1) Conservation Pricing: In September 2013, the City completed a rate study and approved a new rate structure that utilizes a uniform rate and results in conservation pricing (UWMP, 2020). A new rate study to enhance the 2013 conservation pricing was started and is currently ongoing.
2) Metering: All City customer sectors are metered separately for single-family residential, commercial, industrial, and educational facilities.
3) Assessment of Distribution System Real Loss: The City completes AWWA Water Loss Audits on an annual basis and focuses on leak repair efforts based on the audit results. The City also routinely measures and records production rates, receiving rates, and delivery using totalizers connected to the City’s control system.
Efforts to promote water conservation and reduce water demand have been made on behalf of the City through public education and outreach. The City has initiatives to inform the public about water conservation using webpages, public announcements, public meetings, and water user reports. More detail regarding water conservation efforts can be found in the 2020 UWMP.
Crescent City Recycled Water Feasibility Study (RWFS) Page 31 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx Section 4 Wastewater Characteristics and Facilities
4.1 Wastewater Facilities
The following sections provide details for the City’s existing wastewater collection and treatment facilities.
4.1.1 Wastewater Collection System
The City of Crescent City and the County Service Area (CSA), an agency of Del Norte County, each maintain a separate sanitary sewer collection system. The CSA maintains sewer collection facilities for the unincorporated areas outside the City limits. Flows generated within the CSA are collected and conveyed by the CSA’s collection system that includes 16 pump stations (Kennedy Jenks, 2021). The CSA’s collection system has an additional 5 pump stations at the City limits that transfer the collected CSA flows to the City’s collection system. The City system then conveys the combined City and CSA-generated flows to the Wastewater Treatment Facility (WWTF). The City is under contract with the CSA to provide operation and maintenance of CSA’s collection system, and treatment of CSA’s wastewater flows, but the City is not responsible for funding or implementing improvements to the CSA’s collection system.
The City and CSA collection system is comprised of over 17 miles of public sewer lines, 21 pump stations, and over 750 manholes (Kennedy Jenks, 2021). There are approximately 94,000 linear feet of sewer main and about 1,385 laterals within the City’s collection system (Kennedy Jenks, 2021). The City owns and operates 6 pump stations, with the remaining 15 pump stations owned and operated by the CSA. The City’s collection system was built in the 1950s and has had some updates since the original construction. Approximately half of the City’s collection system is constructed of vitrified clay and some sewer lines have been replaced with poly-vinyl chloride (PVC) pipe. Most service laterals on the new PVC lines have also been replaced with PVC. The City’s design flow for the sizing of new lines and to identify existing lines that need to be replaced is the 5-year recurrence interval storm (Facilities Plan, 2003).
The CSA maintains several permanent flow monitors to quantify the flow coming from the CSA into the City’s collection system. The CSA also maintains a rain gauge at Cooper Avenue and at the Elk Valley Pump Station and the City has a rain gauge at the WWTF. Operating status, runtime reports, and other data for all the City and CSA pump stations are tracked by the City on the Mission Communications online Platform.
4.1.1.1 Wet and Dry Weather Flows
The City’s coastal location makes it prone to intense rainfall and extremely wet rainy seasons.
Recycled water is typically used during the dry season, when rainfall is less frequent and less potable water is typically available. Table 4-1 below shows monthly average wet and dry weather flows for the WWTF. At the WWTF, dry weather flows are lower than wet weather flows and are a limiting factor for the volume of recycled water produced. It is expected that peak wet weather flow will increase in the future, augmenting water supply in the area (Kennedy Jenks, 2021).
Crescent City Recycled Water Feasibility Study (RWFS) Page 32 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx Table 4-1. Monthly Average Wet and Dry Weather WWTF Flows Month
Wet Weather Average Flow
(MGD)
Dry Weather Average Flow
(MGD)
January 3.9 -
February 4.4 -
March 3.2 -
April 3.8 -
May - 1.8
June - 1.3
July - 1.1
August - 1.1
September -- 1.1
October 1.1
November 1.4 -
December 2.1 -
Average 3.1 1.2
Source: WWTF flow data from April 2017 through February 2021.
4.1.2 Wastewater Treatment Facility
The Crescent City WWTF is located at 210 Battery Street, adjacent to the Crescent Harbor. The WWTF was originally constructed in the 1950s and has had several expansions since, with the most recent expansion of secondary treatment completed between 2008 and 2011. The WWTF serves a population of approximately 17,620 within Crescent City and the surrounding CSA.
The WWTF location can be seen on Figure 2-2. The plant has an average elevation of 15 feet above mean sea level (AMSL) and is protected from the open ocean by the Crescent Harbor breakwater. The WWTF secondary effluent is discharged to the Pacific Ocean via an outfall adjacent to Battery Point Lighthouse. The plant consists of primary, secondary, and tertiary treatment. Recycled water can be produced at the plant via ultraviolet (UV) light disinfection; however, the plant’s UV system is currently offline, and the plant historically has never produced recycled water. A process flow diagram of the WWTF is shown on Figure 4-1 and is further described in the following subsections.
4.1.2.1 Primary Treatment
The City wastewater collection system conveys the combined City and CSA wastewater flows to the WWTF headworks.
The headworks includes a mechanically cleaned screen, a flow-measuring Parshall flume, and a wet well in which five pumps are available to lift the flow to the primary clarifiers (NPDES, 2017). Primary treatment consists of two grit removal tanks followed by two rectangular primary clarifiers.
4.1.2.2 Secondary Treatment
Secondary treatment is provided by operation of the rotating biological contactors (RBC) and secondary clarifiers.
Crescent City Recycled Water Feasibility Study (RWFS) Page 33 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx The RBC system, installed in 1979, consists of three trains of four-stage RBCs with a combined surface area of 1.2 million square feet. The RBCs are rotated using 5- to 10-hp motors. Flow from the RBCs are directed to three rectangular secondary clarifiers. The minimum flow for maintaining biological treatment is approximately 0.30 MGD for one train, according to the treatment system operators and Appendix C. When an RBC train is shut down and restarted, it takes approximately one month of operation to reach efficient treatment. Typically, three RBCs are online at one time, however, if there is not enough flow, one of the RBCs will be shutdown.
In the summer months, when flow is reduced, the plant typically operates using two RBCs with the third on standby.
4.1.2.3 Tertiary Treatment
A membrane bioreactor (MBR) system was installed in 2008 to augment the secondary treatment capacity of the plant. The MBR can produce tertiary effluent and is currently used to improve effluent water quality to meet NPDES discharge limits. The MBR has three membrane units, two of which are typically used during operation, with the third membrane unit on standby.
A minimum flow of approximately 0.25 MGD is required to maintain efficient biological treatment, according to the treatment system operators. The MBR currently produces about
0.42 MGD when two membranes are operational. Due to age of the membranes, the transmembrane pressure of the system is high limiting the flow that can be treated through the MBR to the 0.42 MGD. The City is currently planning to replace all three membranes by October 2022. Which would allow an increase in the flow that can be treated through the MBR.
Permeate flows from the MBR are currently comingled with effluent from the secondary clarifiers and then disinfected in the chlorine contact basin using sodium hypochlorite. This blended effluent is dechlorinated using sodium bisulfite prior to discharge to the Pacific Ocean. Permeate flows from the MBR can be sent to the UV disinfection system as described in the following section.
4.1.2.4 Existing UV Disinfection System for Recycled Water In 2010, the City installed a UV disinfection system in the basement of the MBR building at the WWTF to produce tertiary-2.2 recycled water to be supplied for a future golf course and landscape irrigation system for a casino being developed by a local tribe, per conversations with City and plant staff. The UV disinfection system was sized for 2.0 MGD and included two 25-hp
0.60 MGD pumps, a flow meter, two UV reactors, and recycled water distribution piping. The two existing pumps would convey tertiary water from the MBR filtrate tank through the UV disinfection system. A 12-inch recycled water distribution main exits the MBR basement through the east wall underground and proceeds southeast of the MBR building outside of the WWTF fence with the intent of delivering recycled water to the customer connection. However, the local tribe’s irrigation project was not completed, so the 12-inch recycled water distribution main was capped near the WWTF access gate on Howe Drive, and the UV disinfection system was left offline. Based on conversations with City staff, the City did not submit a formalized Title 22 Engineering Report and Notice of Intent for recycled water reuse to the California Regional Board and Division of Drinking Water.
A few years after the installation of UV disinfection system and 12-inch recycled water pipeline and cap, a recirculation loop was built to return tertiary produced water back to the treatment plant for cleaning and testing purposes of the UV disinfection system based on conversations Crescent City Recycled Water Feasibility Study (RWFS) Page 34 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx with City Staff. A recirculation pipe was tied into the existing 12-inch recycled water cap and was installed underneath the plant fence and penetrated above ground in the grass area between the plant fence and MBRs near the Howe Gate access drive. The pipeline then continues toward the secondary clarifiers parallel to the access drive, going underneath the existing MBR access stairs, and discharges into the one of the secondary clarifiers, as shown in the photos on Figure 4-3. The City has since not identified any recycled water customers but could produce recycled water if customers are identified.
4.1.2.5 Solids Handling
Solids handling consists of gravity thickening primary sludge, rotary drum thickening of secondary sludge, and anaerobic digestion of thickened solids. Both digesters are heated and mixed. Digested solids are dewatered using a belt filter press and hauled to a landfill.
4.1.2.6 Discharge
Effluent from the WWTF is discharged to the Pacific Ocean by gravity via a new 24-inch diameter outfall installed in 2006. The plant has an existing 12-inch diameter outfall installed in the 1950s when the plant was first constructed that can be used to convey storm flows by using the existing effluent storm pumps. Both outfalls join in a manifold before discharging into a rocky slot in the surf zone adjacent to Battery Point Lighthouse. The new 24-inch outfall has an effluent conveyance capacity of 12 MGD, and the existing 12-inch outfall has a capacity of 2 MGD for gravity discharge or 8 MGD if the effluent pumps are used. Since installation of the new 24-inch outfall, no pumping has been needed to discharge effluent during the wet weather season and the older,12-inch outfall has remained as a backup. 2!! 2!!
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Scale: Feet
City of Crescent City
Crescent City, CA
Crescent City Wastewater System
K/J 2076056*00
August 2022
Figure 3-1
Z:\Projects\CityOfCrescentCity\Events\20211013_RWFS\Fig4-1_City&CSAFacilities.mxd Date: 8/9/2022 Printed by: MaryEllenMcCarty Legend
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City of Crescent City Boundary
Sewer Lines
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Source: Esri, Maxar, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community Outfall
Note: The northernmost pump
station location is approximate.
Figure 4-1
Order No. R1-2017-0002
City of Crescent City
NPDES No. CA0022756
Attachment C – Wastewater Flow Schematic C-1
C.
ATTACHMENT C – FLOW SCHEMATIC
Figure 4
WWTF Process
Flow Diagram Figure 4-2
K/J 2076056*00
September 2022
WWTF Recirculation
Pipe Photos
Figure 4-3
K/J 2076056*00
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4.2 Wastewater Facility Operations and Maintenance
The WWTF staff performs a variety of scheduled, preventive, predictive, and breakdown maintenance on their equipment to ensure equipment availability to meet plant process operation requirements. The City uses a Computerized Maintenance Management System (CMMS) system to track and schedule these maintenance activities (SSMP, 2018). The operations of the WWTF are contracted out to a third-party engineering firm.
As described in the City’s Sanitary Sewer Management Plan, every-other-year maintenance is performed on the gravity sewer mains by the City of Crescent City Public Works Department (SSMP, 2018). Each year, specific sewer lines are identified for routine cleaning and all sewer mains are cleaned at least once during any given two-year period. Problematic sewer mains are identified, prioritized, and cleaned more frequently based on review of maintenance history and sewer system characteristics. Maintenance activities include high velocity cleaning, visual inspections, and preventive repairs. In addition to preventive maintenance, the City implements a proactive maintenance program where “non-problem” sewers are also scheduled for maintenance and cleaning but on a less frequent basis, at least once every five years. If a Sanitary Sewer Overflow (SSO) occurs, it is inspected within 24-hours and closed-circuit television (CCTV) may be used to identify any necessary repairs or special maintenance needs (SSMP, 2018). A system-wide manhole inspection program has been developed by the City and is performed at least once every two years.
The City also has a routine preventive operation and maintenance program for its pump stations and, in general, each pump station is visually inspected weekly. The City and CSA co-own a CCTV system purchased in 2017. Since a considerable portion of the I&I comes from the CSA, inspections of the CSA collection system were prioritized to identify the most critical rehabilitation and replacement areas. Sewers that are identified as needing urgent repair are replaced within one year. Those that are identified as needing structural improvement within five years are scheduled for replacement or rehabilitation as appropriate funds become available and are inspected annually until fixed (SSMP, 2018).
All the six pump stations within the City service area have an emergency alarm system for monitoring power failure, high wet well, and dry well conditions. The City has a routine operation and maintenance program for these pump stations. Generally, each pump station is inspected visually each week (SSMP, 2018).
WWTF maintenance consists of draining and cleaning RBC trains, replacing equipment parts as needed such as valves, anoxic mixers, pumps, and treatment media per conversations with treatment plant operators.
4.3 Water Quality of Effluent
The WWTF is operated in compliance with NPDES permit requirements. The NPDES permit establishes limitations for the WWTF and prohibits, among other restrictions, discharges of untreated or partially treated waste, sanitary sewer overflows, and by-pass of untreated waste containing concentrations of pollutants more than those outlined in the permit. The discharge of secondary treated wastewater must maintain compliance with effluent limitations set by the permit. The Crescent City WWTF is currently permitted under NPDES Order No R1-2017-0002, Crescent City Recycled Water Feasibility Study (RWFS) Page 39 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx which expired on March 31, 2022. The City submitted an NPDES permit application for the renewal and is in the process of obtaining an updated permit.
The most recent reporting year data available on the California Integrated Water Quality System Project (CIWQS) for Crescent City’s WWTF is 2020. Table 4-2 provides a summary of the WWTF’s 2020 12-month averages for effluent water quality parameters.
Table 4-2. 2020 12-Month Averages of Crescent City WWTF Effluent Water Quality Monitoring Point at WWTF Parameter Concentration Result EFF-001 Total Ammonia Nitrogen
(mg/L)
8.22 EFF-001 Biochemical Oxygen Demand
(BOD) (5-day @ 20 Deg. C)
(lb/day)
140
EFF-001 Total Chlorine Residual (mg/L) 0.08
EFF-001 Fecal Coliform (MPN/100 mL) 6.6
EFF-001 Total Suspended Solids (TSS)
(lb/L)
85 EFF-001 Turbidity (NTU) 5.4
EFF-001 pH (SU) 7.33
Source:
https://ciwqs.waterboards.ca.gov/ciwqs/readOnly/PublicReportEsmrAtGlanceServlet?reportID=2&isDrilldown=true&d ocumentID=1932447
4.4 Existing Wastewater Flows
4.4.1 Seasonal Flow Variation
The Crescent City’s WWTF exhibits typical seasonal variations in influent flow due to the collection system capturing both sewer and storm drainage flows. Wastewater flows are largely influenced by heavy rainfall during the early and late months of the year as shown in Appendix C. Based on data from April 2017 through February 2021, average influent flows ranged from
1.0 MGD to 3.0 MGD, with a peak influent flow of 7.92 MGD (February 2019). The average effluent flows during this period ranged from 0.75 MGD to 2.75 MGD, with a peak effluent flow of 5.27 MGD (February 2021) and a minimum effluent flow of 0.61 MGD (October and November 2021). The Facility design flow is 1.86 MGD (the average dry weather treatment capacity) and the peak wet weather treatment capacity is 6.12 MGD (NPDES, 2017). Based on a 2019 assessment, the hydraulic capacity of the treatment system is limited by the hydraulic capacity of the chlorine contact tank, approximately 6.1 MGD (Kennedy Jenks, 2021).
4.4.2 WWTF Influent Flow Split
As described previously in Section 4.1.2, both RBC and MBR systems are used to treat the wastewater influent and produce secondary effluent that meet NPDES discharge requirements.
To enhance water quality and meet limitations outlined in the NPDES Permit, the influent plant Crescent City Recycled Water Feasibility Study (RWFS) Page 40 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx flow splits after primary treatment to the RBC and MBR treatment systems. The flow split between the RBC and MBR is driven by the following two factors:
1. Minimum flow needed for effective biological treatment of the RBC and MBR treatment systems
2. Flows produced from each treatment system needed to blend before discharge to meet NPDES requirements.
4.4.2.1 Current Flow Split
Per conversation with plant operations staff, a flow range of 0.30 to 0.40 MGD from the MBR is needed to blend with RBC effluent before discharge to meet NPDES requirements. For dry weather flows of 1 MGD, the flow split is usually 70% through the RBC and 30% through the MBR. For dry weather flows less than 1 MGD, the flow split is usually 60% through the RBC and 40% through the MBR, as shown in Table 4-3. These flow splits are managed by the WWTF operators to ensure effluent complies with the NPDES permit limitations.
Table 4-3. Estimated Influent Flow Split
Dry Weather < 1 MGD Dry Weather = 1 MGD
% MGD % MGD
% of Influent Sent
to MBR
40% <0.4 30% >0.3
% of Influent Sent
to RBC
60% <0.6 70% >0.7
Source: Discussions with City WWTF Operators.
4.4.2.2 Future Flow Split Post Membrane Replacement
After the MBR membranes are replaced, the transmembrane pressure should be reduced allowing for more flow to be treated through the MBR. Per conversation with plant operations staff, the anticipated flow split to the MBRs and RBCs would be 70% and 30%, respectively, assuming an average dry weather influent flow of 1.2 MGD.
4.5 Commercial and Industrial Treatment Facilities
There are three industrial water and wastewater customers within the Crescent City limits.
These facilities are not City owned but discharge their industrial process water to the City’s sewer system under a pretreatment discharge permit. These facilities include Rumiano Cheese Company, Seaquake Brewery, and Port O’Pints Brewery.
4.5.1 Rumiano Cheese Company
Rumiano Cheese Company (Rumiano) is located at 511 9th Street and was founded in 1919.
Rumiano processes approximately 45,000 gallons of dairy products per day, five days a week.
Waste produced from dairy production is managed and treated within the Rumiano site. Sludge is stored in silos on-site while liquid wastewater streams are treated by two separate pre- Crescent City Recycled Water Feasibility Study (RWFS) Page 41 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx treatment systems. The two pre-treatment processes for liquid process water are a moving bed biofilm reactor and dissolved air flotation (MBBR/DAF) treatment system and an ultraviolet and reverse osmosis (UV/RO) treatment system. Each of these systems treat two separate liquid industrial process streams within Rumiano and are described in further detail in the following sections. Effluent from the UV/RO system is stored in the Polished Water Silo (see Figure 4-5) and could potentially be a source of recycled water prior to discharge to the City sewer system.
Effluent from the UV/RO system that is produced in excess of the silo storage capacity, or not used, is comingled with the effluent from the MBBR/DAF system and discharged to the City’s WWTF under a pretreatment permit. The process flows are generated from the production lines and are separate from the facility sanitary sewer flows. Conversations with Rumiano staff have also indicated that effluent production may increase in the future due to plans to expand treatment facilities.
4.5.1.1 Rumiano MBBR/DAF Pre-Treatment System
The MBBR/DAF treatment system was installed in 2004 and has a treatment capacity of 60,000 gpd. The MBBR/DAF system treats plant drainage from lactose, whey, cheese, and cleaning generated in Rumiano. The drainage wastes are collected and routed to a collection pit and flow to the MBBR/DAF system. Figure 4-4 below portrays Rumiano’s MBBR/DAF pre-treatment system. The pre-treatment process for this waste stream is outlined in the following steps:
1) The waste flows through rotary solids screening and solids fines are discarded in the dumpster while liquid organic food is hauled to a manure pond. 2) Wastewater then goes to two (2) 30,000-gallon equalization tanks. 3) Wastewater is then treated by three (3) moving bed biofilm reactors (MBBR) with bacteriological media pellets.
4) Wastewater is then conveyed through the DAF unit where generally regarded as safe (GRAS) polymer is added to the system as needed.
5) All treated wastewater effluent is conveyed to the Crescent City WWTF if the pH is between 6-9 and the Total Suspended Solids (TSS) is below 140 parts per million (ppm).
TSS and pH levels are recorded twenty-four seven on chart recorders. The WWTF also takes samples of the effluent to confirm it meets water quality effluent requirements. If the wastewater does not meet these parameters, the wastewater is pumped through the pre-treatment system again.
Further water quality characterization of the MBBR/DAF effluent would need to occur to evaluate the feasibility of using the effluent as recycled water. From the given data, it is not clear if the DAF effluent water quality will meet quality requirements to be permitted. There are occasional BOD/TSS concentrations greater than 30 mg/L, as well as potential odor concerns.
For the purposes of this report, the effluent from this system is not considered for use as a recycled water. Further analyses and a more thorough wastewater characterization for the MBBR/DAF effluent in the future could allow for use as recycled water.
Crescent City Recycled Water Feasibility Study (RWFS) Page 42 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx Figure 4-4. Rumiano Cheese Company Pretreatment System
Figure 4
Rumiano Cheese
Company Site Plan
Figure 4-5
K/J 2076056*00
August 2022
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4.5.1.2 Rumiano UV/RO Pre-Treatment System
The other on-site pre-treatment system at Rumiano consists of ultra-violet and reverse osmosis treatment. The effluent from this treatment system is stored in a 30,000 gallon Polished Water Silo and used for a clean in place (CIP) system and on-site tank cleaning. Rumiano is considering using the treated effluent to supplement process water used for the cooling towers.
This process treatment system treats the sweet whey wastewater stream, which is a separate process stream from the MBBR/DAF system. This system produces approximately 30,000-gallons a day of polished effluent and is stored in the 30,000-gallon Polished Water Silo in the treatment facility, as shown on Figure 4-5.
Currently, Rumiano only uses 18,000 gallons a day from the Polished Water Silo for cleaning purposes. The remaining 12,000 gallons are comingled with MBBR/DAF effluent and discharged to the City’s WWTF as indicated on Figure 4-4 above. Based on discussions with Rumiano for the purposes of this feasibility study, the excess 12,000 gallons a day of treated and disinfected effluent could potentially be used as a recycled water source for nearby irrigation users, prior to comingling with the MBBR/DAF effluent and being discharged to the City’s WWTF. This option is explored further in Section 6, Section 7, and Section 8.
4.5.1.3 Rumiano’s Effluent Water Quality
Rumiano discharges approximately 20,000 gpd to 75,000 gpd with an average of 43,500 gpd to the City’s WWTF. Rumiano’s discharge effluent includes both the MBBR/DAF effluent and the excess 12,000 gallons from the UV/RO treatment system effluent. Discharge parameters measured are TSS, BOD, and pH. A summary of the monthly effluent flows and water quality parameters are summarized in Table 4-4. Water quality of just the UV/RO effluent stored in the silo may be cleaner, however, water quality information has not been provided at this time to confirm. Pathogens, such as total coliform bacteria, are not commonly required to be monitored by industrial producers as industrial effluents are separate from sewer effluents. To determine the feasibility of using Rumiano’s effluent for recycled water production, further water quality analyses might be required.
Crescent City Recycled Water Feasibility Study (RWFS) Page 45 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx Table 4-4. Rumiano Cheese Company 2021 Monthly Effluent Flows and Water Quality Data
Month
TSS
(mg/L)
BOD
(mg/L) pH
Average
Effluent
(gpd)
Minimum
Effluent
(gpd)
Maximum
Effluent
(gpd)
Jan 25.7 4.85 8.1 39,942 9,747 70,423
Feb 10.7 26.7 8.2 39,739 9,747 70,423
Mar 8 8.3 8.3 42,745 12,700 66,170
Apr 14.1 7.2 8.2 48,276 19,224 60,913
May 12.3 6.9 8.2 48,930 22,579 67,232
Jun 80.4 39.6 8.1 45,352 16,708 63,660
Jul 11.4 7 8.1 45,672 20,920 64,608
Aug 19.3 7.5 8.1 41,768 20,061 58,445
Sep 31.8 9.2 8.1 44,896 15,891 73,498
Oct 19.5 9.1 8.1 44,896 15,891 73,498
Nov 20.4 9.5 8 40,983 12,202 68,228
Dec 5.6 10.7 8.2 40,379 10,332 70,680
Average 17.8 9.9 8.1 43,486 14,361 66,147
Source: Rumiano Cheese Company (March 2022)
4.5.2 Seaquake Brewery
Seaquake Brewery is located at 400 Front Street. Seaquake Brewery does not pretreat their industrial process water prior to discharge to the City sewer system. They have an average summer effluent flow of 1,500 gpd. Their 2021 effluent water quality average is summarized as follows:
• TSS = 3,174 mg/L
• BOD = 14,000 mg/L
• pH = 6
Per water meter data, the brewery’s 2018 average water use reported was an annual usage of
2.0 AFY with an average monthly use of 1,600 gpd. Due to the low volume of effluent produced, the high TSS and BOD effluent concentrations, and the low non-potable water demand, Seaquake Brewery is not a candidate for production or utilization of recycled water.
4.5.3 Port O’Pints Brewery
Port O’Pints Brewery is located at 1215 Northcrest Drive. Port O’Pints does not pretreat their industrial process water. They have an effluent average of 200 gpd and discharge only a couple Crescent City Recycled Water Feasibility Study (RWFS) Page 46 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx times a week to the City sewer system. Their 2021 effluent water quality average is summarized as follows:
• TSS = 162 mg/L
• BOD = 13,500 mg/L
• pH = 7
The brewery’s 2018 average water use reported per their meter data was an annual usage of
0.9 AFY and an average monthly use of 700 gpd. Due to the low volume of effluent produced, the high BOD effluent concentrations, and the low non-potable water demand, Port O’Pints Brewery is not a candidate for production or utilization of recycled water.
Crescent City Recycled Water Feasibility Study (RWFS) Page 47 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx Section 5 Treatment Requirements
This section discusses regulations and treatment requirements for recycled water use to protect public health, including the most recent regulatory landscape for potable reuse. Supporting information is provided in Appendix B which is a matrix of Recycled Water Uses Allowed in California.
5.1 Multi-Barrier Approach
Recycled water begins as wastewater and undergoes a series of treatment steps, using a multibarrier approach, to remove organic matter and pollutants. As a result of the drought and climate-related water supply limitations in much of California, recycled water for potable reuse has been implemented in more water scarce areas of the state. The production and use of recycled water must adhere to strict regulations stipulating the levels of treatment, allowable types of reuse and water quality requirements. Figure 5-1 below illustrates the multi-barrier approach to reuse whether it is for non-potable or potable uses, highlighting the increasing level of treatment necessary to produce the right quality of water for the right use.
Crescent City Recycled Water Feasibility Study (RWFS) Page 48 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx Figure 5-1. Multi-Barrier Approach to Reuse
This RWFS focuses on non-potable reuse, as defined below:
• Non-potable reuse refers to the use of tertiary treated municipal wastewater for a specific purpose other than drinking such as landscape irrigation, industrial uses, and agriculture or for environmental benefits. Non-potable reuse usually requires an independent “purple pipe” distribution system for conveying recycled water to customers separate from the potable supply. In California, non-potable reuse is ongoing throughout the state for the last century and regulations for non-potable reuse have been in place since the 1970s. • Potable reuse refers to the intended use of advanced treated municipal wastewater to augment a water supply that is used for drinking and all other potable or non-potable purposes. Unplanned potable reuse, where one community draws raw water supplies downstream from discharges from wastewater treatment plants, is regulated by federal discharge requirements. Planned potable reuse involves a more formal public process and regulatory consultation program to implement and the regulations in California for the indirect and direct use of recycled water are at varying stages of development.
Crescent City Recycled Water Feasibility Study (RWFS) Page 49 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx • Indirect potable reuse (IPR) is the purposeful introduction of tertiary treated recycled water or advanced treated recycled water into an untreated drinking water supply source, such as groundwater in an aquifer or surface water in a large reservoir. The recycled water may require blending with a diluent water, at a specified blending ratio for groundwater replenishment, and advanced treated water must be added to a specified volume of surface water during reservoir augmentation. Travel time between the point of addition and eventual extraction for treatment at a drinking water treatment plant is clearly specified. In addition, reservoir augmentation requires retreatment at a drinking water treatment plant.
Regulations for groundwater replenishment using recycled water became effective on June 18, 2014. Surface water augmentation regulations were adopted on March 06, 2018. • Direct potable reuse (DPR) is the purposeful introduction of advanced treated recycled water into a drinking water supply immediately upstream of a drinking water treatment plant or directly into the potable water supply distribution system downstream of a water treatment plant. Currently, DPR is not yet included as an allowable use in California; however, the State Water Resources Control Board (SWRCB) – Division of Drinking Water (DDW) released a proposed Framework for regulating DPR in August 2019, to establish the framework for regulating potable reuse projects and the requirements for developing uniform water recycled criteria for DPR. Preliminary findings and recommendations have been drafted by an Expert Panel to establish draft DPR criteria. Regulations for DPR are expected by end of 2022.
Meeting regulatory requirements is an integral part of implementing any non-potable or potable recycled water project. The following sections summarize the regulatory requirements and administrative responsibilities, with an emphasis on regulations relating distribution and use of recycled water in California. A discussion of the most recent regulatory landscape for potable reuse is also provided.
5.2 Overview of Regulatory Requirements
The production, discharge, distribution, and use of recycled water are subject to federal, state, and local regulations, the primary objectives of which are to protect public health.
Federal requirements relevant to the discharge of recycled water, or wastewater, and any other liquid wastes to “navigable waters” are contained in the federal Clean Water Act (CWA).
The CWA established the National Pollutant Discharge Elimination System (NPDES), a permit system for discharge of contaminants to navigable waters. NPDES requires that all municipal and industrial dischargers of liquid wastes apply for and obtain a permit prior to initiating discharge. There are no federal regulations governing water reuse in the United States, thus regulations (or guidelines) for recycled water are developed and implemented at the state government level.
In the State of California, recycled water requirements are administered by DDW, formerly under California Department of Public Health (CDPH), and individual Regional Water Quality Crescent City Recycled Water Feasibility Study (RWFS) Page 50 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx Control Boards (RWQCBs). The regulatory requirements for recycled water projects in California are contained in the California Code of Regulations (CCR) -Title 22 and Title 173:
• Title 22 stipulates the levels of treatment for different uses of recycled water, permissible types of reuse, and minimum recycled water quality requirements. In 2014 Title 22 was revised to include regulations for a Groundwater Replenishment Reuse Project (GRRP).
Water meeting standards for non-potable reuse is considered safe for non-drinking purposes while compliance with GRRP requirements renders water safe for drinking purposes. Routine monitoring is required to ensure that the intended quality is consistently being produced.
• Title 17 focuses on the protection of drinking (potable) water supplies through control of cross-connections4 with potential contaminants, including non-potable water supplies such as recycled water. Title 17, Group 4, Article 2 – Protection of Water System, Table 1, specifies the minimum backflow protection required on the potable water system for situations in which there is potential for contamination to the potable water supply.
Local requirements vary by county and city and typically provide additional guidance to meet local health agency or public water supplier guidelines and permit/code requirements.
5.2.1 State Recycled Water Policy
In 2009, the SWRCB adopted a Recycled Water Policy (RW Policy) to establish more uniform requirements for water recycling throughout the State and to streamline the permit application process in most instances. The RW Policy includes a mandate that the State increase the use of recycled water over 2002 levels by at least 200,000 AFY by 2030. Also included are goals for stormwater reuse, conservation, and potable water offsets by recycled water. The onus for achieving these mandates and goals is placed both on recycled water purveyors and potential users.
The RW Policy requires that salt and nutrient management plans (SNMP) be developed for every groundwater basin in California and adopted as Basin Plan Amendments by 2015. These management plans are to be developed by local stakeholders and funded by the regulated community and are intended to coordinate salinity management regionally. An alternative approach to compliance with SNMP may be to conduct an anti-degradation analysis for the use of recycled water at agronomic rates to demonstrate that the recycled water will not result in negative water quality impacts. This approach should be vetted with the Regional Board staff as the project proceeds to implementation.
3 State requirements for production, discharge, distribution, and use of recycled water are contained in the California Water Code, Division 7-Water Quality, Sections 1300 through 13999.16 (Water Code); the California Administrative Code, Title 22-Social Security, Division 4 Environmental Health, Chapter 3-Reclamation Criteria, Sections 60301 through 60475 (Title 22); and the California Administrative Code, Title 17-Public Health, Chapter 5, Subchapter 1, Group 4-Drinking Water Supplies, Sections 7583 through 7630 (Title 17). 4 A cross-connection is an unprotected actual or potential connection between a potable water system used to supply water for drinking purposes and any source or system containing unapproved water or a substance that is not or cannot be approved as safe, wholesome, and potable, which in this case will be recycled water. By-pass arrangements, jumper connections, removable sections, swivel or changeover devices, or other devices through which backflow could occur, shall be considered to be cross-connections Crescent City Recycled Water Feasibility Study (RWFS) Page 51 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx The RW Policy also required the formation of a Blue-Ribbon Advisory Panel (Panel) to guide future actions with respect to contaminants of emerging concern (CECs). CECs include chemicals and other substances that have no regulatory standard, have recently been “discovered” in natural streams, and potentially cause deleterious effects in aquatic life at environmentally relevant concentrations. The Panel was convened in May 2009 and completed in May 2010. A final report was issued in June 2010. The recommendations of the Panel resulted in the finalization of the Groundwater Recharge and Reuse Regulations in June 2014, which incorporated the Panel’s recommendations.
The RW Policy was revised in 20135 to include monitoring requirements for CECs based on the recommendations from the Panel. In fall of 2016, the SWRCB started the process of revising the RW Policy to reaffirm support for the development of salt and nutrient management plans, reconvene the Science Advisory Panel on CECs in recycled water6, and direct staff to initiate a stakeholder process to update the recycled water policy. Once started, this process is expected to take between twelve and eighteen months.
Most recently, the SWRCB adopted an amendment to the RW Policy, effective April 8, 2019, to address future actions related to monitoring CECs in recycled water. The purpose of the 2019 amended Recycled Water Policy is to provide direction to RWQCBs regarding the criteria to be used when issuing permits for recycled water projects.
5.2.2 Statewide General Order
On June 7, 2016, the SWRCB adopted Water Reclamation Requirements for Recycled Water Use7 (General Order). Similar to the RW Policy, the intent of the General Order is to streamline the permitting of recycled water use statewide and encourage the use of recycled water as a valuable resource. The General Order is used to permit non-potable recycled water distribution and use. The production of recycled water at a wastewater treatment facility is permitted under a RWQCB permit based on the General Order requirements.
5.3 Non-Potable Reuse Requirements
The forms of non-potable reuse that are permitted in California vary based on (1) the degree of treatment required and (2) the intended use of the recycled water, based on CCR Title 22. As a general rule, when more treatment is provided, the final use of the water is less restricted. The levels of treatment, from the lowest level (with the highest restrictions) to the highest level (with the lowest restrictions), per the regulatory classifications (CCR Title 22) are:
• Undisinfected secondary recycled water
• Disinfected secondary – 23 recycled water
• Disinfected secondary – 2.2 recycled water
• Disinfected tertiary recycled water
5 http://www.swrcb.ca.gov/water_issues/programs/water_recycling_policy/docs/rwp_revtoc.pdf 6 https://www.waterboards.ca.gov/water_issues/programs/water_recycling_policy/recycledwater_cec.shtml 7 http://www.waterboards.ca.gov/board_decisions/adopted_orders/water_quality/2016/wqo2016_0068_ddw.pdf Crescent City Recycled Water Feasibility Study (RWFS) Page 52 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx Disinfected secondary -23 recycled water and disinfected secondary – 2.2 Recycled Water differ in the degree of disinfection required to achieve different total coliform bacteria concentrations after disinfection. Appendix B includes a summary table of allowable uses of recycled water in California and the associated treatment level.
5.3.1 Non-Potable Treatment Processes
Wastewater from a sanitary sewer undergoes primary and secondary treatment. Primary treatment removes large solids, scum and debris, and heavier sludge that settle out in primary holding tanks. Secondary treatment utilizes micro-organisms to break down and consume organic matter. Together these processes produce secondary effluent to meet land discharge or discharge (NPDES) requirements to a waterway, bay or the ocean.
Additional treatment is typically required to produce recycled water for non-potable reuse.
Tertiary treatment provides filtration to remove suspended solids and other pollutants through the use of sand or media filtration or membrane filters. Disinfection serves to destroy bacteria and viruses through the addition of chemicals (such as chlorine) or ultraviolet (UV) light.
Disinfection may follow secondary or tertiary treatment, depending on the intended reuse type.
Figure 5-2 provides a summary of the non-potable reuse options, the associated treatment required, and the allowable uses for each type of non-potable reuse. Additional detail about treatment criteria for each type of use is provided in Appendix B. The treatment processes assumed for implementation of non-potable reuse in the City will be described as part of the project alternatives description in Section 8.
Crescent City Recycled Water Feasibility Study (RWFS) Page 53 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx Figure 5-2. Types of Non-Potable Reuse and Associated Treatment Processes
5.3.2 Customer Based Water Quality Objectives
Recycled water quality requirements for a specific use may also have to adhere to customerbased water quality standards that go beyond the minimum regulatory requirements. For example, though removal of total dissolved solids (TDS, a measure of salinity) is not required for recycled water by regulations, it may be desirable depending on the end use and the concentration of TDS in the source water.
5.3.2.1 Irrigation Requirements
Table 5-1 provides a summary of broadly accepted general water quality guidelines available for use of recycled water for landscape and agricultural irrigation. These guidelines are not plant specific and therefore may be too restrictive for some plants and not restrictive enough for more sensitive plants. However, these guidelines are considered to be conservative (Tchobanoglous et al. 2004; Ayers and Westcot 1985; Tanji et al. 2007).
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Constituent
or
Parameter
Issue of
Concern Units None
Slight to
Moderate Severe
Boron Toxicity to
Plants
mg/L < 0.7 0.7 to 3.0 > 3.0
Chloride Ion toxicity,
Spray
(Overhead)
Irrigation
mg/L < 100 >100
Surface
irrigation
mg/L < 140 140 to 350 > 350
pH Misc. Effects -- Normal
Range 6.5 to
8.4 Residual
chlorine
Leaf Burn
from Spray
(Overhead)
Irrigation
mg/L < 1 1 to 5 > 5
Salinity as
TDS
Plant
Response
mg/L < 450 450 to 2,000 >2,000
Notes: TDS = total dissolved solids; N/A = not available Source: Water quality objectives from 2004 Wastewater Engineering: Treatment and Reuse (Tchobanoglous et al.), based on Ayers and Westcot (1985) with additional information from Tanji et al. (2007). (a) None – Suitable water quality as is; Slight to Moderate – Manageable with proper irrigation scheduling, amendments, and/or plant selection; Severe – Problematic, may need partial removal of the constituent.
5.3.2.2 Commercial/Industrial
Non-irrigation uses, such as toilet and urinal flushing and cooling towers that are dual-plumbed with an internal purple pipe system to separate potable water from recycled water (non-potable) may have water quality objectives beyond meeting Title 22 objectives. For aesthetic reasons, it is preferable that recycled water used for toilet and urinal flushing is odorless and colorless. This is generally recommended by professionals in the water reuse industry.
Organic and inorganic compounds in recycled water can cause discoloration and odor.
Oxidizing agents such as chlorine, ozone, and hydrogen peroxide can be used for removal of color and odor, and UV light may also contribute to the removal of color. Hydrogen peroxide (H2O2) is an oxidant commonly used in water treatment and wastewater reclamation for eliminating color and odor; it is less effective than ozone but easier to implement. Chlorine is less effective for odor and color removal compared to ozone and hydrogen peroxide and so is not specifically used for this purpose.
Cooling towers prefer receiving a water source with a consistent water quality to achieve specific water quality requirements that align with operational and maintenance practices.
Variable water quality can be a challenge as it impacts the number of cycles and chemical requirements; additionally, ammonia concentration is of greatest concern due to the potential for corrosion. Removal of salinity and ammonia may be desirable to meet cooling tower water Crescent City Recycled Water Feasibility Study (RWFS) Page 55 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx quality objectives. It is not uncommon for cooling towers to have small package Reverse Osmosis (RO) plants to manage water quality from potable water sources. Thus, if cooling towers are selected as a future customer it would be important to work closely with their operators to understand the elements of the specific cooling system and their current practices and needs.
5.4 Potable Reuse Treatment Requirements
Potable reuse was first explored in California by the Los Angeles County Sanitation District. The Montebello Forebay Project started surface spreading of recycled water for groundwater replenishment in 1962, at a time when there were no regulations governing groundwater replenishment. The first draft groundwater replenishment regulations were published over a decade later in 1976, and soon after the Water Factory 21 at Orange County Water District became the first subsurface injection groundwater replenishment project. These two pioneering projects were instrumental in helping regulators understand the risks and control tools needed for reliable, safe potable reuse. These projects played a large role in guiding the final groundwater replenishment regulations, which were published in June 2014. Groundwater replenishment is the only form of potable reuse currently in practice in California, with seven projects providing approximately 200,000 AFY of potable reuse water.
Legislative action, namely California Senate Bill 918 (SB 918), mandated that the groundwater replenishment regulations be finalized by December 2013 and also set out two additional potable reuse goals: (1) to develop uniform criteria for surface water augmentation (SWA) by December 2016, and (2) to assess the feasibility of developing future regulations for DPR by December 2016. DDW released the DPR feasibility analysis at the end of 2016, which concluded that it is feasible to develop and adopt regulations for using recycled water as drinking water, provided that certain research and key knowledge gaps are addressed. Draft SWA regulations were released in September 2017 and the final SWA regulations were adopted by the DDW on March 6, 2018. The content and requirements of these three forms of potable reuse—groundwater replenishment reuse, surface water augmentation, and direct potable reuse—are discussed in the following sections.
5.4.1 Potable Treatment Processes
For indirect and direct potable reuse, additional treatment processes are added beyond secondary treatment to remove dissolved solids and other contaminants. An advanced water treatment facility (AWTF) or advanced water purification facility (AWPF) provides additional steps to purify recycled water. The specific combination of treatment processes needed for a given project will depend on the quality of the treated wastewater and the intended use.
Typically, an AWTF would begin with microfiltration/ultrafiltration (MF/UF) as pretreatment prior to an advanced filtration process, such as a high-pressure, semi-permeable reverse osmosis RO membrane, that allows water to pass through while rejecting most other contaminants. The next step would employ an advanced oxidation process (AOP), which typically combines UV treatment with the addition of hydrogen peroxide (UV/H2O2), ozone/H2O2, UV/Cl2, or UV/ozone to degrade most natural and synthetic organic compounds. Other treatment processes which could serve as an additional pathogen barrier may include ozone, Crescent City Recycled Water Feasibility Study (RWFS) Page 56 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx and/or Biologically Activated Carbon (BAC). Section 3.6 provides a description of these treatment processes, the treatment benefits and removal credits associated with each.
For indirect potable reuse, an environmental buffer, such as a groundwater aquifer or a surface water reservoir, serves as an additional barrier. A drinking water treatment facility may offer another barrier before the advanced treated water is delivered for potable use.
The range of treatment train configuration options for potable reuse is shown in Figure 5-3 below. One way to differentiate the various forms is based on the degree of separation—both in time and space—between the treatment of water and its ultimate consumption by the public.
Viewed through this lens, the different forms of potable reuse lie along a spectrum of varying degrees of “directness.”
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5.4.2 Groundwater Recharge Reuse Treatment Requirements Groundwater replenishment requirements (GRR) are described in terms of (1) surface spreading and (2) subsurface/direct injection (herein referred to as direct injection). Both of these GRR options are governed by the GRR Regulations, which were promulgated on June 18, 2014. The City has determined that space limitations and hydrogeologic conditions constrain any GRR project to direct injection. Hence, the focus of this section is on regulations related to direct injection projects. Table 5-2 summarizes the GRR Regulations for direct injection.
In direct injection, recycled water that has gone through a full advanced treatment (FAT) process (i.e. MF, RO and an AOP) at an AWTF, is directly injected into the groundwater zone.
Key aspects of the GRR treatment requirements are summarized in Table 5-2.The SWRCB allocates treatment credits, calculated as log reduction values (LRV), on a case-by-case basis for each project. Factors that may influence the LRV that is credited for a given unit process include the type of monitoring provided and the performance of the unit process. The implementation of FAT allows for the use of up to 100% recycled water (e.g. no dilution requirement) and as little as a 2-month minimum retention time, if the 12/10/10 microbial logremoval for virus, Giardia, or Cryptosporidium (V/G/C) requirements is met.
Table 5-2. Summary of GRR Regulations for Direct Injection Water Quality Limits for Recycled
Water
Treatment and Diluent Requirements
≥ 12-log virus reduction
≥ 10-log Giardia cyst reduction
≥ 10-log Cryptosporidium oocyst
reduction
Drinking water MCLs (except for nitrogen)
≤ 10 mg/L total nitrogen
Action levels for lead and copper
TOC ≤ 0.5/RWC
Injection with FAT (i.e., subsurface
application)
Oxidation, Reverse Osmosis (RO),
Advanced Oxidation Process (AOP) and
up to up to 100% RWC with FAT.
Notes: MCL = maximum contaminant level, TOC = Total Organic Carbon RWC = recycled water contribution (the quantity of recycled water applied at the recharge site divided by the sum of the quantity of recycled water applied at the site and diluent water) Oxidation = fully oxidized wastewater treatment, where secondary treatment has dissolved oxygen present Pathogenic microorganism LRV credits can be obtained by a combination of 1) secondary wastewater treatment processes (biological treatment), 2) tertiary recycled water treatment processes 3) chemical disinfection, 4) advanced treatment (MF/RO/UV/AOP) and 5) aquifer retention time. An individual treatment process cannot be credited with more than 6-log removal credits for any of the indicator pathogens, and at least three processes must be credited with at least 1-log removal credit. For surface spreading, the amount of virus removal credit that can be achieved with aquifer retention time can be greater than 6-log removal credits. If FAT is utilized for the entire recharged supply, it is possible to petition for an alternative travel time requirement that is less than 6 months, down to a minimum of 2 months, if all other water quality objectives (WQO) and pathogenic control requirements are met. Table 5-3 lists the typical removal credits for direct injection with FAT.
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Aquifer
Retention Time
Credit(a) Total(b)
LRV
Requirement
Virus 0 1.5 – 2 6 4.5 – 6 12 – 13.5 12
Giardia 4 1.5 – 2 6 0 11.5 – 12 10
Cryptosporidium 4 1.5 – 2 6 0 11.5 – 12 10
Notes: DDW = Division of Drinking Water;
(a) The LRV credit received will depend on the method to estimate underground travel time. (b) The addition of free chlorine can add another treatment process and increase the LRVs and provide added buffer to meeting the LRV requirements
The pathogen removal credit for aquifer retention time is calculated as underground travel time (months) multiplied by a factor based on the method used to estimate travel time. For example, using an extrinsic tracer study, intrinsic tracer study and a numerical model method would receive a credit of up to 1.0-log, 0.67-log and 0.5-log virus removal per month underground retention time, respectively. Thus, in order to receive 6-log pathogen removal credits, the extrinsic tracer study, intrinsic tracer study and numerical modelling methods would need to demonstrate 6-months, 9-months and 12-months of underground travel time, respectively.
Extrinsic tracer studies are expensive and take time, thus municipalities tend towards trying to demonstrate a longer travel time using the lower factor methodology (numerical modelling) to achieve the necessary pathogen removal credit for aquifer retention time.
Other requirements include nutrient reduction based on groundwater quality objectives and compliance with regulated compounds such as:
NDMA ~ 10 ng/L California notification limit
Other CECs with regulatory notification limits (e.g. 1,4-Dioxane) Title 22 drinking water primary and secondary MCL’s
Disinfection Byproducts – i.e. HAAs, THMs, chlorite
For the City to implement a GRR project, purified water would need to be injected into the Smith River Plain Groundwater Basin and achieve the required detention time. Since it does not appear that the groundwater levels at the SRPGB are increasing or decreasing, a GRR project does not seem a good application at this time as there might not be capacity in the basin for injection of purified water with sufficient detention time to meet the regulatory requirements.
Groundwater modeling would be required to determine the feasibility of implementing a GRR project at the SRPGB if pursued in the future.
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5.4.3 Surface Water Augmentation Treatment Requirements A SWA is the use of recycled municipal wastewater for the purpose of augmenting a reservoir that is designated as a source of domestic water supply. The Final SWA regulations adopted on March 6, 2018 include minimum retention time and dilution requirements:
1. An initial reservoir retention time of 180 days must be demonstrated, with flexibility for an alternative minimum theoretical retention time as low as 60 days on a case-by-case basis with State Board approval. SWA projects with minimum retention times of less than 120 days must provide an additional 1-log treatment.
2. The dilution requirement in the reservoir is 100:1 (one percent by volume), or 10:1 (ten percent by volume) with an additional 1-log microbial pathogen treatment, to demonstrate the percent of recycled water withdrawn from the reservoir, by volume, during any 24-hour period.
A project that delivers recycled water to a surface water reservoir, with the reservoir providing some benefits, but lacking the ability to meet the minimum retention time and dilution requirements defined in the Final SWA regulations would be considered direct potable reuse and is referred to as “Raw Water Augmentation”, as indicated in Figure 5-3. However, the Final SWA Regulations include an “alternatives clause,” similar to the GRR Regulations. The intent of an “alternatives clause” is to provide adaptability to offer alternative permitting pathways for innovative projects that build off the expanding knowledge base (Trussell 2016).
Alternative approaches could apply to the treatment train, monitoring plan, or approaches used to demonstrate meeting minimum retention time (as noted in item 1 above). The Final SWA Regulations include language that allows for alternative approaches if it can be demonstrated to the State Board that the proposed alternative provides equivalent or better performance. Written approval from the State Board would be requested prior to implementation, and in some cases a public hearing may be required.
In addition, the Final SWA Regulations establish requirements for:
• Recycled water source control
• Treatment and pathogen removal
• Demonstration testing
• Operations and maintenance
• Effluent and process monitoring and reporting
• Reliability and redundancy
• Identification and responses to failure events
• Reservoir dilution, retention, tracer studies, and monitoring • Public comment and notification
A SWA project would likely be implemented within two key permits:
• DDW drinking water supply permit
• NPDES permit issued by the Regional Board on behalf of the U.S. Environmental Protection Agency (EPA)
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The Regional Board regulates discharges of recycled water to surface waters on behalf of the EPA through the issuance of NPDES permits. NPDES permits implement applicable state and federal water quality standards, policies, provisions, and prohibitions. NPDES permits would also incorporate applicable recycled water and SWA requirements.
Similar to the GRR Regulations, the treatment requirements for SWA require recycled water to be treated by FAT prior to delivery to a reservoir. The treatment train must achieve a minimum of 8/7/8 microbial log-removal for V/G/C, with at least two separate treatment processes credited with no less than 1.0-log removal, and no separate treatment process credited with more than 6-log removal. The SWA Regulations require that any 24-hour input of recycled water into a reservoir must be mixed such that water withdrawn for use as drinking water never contains more than 1% recycled water.
For those projects where recycled water delivered to a reservoir during any 24-hour period makes up 10% of water withdrawn for use as drinking water, the recycled water treatment train must achieve an additional 1-log removal (i.e., 9/8/9) with at least three separate treatment processes credited with no less than 1.0-log removal. In addition, although alternative minimum reservoir retention times as low as 60 days may be considered, SWA projects with minimum retention times of less than 120 days must provide an additional 1-log treatment. The SWA criteria and treatment requirements are summarized in Table 5-4.
Table 5-4. SWA Criteria and Treatment Requirements
Retention
Time
(days)1
Dilution
(Volume: Inflowday)
2 Log Removal at
AWPF (V/G/C)3
# of Treatment
Processes
> 120 100:1 8/7/8 2
10:1 9/8/9 3
> 60 100:1 > 9/8/9 2
10:1 > 10/9/10 3 1 Retention time is calculated as total volume divided by total outflow 2 Dilution of 100:1 = one percent, by volume, of purified water delivered to the surface water reservoir during any 24-hour period. Dilution of 10:1 = ten percent, by volume, of purified water delivered to the surface water reservoir during any 24-hour period 3 Removal credits at a drinking water treatment plant (4/3/2 V/G/C) were previously included in the total log reduction values (LRV) requirement in prior versions of the SWA Regulations but are not included in the Final SWA Regulations.
Anticipated pathogen removal credits for SWA treatment train processes are shown in Table 5-5.
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UV/
AOP
Free
Chlorine
Required
Prior
Discharge
Total Prior
to
Discharge
Total
after
DWTP(a)
Virus 0-4 1.5-3.5 6 4-6 8 11.5-19.5 13.5-
21.5 Giardia 4 1.5-3.5 6 0-3 7 11.5-16.5 14.0-
19.0 Cryptosporidium 4 1.5-3.5 6 0 8 11.5-13.5 13.5-
15.5 Note: The ultimate inactivation credit achieved for a given process may be based on site-specific performance and/or a negotiated validation approach with DDW on a case-by-case basis (WateReuse 2016). This table does not include the potential LRV credits for tertiary filtration, which could add up to 2/2.5/2 credits if approved by DDW. (7) Log reduction credit of 4/3/2 for V/G/C is based on credit achieved through filtration at a conventional drinking WTP (2/2.5/2).
The ultimate inactivation credit achieved may be based on site-specific performance and/or a negotiated validation approach with DDW on a case-by-case basis. For example, the tertiary treatment process prior to the AWPF may receive additional inactivation credits for V/G/C and multiple disinfection processes, such as ozone and free chlorine in addition to UV-AOP, could provide for an additional 4 to 6 virus inactivation credits, respectively. Critical control points identified between individual treatment processes can provide both process control and be used to establish log reduction credits (WateReuse 2016).
The proposed treatment system concept for SWA in the City, assuming the approval of additional inactivation credits such as free chlorine as shown in Table 5-5, would be able to achieve the LRV requirements for V/G/C for any combination of retention and dilution, as shown in Table 5-4. The downstream drinking water treatment plant (WTP) would provide an additional buffer, but credits for log virus removal are no longer assigned in the regulatory framework.
For the City to implement a SWA project, purified water would need to be blended into a surface water reservoir and achieve the required detention time, prior to being treated at a Water treatment facility. Since there is no surface water reservoir in Crescent City, and the potable water treatment system only consists of chlorination as referenced in Section 3.3, a SWA project is not feasible for the City to implement at this time.
5.4.4 Direct Potable Reuse Treatment Requirements
A DPR project is defined as the planned introduction of recycled water either directly into a public water system (treated water augmentation) or into a raw water supply immediately upstream of a water treatment plant (raw water augmentation). Thus, DPR has a spectrum of alternatives with significant differences in the “directness” they seek. As noted in the prior section, a reservoir that is too small to comply with the SWA criteria would be considered a DPR project that introduces recycled water into the raw water supply.
Currently, raw water and treated water augmentation are not yet included as allowable use in California, though a report released by the State Board on December 26, 2016 concluded that it Crescent City Recycled Water Feasibility Study (RWFS) Page 63 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx is feasible to develop and adopt regulations for raw water and treated drinking water augmentation, provided that certain research and key knowledge gaps are addressed8. AB 574, signed on July 5, 2017, further required the State Board to adopt uniform water recycling criteria for potable reuse through raw water augmentation on or before December 31, 2022. The SWRCB published a proposed framework for regulating DPR (SWRCB 2018), which evaluated how public health threats, risk management opportunities and permitting options vary between the range of potable reuse forms and how public health must and will be protected in all cases.
The Framework also sets forth a schedule for completing the recommended research from the prior investigation of developing raw water augmentation criteria (WateReuse 2016). There is currently not an anticipated timeline for the development of uniform water recycling criteria for potable reuse through treated drinking water augmentation.
The concept of DPR is fairly new and untested in California. As a result, there is very little data on DPR design, performance, and safety. Although the criteria for a DPR treatment train have yet to be established in California, the treatment requirements will at a minimum require recycled water to be treated by full advanced treatment (i.e., RO and an AOP) prior to delivery to a raw water or treated water distribution system. The treatment train will likely be required to achieve more than the minimum of 8/7/8 microbial log-removal for virus, Giardia, and Cryptosporidium (V/G/C) required for a SWA project and likely greater than or equal to a 12/10/10 requirement for a GRR project. There will also likely be a requirement that least two separate treatment processes credited with no less than 1.0-log removal, and no separate treatment process credited with more than 6-log removal would be required.
The ultimate inactivation credit achieved may be based on site-specific performance and/or a negotiated validation approach with DDW on a case-by-case basis. For example, the tertiary treatment process prior to the AWTF may receive additional inactivation credits for V/G/C and multiple disinfection processes, such as ozone and free chlorine in addition to UV-AOP, could provide for additional inactivation credits. Critical control points identified between individual treatment processes can provide both process control and be used to establish log reduction credits (WateReuse 2016). Although it has not yet been defined, it is possible that DPR projects will require enhanced monitoring and source control programs as compared to potable reuse projects that include an environmental buffer.
The WateReuse Research Foundation (WRRF) has created a keystone project that seeks to tie together many of the findings from the last six years of potable reuse research. This project is WRRF 14-12, entitled “Demonstrating Redundancy and Monitoring to Achieve Reliable Potable Reuse”. This project utilized a 1.6-mgd demonstration project at the City of San Diego’s North City Water Reclamation Plant. WRRF 14-12 has developed a DPR conceptual process train that augments both the treatment protection and the monitoring to demonstrable performance of a DPR train. The treatment train used in WRRF 14-12 uses full advanced treatment with the addition of ozone and BAC as pretreatment. A range of potential LRV credits for FAT with ozone and BAC is provided in Table 5-6.
8 State Board Press Release
https://www.waterboards.ca.gov/press_room/press_releases/2016/pr122916_dpr_report.pdf Crescent City Recycled Water Feasibility Study (RWFS) Page 64 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx Table 5-6. Potential Pathogen LRV Credits for DPR with Full Advanced Treatment Pathogen MF RO
UV/
AOP
Free
Chlorine Ozone BAC Total
Virus 0-4 1.5-3.5 6 4-6 1-6 unknown 12.5-25.5
Giardia 4 1.5-3.5 6 0-3 1-6 unknown 12.5-22.5
Cryptosporidium 4 1.5-3.5 6 0 1-3 unknown 12.5-16.5
Note: The ultimate inactivation credit achieved for a given process may be based on site-specific performance and/or a negotiated validation approach with DDW on a case-by-case basis (WateReuse 2016). This table does not include the potential LRV credits for tertiary filtration, which could add up to 2/2.5/2 credits if approved by DDW.
For the City to implement a DPR project, purified water would need to be blended into a surface water reservoir (raw water augmentation) or injected directly into the potable water system.
Since there is no surface water reservoir in Crescent City raw water augmentation is not feasible at this time. For treated water augmentation the requirements are not yet fully determined so the feasibility of a DPR project was not evaluated at this time.
5.4.5 Brine Disposal Requirements
The advanced treatment of wastewater for potable reuse using an RO membrane would produce a brine or concentrate for disposal. Typically, brine from the RO train would be blended with secondary wastewater and discharged via the City’s existing ocean outfall pipeline to the Pacific Ocean. Several issues need to be considered for discharges to the Pacific Ocean. These include TDS concentration in the brine relative to the receiving waters; toxicity issues related to the concentration of some constituents (like arsenic); and initial dilution requirements of the existing permit.
5.5 Streamflow Augmentation Treatment Requirement
There are currently no regulatory requirements and/or criteria for the beneficial use of recycled water for streamflow augmentation in California. Any discharge to navigable surface waters would require an NPDES permit from the RWQCB. The potential market opportunity for streamflow augmentation is not considered for this RWFS.
5.6 Summary of Treatment Process and Credits
The SWRCB allocates treatment credits—calculated as log reduction values or LRVs—on a case-by-case basis for each project. Factors discussed in this section that may influence the LRV that is credited for a given unit process include the type of monitoring provided and the performance of the unit process. This section describes the treatment processes used in water reuse applications, and the credits that have been awarded for past projects. Table 5-7 summarizes the treatment processes considered for this study.
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Treatment
Process Description
Tertiary
Filtration
A common wastewater treatment process that provides filtration to remove suspended solids and other pollutants using sand or media filtration. Specific filtration processes approved by DDW (DDW 2014) to meet the performance criteria for Title 22 application for unrestricted reuse include specific cloth, disc, drum and media filters along with membrane-based separation processes (described below).
Nitrifying
Biological
Aerated
Filter (nBAF)
A biological aerated filter (BAF) is a tertiary treatment process with a submerged bed of relatively small size filter media with a high surface area to grow a biomass. A nBAF technology is focused on reducing ammonia and nitrite levels and may provide some reduction of organic carbon and solids. BAF and nBAF are not approved Title 22 applications for unrestricted reuse.
Microfiltration/
Ultrafiltration
(MF/UF)
A membrane-based, pressure-driven separation process that provides a barrier to the passage of solids and microorganisms. MF/UF does not remove salts (i.e., TDS) or other dissolved constituents like ammonia. For potable reuse applications, the primary goal of MF/UF is to provide pre-treatment for the RO membranes, and to remove suspended particulate matter.
Membrane
Bioreactors
(MBR)
A MBR combines a bioreactor and microfiltration into one-unit process. The microfiltration membrane (cassette) is submerged in the bioreactor and a vacuum draws the water through the membrane. MBRs are currently used in non-potable applications in California but have thus far not been utilized for potable reuse.
Reverse
Osmosis (RO)
A membrane-based, pressure-driven separation process that provides a barrier to the passage of dissolved salts, particles, colloids, organics, bacteria, and pathogens. RO produces a very low-TDS product stream and a concentrate stream using a high-pressure membrane separation process. Initially, RO was considered to be completely effective at removing all pathogens and chemicals; however, with improving analytical methods, trace organic compounds have been detected in RO permeate. This gave rise to the required advanced oxidation process following RO (discussed below).
Ultraviolet (UV)
Disinfection
Transfers electromagnetic energy from a mercury arc lamp to water, emitting a broad spectrum of radiation with intense peaks at certain wavelengths. UV light penetrates an organism’s cell walls and disrupts the cell’s genetic material, making reproduction impossible. With the proper dosage, UV irradiation has proven to be an effective disinfectant for bacteria, protozoa, and viruses in water, while not contributing to the formation of disinfection byproducts (DBPs).
UV-based
Advanced
Oxidation
Process (AOP)
Transfers electromagnetic energy from a mercury arc lamp to an auxiliary oxidant that has been added to the wastewater, such as hydrogen peroxide, ozone or chlorine. Photo-excited oxidants quickly degrade to form highly reactive free radicals, which are strong oxidants capable of degrading most natural and synthetic organic compounds present in wastewater. The design of a UV-AOP typically requires UV doses in great excess of those needed for disinfection alone.
Ozone To generate ozone (O3), energy is added to oxygen (O2), splitting the molecules into individual atoms which then collide with oxygen forming ozone. Ozone is then bubbled into water where it will oxidize certain contaminants.
No permitted projects have utilized ozone as a pathogen barrier for potable reuse; however, drinking water systems have received pathogen inactivation credits based on the ozone dose applied.
Biological
activated carbon
(BAC)
A biologically enhanced carbon process that combines ozonation and granular activated carbon (GAC) to remove dissolved organics through adsorption by the activated carbon and biodegradation of bacteria attached on the activated carbon. BAC has not been used in a full-scale potable reuse project in California to date but is currently being pursued for the City of San Diego’s SWA project.
Chlorine-based
Disinfection
The most common disinfection technology in wastewater treatment and reuse. Chlorine inactivates a diverse group of pathogens, including viruses, and residual chlorine prevents pathogen re-growth during storage and distribution. Free chlorine disinfection can be implemented to achieve virus and Giardia credits at multiple places in a potable reuse treatment train. Currently, California water recycling regulations do not differentiate between free and combined chlorine disinfection.
Crescent City Recycled Water Feasibility Study (RWFS) Page 66 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx Anticipated pathogen removal credits for treatment train processes are shown in Table 5-8. The ultimate inactivation credit achieved may be based on site-specific performance and/or a negotiated validation approach with DDW on a case-by-case basis. For example, the tertiary treatment process prior to the AWTF may receive additional inactivation credits for V/G/C and multiple disinfection processes, such as ozone and free chlorine in addition to UV-AOP, could provide for additional inactivation credits. Critical control points identified between individual treatment processes can provide both process control and be used to establish log reduction credits (WateReuse 2016).Table 5-8 can be used as a guide for planning purposes; however, it should be recognized that DDW allocates treatment credits on a case-by-case basis for each project based on monitoring provided and the performance of the unit process.
Table 5-8. Summary of Potential LRV Credits for Unit Treatment Processes Virus Giardia Cryptosporidium
Wastewater Treatment
Tertiary Filtration a 0–2 0–2.5 0–2
MBR b Unknown Unknown Unknown
nBAF c Unknown Unknown Unknown
Membrane Filtration d 0–4 4 4
Reverse Osmosis e 1.5 – 3.5 1.5 – 3.5 1.5 – 3.5
UV and AOP
UV low dose 0.5 – 4 4 4
UV high dose with AOP 6 6 6
Ozone f 1-6 1-6 1-3
BAC g Unknown Unknown Unknown
Free Chlorine 4-6 0-3 0
Surface Water Treatment Plant 4 3 2
The ultimate inactivation credit achieved for a given process may be based on site-specific performance and/or a negotiated validation approach with DDW on a case-by-case basis (WateReuse 2016). a Through sand filtration Olivieri et al. (2016) b MBRs have not been credited for pathogen removal performance in potable reuse in California but could receive up to 2/2/2. c nBAF is not currently listed as an approved T22 tertiary treatment process d Protozoa removal based on EPA (2005). e Most potable reuse facilities receive between 1 and 2 LRV credit, though options for higher credits are being pursued. f None of the permitted potable reuse projects utilize ozone disinfection, though projects under development will pursue ozone credit. g While removal credits for BAC may be attainable, none of the existing or planned projects in California are seeking LRV credit for this process.
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5.7 Summary of Non-Potable and Potable Reuse
There are a wide range of non-potable and potable reuse scenarios, with growing acceptance from the industry, regulators, and the public to allow for an increasingly more diverse range of opportunities to beneficially reuse wastewater. There are many factors that should be considered in evaluating non-potable and potable reuse opportunities, which include recognizing the benefits and risks of pursuing different forms of reuse. Table 5-9 provides a summary of the types of water reuse discussed in this section, and pros and cons associated with each type.
Table 5-9. Summary of Pros and Cons for Each Reuse Type Non-Potable Pros Cons
Undisinfected Secondary • Requires no modifications to
Crescent City Wastewater
Treatment Facility
• Restricted end uses
• Public perception is uncertain
Disinfected – 23 Secondary • Requires only the implementation of disinfection at Crescent City WWTF
Disinfected – 2.2 Secondary • Requires only the implementation of disinfection at Crescent City WWTF
• Somewhat restricted end uses
• Public perception is uncertain
Disinfected Tertiary • Unrestricted end uses for nonpotable applications • Public perception is uncertain
IPR Pros Cons
GRR through Surface
Spreading
• Requires the least amount of aboveground treatment for potable reuse • Been in practice in CA for over 50-
yrs
• General public perception is o.k.
• Finalized regulations exist
• Infiltration removes some CECs
• Requires large land area for
surface spreading
• Requires access to drinking
water aquifer large enough to
meet project demands
• Does not remove all CECs
GRR through Subsurface
Injection
• Requires less land area than
spreading
• Been in practice in CA for over 40-
yrs
• General public perception is o.k.
• Finalized regulations exist
• Removes majority of known CECs
to below the very low detection limit
ranges
• Requires additional treatment
beyond what is required for
surface spreading: RO and
UV/AOP
• Requires access to drinking
water aquifer large enough to
meet demand needs
Surface Water
Augmentation
• Offers an alternative to communities
without access to an aquifer
• Draft regulations released
• Multiple projects currently being
pursued in CA
• Removes majority of known CECs
to below very low detection limit
• No existing local project in
operation
• Requires access to drinking
water reservoir that meets
dilution requirements
• Public perception is less certain
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Raw Water Augmentation
using a reservoir
• Similar to SWA and therefore easier
to implement than more direct types
• Offers an alternative to communities
without access to an aquifer or
reservoir that meets
dilution/retention time requirements
• Removes majority of known CECs
to below very low detection limit
• No existing local project in
operation
• Regulations are being
developed
• Public perception is less certain
AWT water as an approved
drinking water supply
• Offers an alternative to communities
without access to any form of
engineered or environmental buffer
• Potentially lower costs due to
reduced infrastructure needs
• Greatest potential for wide
geographic distribution
• Removes majority of known CECs
to below very low detection limit
• Shortest response times will
necessitate strict requirements
for treatment, monitoring, failure
response, etc.
• No existing local project in
operation
• Regulations are being
developed
• Likely years away from project
implementation
• Public perception is less certain
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As mentioned previously in this RWFS, all water demands for the City of Crescent City are met through potable water; recycled water is currently not produced or used. One of the objectives of this study is to identify the potential market for recycled water use and evaluate the feasibility of recycled water use within the City. The following sections describe the approach and findings of the non-potable and potable reuse market assessments within the study area boundary.
6.1 Market Assessment Approach
The market assessment approach was performed in two parts.
1. Non-Potable Market Approach: Non-potable demands were assessed based on annual meter data provided by the City as well as estimated for irrigation demands. Peak demands were estimated using peaking factors. Irrigation demands peak in the summer months while commercial and industrial demands are relatively constant throughout the year. Thus, the ability to meet non-potable demands is assessed based on the available supply in the summer months when irrigation demands are at their peak.
2. Potable Market Approach: Potable demand requirements are not based on meter data, but rather the capacity of a suitable environmental buffer and/or future potable water demands.
a. Indirect potable demand for groundwater recharge is based on the available capacity of identified aquifers to receive recycled water while meeting regulatory requirements for retention (response) time.
b. Indirect potable demand for surface water augmentation is based on the available capacity of a local reservoir to receive recycled water while meeting regulatory requirements for retention time.
c. Direct potable demand for recycled water is based on future potable demands in Crescent City’s service area.
Indoor potable demands are assumed to be relatively constant throughout the year and the available supply of advanced treated water in the summer months, when wastewater production is the lowest, would limit the size of a DPR project for the City.
6.2 Non-Potable Reuse (NPR) Market Assessment
Non-potable reuse is the use of treated wastewater or treated industrial process wastewater for a specific purpose other than drinking. Potential non-potable demands include irrigation demands (such as for parks, medians, golf courses, or other similar irrigated areas), commercial and industrial demands (such as for local breweries or food processors for landscape irrigation, toilet flushing, process water for manufacturing, cooling, heating, and cleaning, and other uses), and other demands such as sewer flushing, construction dust control, agricultural use, and environmental benefits.
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6.2.1 Identifying Potential Recycled Water Users
Potential recycled water users within the City were initially identified through conversations with City staff, and preliminary research of the study area using Google Earth aerial imagery. Initial potential recycled water users identified for this study were as follows:
• City parks, cemeteries, schools, and landscape areas for irrigation • Truck Fill station (for dust control, construction uses, sewer flushing, agricultural use, or homeowners’ irrigation)
• Elk Valley Rancheria (for casino landscape irrigation, toilet flushing, water features) • Industrial users (breweries, cannabis and food processors) • CSA partnership
• Del Norte County Regional Airport
• Pelican Bay State Prison
After discussions with City staff about the feasibility of the above-mentioned recycled water customers, engagements were made with these potential customers and their representatives to discuss potential interest. Table 6-1 summarizes inquiries made.
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Potential User of
Recycled Water Initiator
Potential Recycled
Water Demand
Entities Gauged Interest/
Response
Rumiano Cheese
Company Crescent City None
Potential interest in reusing
industrial treated and
disinfected effluent.
Seaquake Brewing N/A Minimal non-potable
demand
Not contacted due to small
demand volume.
Port O’Pints Brewing N/A Minimal non-potable
demand
Not contacted due to small
demand volume.
Cannabis Grow Houses N/A Unknown nonpotable demand
Not contacted since these
facilities have not been
permitted yet.
Pelican Bay Prison N/A None
Pelican Bay Prison has its own
wastewater treatment system
and has no use for recycled
water. This is a maximumsecurity facility so a project is unlikely. No contact was made.
Crescent City Parks Crescent City Park irrigation Potential irrigation demands.
CSA Partnership Crescent City None
No immediate needs for
recycled water were identified
and no contact was made.
Del Norte County
Regional Airport N/A None
No immediate needs for
recycled water were identified
and no contact was made.
Elk Valley Rancheria Crescent City None No immediate needs were confirmed at this time.
Crescent Elk Middle
School Crescent City Potential irrigation demands
School District Facilities
Director had a previous
experience where recycled
water fee rates were
unexpectedly higher than
potable water fee rates for
irrigation purposes. School
District would prefer to
continue using potable water
for summer irrigation demands
and not plan for recycled water
use due to unknowns and
uncertainties around recycled
water fee rates.
Joe Hamilton
Elementary School Crescent City Potential irrigation demands Del Norte High School Crescent City Potential irrigation demands
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6.2.2 Non-Potable Recycled Water Demand
This section describes the calculation of demand for recycled water for each identified potential customer. Locations of potential customers and their associated calculated irrigation demand are shown on Figure 6-1 and Figure 6-2. The customers described below and in Table 6-3 comprise the non-potable recycled water market within the study area boundary.
6.2.2.1 Irrigation Demands
The City provided 2018 water meter data included in Appendix C, however, discrepancies were identified within the data set (i.e. unmetered parks and differences in water usage types covered by one meter). Based on further discussions with the City, it was agreed that irrigation demand would be calculated using historical evapotranspiration and precipitation data for consistency across all irrigation demand estimates. Irrigation demand was assumed to be the difference between monthly evapotranspiration and precipitation, as shown in Table 6-2. $+
$+
Q3
Rumiano
Port O'Pints
Pyke Field
3.91 B. Jonathan
Park
0.94 WWTP
1.44 Point of
Honor
3.16 B. Jonathan
Cem.
2.36 C. Elk
Garden
0.31 Christ
0.64 New Life
0.34 Nazarene
0.44 St. Joseph
0.96 Seabreeze
0.45 SeaQuake
0.25 Lighthouse RV
0.88 Seagull
0.82 Cannabis
1 & 2
2.86 Beach
Front
30.23 Peterson
5.59 400 E
Cooper
13.1 C. Elk
Middle
9.33 J. Hamilton
8.82 Del Norte
Community
4.47 Del Norte
High
9.81 Fill
Station
5.21 ³ 0 1,000 2,000
Scale: Feet
City of Crescent City
Crescent City, CA
Non-Potable Recycled Water
Demand Market Assessment Map
K/J 2076056*00
August 2022
Figure 6-1
Z:\Projects\CityOfCrescentCity\Events\20211013_RWFS\Fig6-1_MarketAssessmentMap.mxd Date: 8/9/2022 Printed by: MaryEllenMcCarty Legend
Irrigation Demand
Apartment
Cemetary
Church
Industrial - Irrigation
Park
School
Source: Esri, Maxar, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community Size Legend
$+ Industrial - No Demand
Industrial - Other Non-Potable
Q3 Wastewater Treatment Facility
Irrigated Area Footprint
City of Crescent City Boundary
Average Annual Demand (AFY)
0.25 - 1.0
1.0 - 4.0
4.0 - 5.5
5.5 - 13.0
13.0 - 30.2
$+
Q3
Rumiano
Pyke Field
3.91 B. Jonathan
Park
0.94 WWTP
1.44 Point of
Honor
3.16 B. Jonathan
Cem.
2.36 C. Elk
Garden
0.31 Christ
0.64 New Life
0.34 Nazarene
0.44 St. Joseph
0.96 Seabreeze
0.45 SeaQuake
0.25 Lighthouse RV
0.88 Seagull
0.82 Cannabis
1 & 2
2.86 Beach
Front
30.23 Peterson
5.59 C. Elk
Middle
9.33 J. Hamilton
8.82 Fill
Station
5.21 ³ 0 400 800
Scale: Feet
City of Crescent City
Crescent City, CA
Non-Potable Recycled Water Demand
Market Assessment Map, Close-Up
K/J 2076056*00
August 2022
Figure 6-2
Z:\Projects\CityOfCrescentCity\Events\20211013_RWFS\Fig6-2_MarketAssessmentMap-close up.mxd Date: 8/9/2022 Printed by: MaryEllenMcCarty Legend
Irrigation Demand
Apartment
Cemetary
Church
Industrial - Irrigation
Park
School
Source: Esri, Maxar, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community Size Legend
$+ Industrial - No Demand
Industrial - Other Non-Potable
Q3 Wastewater Treatment Facility
Irrigated Area Footprint
City of Crescent City Boundary
Average Annual Demand (AFY)
0.25 - 1.0
1.0 - 4.0
4.0 - 5.5
5.5 - 13.0
13.0 - 30.2
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Average Eto
(in)(a)
Average
Precipitation
(in)(b)
Average
Irrigation
Demand(c) (in)
Dry Year
Irrigation
Demand(d) (in)
Jan 1.56 11.59 0.00 0.00
Feb 1.93 9.82 0.00 0.00
Mar 3.11 9.21 0.00 0.00
Apr 4.09 5.44 0.00 0.00
May 4.50 3.49 1.01 4.50
Jun 4.92 1.64 3.28 4.92
Jul 4.44 0.44 4.00 4.44
Aug 4.21 0.61 3.60 4.21
Sep 3.56 1.81 1.75 3.56
Oct 2.87 5.23 0.00 0.00
Nov 1.84 9.83 0.00 0.00
Dec 1.47 11.65 0.00 0.00
Total 38.50 70.77 13.64 21.63
Average(e) 3.21 5.90 1.14
Peak(f) 4.92 11.65 4.00
Peaking Factor(g) 1.5
Notes:
(a) Data from California Irrigation Management Information System (CIMIS) for Smith River Station (#263), average history from 7 October 2020 to 14 November 2021. The reference ETo data surface is grass. (b) Data from the Western Regional Climate Center for Crescent City, California (042147), period of record from 1 January 1893 to 22 July 2013.
(c) Evapotranspiration minus precipitation.
(d) Evapotranspiration during dry months only. Assumes no precipitation for May through September (e) average ETo, precipitation, and irrigation demand over the entire year. (f) Peak (maximum) ETo, precipitation, and irrigation demand over the entire year. (g) Peak ETo divided by average ETo. This factor is applied to irrigation customers' average demand to estimate their peak irrigation demand.
As shown in the table, evapotranspiration is higher in summer months when there is less precipitation, resulting in higher irrigation demand. Therefore, for the purposes of this report irrigation demand and recycled water production is only considered for the summer months which is approximately 150 days of the year, or five months.
The annual irrigation demand (inches) was then analyzed for each potential customer identified.
The average annual irrigation demand per customer was assumed to be directly proportionate to the potential customer’s irrigation area, and calculated using the following equation:
𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴 𝑖𝑖 𝑖𝑖 𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖 𝑑𝑑 𝑑𝑑 𝑑𝑑 (𝐴𝐴𝐴𝐴) = 𝐼𝐼 𝐴𝐴𝐴𝐴𝐴𝐴𝐴𝐴 ( 𝑎𝑎 𝑎𝑎) ∗ 𝐼𝐼 𝐷𝐷 (𝑓𝑓 ) ∗ 0.8 ∗ 1.0 The potential irrigated area (in acres) for each customer was estimated using GIS. An irrigation factor of 0.8 was applied to indicate the assumption that only 80% of the area measured would be landscaped and irrigated. This irrigation factor also accounts for the assumption that, due to irrigation distribution uniformity, wind drift, varying plant coefficients, and permeability, irrigation systems are not 100% efficient. A crop coefficient of 1.0 was applied to the demand to conservatively estimate the irrigation demand of the turf or other plants grown in the irrigated Crescent City Recycled Water Feasibility Study (RWFS) Page 76 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx area. The above equation calculates average irrigation demand for a specific month. Unit conversions were applied to calculate the average annual and average day demand.
To calculate peak day demand, a peaking factor of 1.5 was applied to the average demand.
This peaking factor is calculated by dividing the peak evapotranspiration by the average evapotranspiration. Peak hour demand was calculated by applying a peaking factor of 3.0 to the peak day demand. An hourly peaking factor of 3.0 was determined to account for the daily irrigation demand (24 hours) provided by 8 hours of irrigation per day. The calculated irrigation demand for each identified customer is included in Table 6-3. The calculated irrigation demands were compared to the meter data provided by the City for 2018 to confirm that the order of magnitude of the demand for each customer aligned with historical data.
Table 6-3. Calculated Irrigation Demand Summary
Customer
Irrigated
Area
(acres)(a)
Average
Annual
Irrigation
Demand
(AFY)(b),(c),(d)
Average
Day
Irrigation
Demand
(GPD)
e
Peak Day
Irrigation
Demand
(GPD)
(f)
Peak Hour
Irrigation
Demand
(gpm)(g)
Parks and Fields
Pyke Field 4.3 3.9 7,000 11,000 23
Beach Front Park 33 30.2 56,000 85,000 176
Brother Jonathan Park 1.0 0.9 2,000 3,000 5
Peterson Park 6.1 5.6 10,000 16,000 33
Land Adjacent to WWTF 1.6 1.4 3,000 4,000 8
Point of Honor Area 3.5 3.2 6,000 9,000 18
SUB-TOTAL 49.8 45.3 84,000 127,000 264
Cemeteries
Cemetery (400 E Cooper
Ave) 14.4 13.1 25,000 37,000 77
Brother Jonathan Cemetery 2.6 2.4 4,000 7,000 14
SUB-TOTAL 17.0 15.5 29,000 43,000 90
Institutions
Crescent Elk Middle School 10.3 9.3 17,000 26,000 54
Crescent Elk School Garden 0.3 0.3 600 1,000 2
Joe Hamilton Elementary
School 4 3.3 6,000 9,000 19
Church of Christ 0.7 0.6 1,000 2,000 4
New Life Church 0 0.3 600 1,000 2
Church of the Nazarene 0.5 0.4 800 1,200 3
St. Joseph's Catholic School 1 1.0 2,000 3,000 6
Del Norte Community
School 4.9 4.5 8,000 12,000 26
Del Norte High School 11 9.8 18,000 27,000 57
SUB-TOTAL 32.5 29.6 54,000 83,000 173
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Irrigated
Area
(acres)(a)
Average
Annual
Irrigation
Demand
(AFY)(b),(c),(d)
Average
Day
Irrigation
Demand
(GPD)
e
Peak Day
Irrigation
Demand
(GPD)
(f)
Peak Hour
Irrigation
Demand
(gpm)(g)
Apartments and Commercial
Seabreeze Apartments 0.5 0.5 800 1,200 3
SeaQuake Brewing 0.3 0.2 500 750 2
Crescent City RV Park 1.0 0.9 1,600 2,400 5
Seagull Villa Apartments 0.9 0.8 1,500 2,250 5
SUB-TOTAL 2.6 2.4 4,400 6,600 14
Industrial
Recycled Water Truck-Fill
Station(h) - 5.2 4,000 - -
Future Cannabis Grow
Houses(j) - 2.9 2,000 - -
SUB-TOTAL - 8.1 6,000 - -
IRRIGATION DEMAND
TOTAL 102 101 180,000 260,000 540
Notes:
(a) Area approximated using ArcGIS.
(b) Assumes an Irrigation Efficiency of 80%. This indicates that only 80% of the area measured is landscaped and irrigated. Due to irrigation distribution uniformity, wind drift, varying plant coefficients, soil permeability, and other management factors, irrigation systems are not 100% efficient. (c) It is assumed the crops for each of the users is entirely turf grass. A crop coefficient of 1 is applied to conservatively estimate irrigation demand from the evapotranspiration values from Table 1. (d) Average Annual Irrigation Demand = Irrigated Area x Irrigation demand x Irrigation Efficiency x Crop Coefficient.
(e) Average Day Irrigation Demand = Average Annual Irrigation Demand / # of irrigation days (assume 150 days for Crescent City).
(f) Peak Day Irrigation Demand = Average Day Irrigation Demand in Peak Month = Average Day Irrigation Demand x Peaking Factor (Peaking Factor = 1.5).
(g) Peak Hour Irrigation Demand = Peak Day Irrigation Demand (GPD) x 3 (Peaking factor based on 24 hours of flow condensed into 8 hours of irrigation in a day), converted to gallons per minute (gpm). (h) Recycled Water Truck-Fill Station based on an estimate of 4,000 gallons per truck, 1 truck per day, 150 days per year.
(i) Future Cannabis Grow House demand based on estimate of 200 gallons per square foot per year (for indoor farming), and two 2,000 square foot facilities.
6.2.2.2 Potential Industrial Users
The potential industrial customers of recycled water include future cannabis grow houses, SeaQuake brewery, Port O’ Pints Brewery, and Rumiano Cheese Company (Rumiano).
The estimated demand for the future cannabis grow houses was based on an estimate of 200 gallons per square foot per year of water required for indoor farming (New Frontier Data, 2021). The future cannabis grow house facility footprint was estimated to be approximately 2,000 square feet each. The calculated demand is included in Table 6-3.
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After discussion with the City and Rumiano staff, it was determined that Rumiano does not have a demand for recycled water use on site. However, based on the treatment train, flow volume, and effluent water quality previously discussed in Section 4.5.1, Rumiano has the potential to become a supplier of recycled water for nearby irrigation users. This is discussed in more detail in Section 7 and Section 8.
6.2.2.3 Potential Other Users
The potential need for a truck fill station for dust control, other construction use, or for local homeowner’s irrigation was identified by the City. The estimated demand for the truck fill station was based on approximately 4,000 gallons per truck, and an assumption of 1 truck per day, 150 days of the year. The truck fill station could also be used for sewer flushing by the City and for agricultural users. The calculated demand is included in Table 6-3.
6.3 Potable Reuse Market Assessment
The potable reuse options considered for this study include indirect potable reuse and direct potable reuse. As noted previously in this study and in the 2020 Urban Water Master Plan, there are no foreseeable constraints on Crescent City’s water supply, therefore, these concepts were studied using a qualitative approach to assess opportunities of potable reuse for the City’s service area.
6.3.1 Indirect Potable Reuse (IPR)
Indirect potable reuse is one of the pathways for potable reuse by augmenting a water supply that is used for drinking and other purposes with highly treated municipal wastewater. There are two types of IPR projects: Groundwater Replenishment Reuse (GRR) and Surface Water Source Augmentation (SWA) projects, as described in detail in Section 5.4.
GRR projects require injection of purified water into a groundwater aquifer, where it mixes and assimilates with native groundwater. The groundwater aquifer acts as an environmental buffer for the recycled water prior to extraction and the recycled water becomes a source of water supply. The only potential option for groundwater replenishment within the Crescent City area is replenishment of the Smith River Plain Groundwater Basin. Per the analysis done in the 2020 Urban Water Master Plan, groundwater elevations within the SRPGB have been stable since the 1950’s, despite experiencing the driest years on record. As noted previously, there is not a projected decrease in annual precipitation for the region and population demand is projected to decrease, as described in Section 3.5. With the consideration of these factors, groundwater replenishment is not a feasible option for indirect potable reuse in Crescent City at this time and was not investigated any further.
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6.3.2 Direct Potable Reuse (DPR)
Direct potable reuse is the third pathway for potable reuse. DPR is the introduction of recycled water either directly into a public drinking water system, or into a raw water supply immediately upstream of a drinking water treatment plant. Due to the high quality of the groundwater underflow of the Smith River, the City of Crescent City does not own or operate a Water Treatment Plant. The City only provides disinfection to produce potable water. The City does not have a facility or the space to construct an advanced water treatment facility and has no plans to build a Water Treatment Facility. Therefore, direct potable reuse is not considered a viable option at this time and was not researched further for the purposes of this study.
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7.1 Preliminary Screening Criteria and Results
After identifying potential recycled water users as summarized in Table 6-1 and their irrigation demands as described in Section 6.2.2, the potential recycled water users were narrowed down further based on the following screening criteria:
1) Customer’s interest in utilizing recycled water.
2) Customer’s total demand for recycled water.
3) Proximity to source of recycled water.
4) Availability of recycled water to meet customer demands. 5) Environmental considerations.
Details on the screening of potential recycled water customers using the selected criteria are included in the following subsections.
7.1.1 Customer’s Interest
Potential recycled water customers were removed from consideration if they were not interested in using recycled water on their property or did not have a need for recycled water at this time.
As discussed in Section 6.2 and noted in Table 6-1, various entities did not express interest in using recycled water or did not identify a need for it. The following potential recycled water users were removed from consideration for this study:
1) Crescent City Schools: Del Norte Community School, Del Norte High School, Joe Hamilton Elementary School, and Crescent Elk Middle School. 2) Future Cannabis Grow House: does not have a need for recycled water at this time as their facilities have not been permitted for construction yet and are therefore too far out from operation to consider.
7.1.2 Total Demand
Customers with recycled water demand less than 1 AFY were removed from consideration due to the likely large cost-benefit ratio of implementing a recycled water project. The costs of implementing a recycled water project for customers with small demands would likely result in financial burden and outweigh the benefits. Customers with less than 1 AFY demand included churches and apartments.
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7.1.3 Proximity to Recycled Water Source
Proximity to the recycled water source increases the feasibility of implementation of a recycled water project due to the reduced amount of infrastructure needed. The two potential facilities for recycled water sources identified within the City are the WWTF and Rumiano, as discussed in Section 4. The following customers were considered too far from these facilities and were removed for consideration: 400 E Cooper Ave Cemetery, Pyke Field, and Brother Jonathan Cemetery. In contrast, Beach Front Park and Peterson Park are close to the WWTF and Rumiano, respectively. Therefore, both parks were identified as feasible recycled water customers.
7.1.4 Availability of Recycled Water
The volume of recycled water produced is a limiting factor for recycled water customers. If a customer’s demand exceeds the recycled water production capacity, the customer’s demand cannot be completely met with recycled water. To analyze if there was sufficient recycled water to meet customer demand, a comparison between the estimated irrigation demands and the volume of recycled water produced at a nearby production location was also completed for selected potential recycled water customers.
Figure 7-1 below shows a comparison of the available recycled water produced at the City WWTF to the calculated monthly irrigation demand at Beach Front Park and Point of Honor. As shown on the graph, Beach Front Park and Point of Honor irrigation demands are depicted below the available recycled water line, therefore, Beach Front Park was confirmed to be a feasible customer of recycled water.
Figure 7-2 shows a comparison of the available treated effluent produced (12,000 gpd) at Rumiano Cheese Company to irrigation demands of nearby customer (Crescent Elk Middle School, Joe Hamilton Elementary School, and Peterson Park). As shown on the graph, Crescent Elk Middle School’s irrigation demand exceeds the 12,000 gpd available from Rumiano, while Joe Hamilton Elementary School’s irrigation demand could be met by the Rumiano treated effluent. However, due to a lack of customer interested, as noted in Section 7.1.1, these schools were removed from consideration. Peterson Park has an irrigation demand below 12,000 gpd during May and September, while exceeding 12,000 gpd during June through August. Although the treated effluent from Rumiano may not be sufficient to meet all demands at Peterson Park during June through August, the demand can be compensated through recycled water storage at the park. A storage tank could store recycled water at the park during months where excess treated effluent is produced, which could supply irrigation demand during months where the treated effluent is not sufficient to meet all demand. In addition, potable water could be supplied to supplement recycled water for park irrigation.
Finally, based on discussions with Rumiano, the cheese company has plans to expand their treatment facilities and increase production, so the volume of treated effluent available may increase in the future. Therefore, Peterson Park was considered a feasible recycled water customer.
0 0.05
0.1 0.15
0.2 0.25
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Average Demand (MGD)
Figure 7‐1. Recycled Water Supply and Demand Analysis for Beach front Park and Point of Honor
Beach Front Park Irrigation Demand Point of Honor Irrigation Demand RW Available for NPR Demand Future RW Available for NPR Demand Notes:1) Irrigation demand estimates based on average ETo and Precipitation for Crescent Cityand the estimated acreage for irrigation. A factor of 80% irrigation efficiency was applied.2) Future RW Available for NPR Demand = after replacement of MBR membranes Recycled Water Supply and Demand Analysis for
Beach Front Park and Point of Honor
Figure 7-1 K/J 2076056*00
September 2022
0 5,000
10,00015,00020,00025,00030,00035,000
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Flowrate (gpd)
Figure 7‐2. Rumiano Average Effluent (gpd) and Nearby Irrigation Demands Crescent Elk Middle Joe Hamilton Elementary Peterson Park Rumiano Polished Effluent (min) Rumiano Treated Effluent Rumiano Average Effluent (gpd)
and Neaby Irrigation Demands
Figure 7-2 K/J 2076056*00
September 2022
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7.1.5 Environmental Considerations
Environmental considerations were also included in the screening of potential recycled water customers. It is expected that environmental impacts would be relatively minor and similar for all projects to be implemented for the potential recycled water users. All projects would include construction of infrastructure required (such as pumps, pipelines, and storage tanks) in existing disturbed areas such as paved roadways and parks. There are no sensitive environmental resources within the identified areas of disturbance or recycled water use. Mitigation for implementation of recycled water is expected to be limited to potential construction stormwater discharges which will be addressed with use of stormwater best management practices.
All project alternatives would provide a source of water for irrigation outside of potable water, increasing the resiliency of the City’s water system, reducing demand on the Smith River, and reducing effluent loads to the Pacific Ocean. The environmental considerations of each project alternative are equivalent as they are to be constructed in areas with existing disturbance and provide similar environmental benefits.
7.1.6 Preliminary Customer Screening Results
After the preliminary screening process the potential recycled water users identified as most feasible for implementation of a recycled water project were Beach Front Park and Peterson Park. The following (3) recycled water project alternatives were developed for this RWFS:
• Project Alternative 1: Irrigation of Beach Front Park • Project Alternative 2: Irrigation of Beach Front Park & Truck Fill Station • Project Alternative 3: Irrigation of Peterson Park
The following sub-sections provide the preliminary design criteria and cost assumptions utilized for developing these project alternatives. Detailed descriptions of each project alternative are presented in Section 8 of this RWFS.
7.2 Preliminary Design Criteria
This section provides a summary of key assumptions and criteria applied to size the facilities required to treat, deliver, convey, and store recycled water. All facility sizing is assumed to be preliminary and would be further evaluated and refined during project design. Costs are provided at a conceptual level, based on industry standard unit costs and recent project experience, to reflect facility requirements and operational activities to produce and deliver recycled water.
7.2.1 Irrigation Demands
Irrigation demands were calculated using historical precipitation and evapotranspiration climate data as discussed previously in Section 6.1.2. Historical precipitation and evapotranspiration Irrigation Demand data indicated that irrigation was only needed for 150 days of the year on average (approximately five months), with the remainder of the year having sufficient rainfall Crescent City Recycled Water Feasibility Study (RWFS) Page 85 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx that no additional irrigation is required. The calculated average day and peak day irrigation demand were used as a basis for the recycled water volume needed to be produced by each treatment system and for sizing conveyance and other infrastructure for each alternative. The calculated irrigation demands for each alternative are summarized in Table 7-1 below.
Table 7-1. Irrigation Demands for Recycled Water Production and Infrastructure Sizing Project Alternative
Average Day
Demand (GPD)
Peak Day
Demand (GPD)
Peak Hour
Demand (GPM)
1- Beach Front Park 56,000 85,000 176
2- Beach Front Park & Fill Stationa 60,000 85,000 176
3- Peterson Park 10,000 16,000 33
Note:
(a) Fill station demand assumes 4,000 gallons per truck, one truck per day, 150 days a year.
7.2.2 Available Recycled Water Production Assumptions
Due to the WWTF influent flow split factors described in Section 4.4 and for the purposes of this study, the following recycled water calculations were performed to confirm what the available MBR effluent could be for producing recycled water after meeting the blending requirements of the MBR and RBC effluents to meet the WWTF’s NPDES discharge requirements. Table 7-2 outlines the following assumptions for successful operation of the treatment plant.
Table 7-2. Recycled Water Production
Project Alternative
1 – Beach
Front Park
2- Beach Front Park
+ Fill Station 3- Peterson Park
Average Day Irrigation Demand 56,000 60,000 10,000
Recycled Water Production a 56,000 60,000 10,000
CC WWTF – Dry Season Flows
Influent Available (gpd) – Dry
Seasonb 1,200,000 1,200,000 N/A
Secondary Influent to RBCs (gpd)c,d 288,000 288,000 N/A Secondary Influent to MBRs (gpd)c,d 672,000 672,000 N/A Tertiary Effluent from MBRs (gpd)e 604,800 604,800 N/A
Tertiary Effluent from MBRs for
Recycled Water Production (gpd)f 56,000 60,000 N/A
Tertiary Effluent from MBRs for
Blending (gpd)g 548,800 548,800 N/A
Industrial Treatment Facility - Rumiano
RO-UV Treatment System Effluenth N/A N/A 30,000
Volume Used for On-Site CIP
systemsi N/A N/A 18,000
Effluent available for RW j N/A N/A 12,000
Notes:
(a) The volume of recycled water produced is adjusted to meet the demand for each alternative. Any tertiary effluent from the MBRs not required for recycled water use will be blended with secondary effluent from the RBCs and discharged to the ocean outfall.
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(e) Membrane bioreactor recovery rate of 90% is assumed. (f) Tertiary effluent from MBRs for recycled water production is assumed equivalent to the average day irrigation demand.
(g) Tertiary Effluent from MBRs for Blending = Tertiary Effluent from MBRs – Tertiary Effluent from MBRs for RW production
(h) Effluent volume from the on-site RO/UV treatment system that is stored in the existing 30,000-gallon Polished Water Silo and used for CIP systems, based on conversations with Rumiano representatives. (i) Effluent volumes used for CIP systems at the facility based on conversations with Rumiano representatives. (j) Remaining RO/UV effluent to be sent to new pump prior to discharge to City sewer and before mixing with effluent from the MBBR/DAF treatment. This is the effluent available for irrigation use.
7.2.3 Facility Sizing Criteria and Assumptions
Facilities required for each project alternative include treatment system upgrades, pumps, conveyance lines, storage tanks, and irrigation systems. All project facilities were sized using either average day irrigation demands, or peak hourly irrigation demands, as appropriate. The following subsections describe the sizing criteria and assumptions used for each type of facility.
7.2.3.1 Treatment Facilities
Treatment facility improvements considered were upgrading the UV disinfection system at the City WWTF as the current UV system installed has not been used and is sized for a larger flow than required for the projects considered. The UV disinfection system upgrades at the City’s WWTF include replacing the membrane reuse pumps, the flow meter, and one of the UV reactors. All equipment to be replaced in the UV disinfection system were sized based on the average day irrigation demand flows. Treatment system upgrades for the City’s WWTF are described in further detail in the Section 8.
It is assumed that the effluent produced at Rumiano Treatment Facility from the RO/UV treatment system would not require further treatment to meet water quality requirements for landscape irrigation. Since the Rumiano industrial effluent is not comingled with the facility sewer there is no blackwater mixed with the industrial effluent. No additional treatment facilities were assumed for Project Alternative 3 for the purposes of this RWFS.
7.2.3.2 Storage Facilities
Storage tanks at Beach Front Park and Peterson Park are required to provide equilibrium storage for the recycled water and to provide pressure requirements for the irrigation systems.
These storage tanks will provide a constant source of irrigation supply when irrigation is required without excessive pumping from the recycled water treatment system. Required storage volume was sized for daily use based on the average day irrigation demand as summarized in Table 7-3 below and sizing criteria will be verified during detailed design.
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Storage Criteria
Description Sizing Criteria Used
Project
Alternative 1
Project
Alternative 2
Project
Alternative 3
Storage Volume
Required 56,000 GPD 60,000 GPD 10,000 GPD
7.2.3.3 Pipelines
Recycled water conveyance pipelines would be required to convey recycled water from the treatment systems to the proposed storage tanks, and from the storage tanks to park irrigation distribution systems. A minimum velocity of 6 feet per second (fps) and the average day irrigation demand flow were used to determine the minimum pipeline diameter for the pipelines from the treatment system to the storage tanks. Conveyance lines from the storage tanks to park irrigation systems were sized using the minimum velocity of 6 fps and peak hourly irrigation demand flow. In addition to the conveyance pipelines, tank overflow piping would be installed to drain to the nearest sewer manhole by gravity. Pipeline sizing assumptions are summarized in Table 7-4 for each project alternative below.
Table 7-4. Pipeline Design Criteria
Pipe Criteria Description Sizing Criteria Used
Project
Alternative 1
Project
Alternative 2
Project
Alternative 3
Design Criteria for Pipelines to
Storage Tanks
Pipe Velocity 6 fps 6 fps 6 fps
Pipe Design Flow (Average Day) 56,000 GPD 60,000 GPD 10,000 GPD Design Criteria for Pipelines to
Park Irrigation Systems
Pipe Velocity 6 fps 6 fps 6 fps
Pipe Design Flow (Peak Hourly) 85,000 GPD 85,000 GPD 16,000 GPD
7.2.3.4 Pumps
Pumps were assumed to be required at the treatment systems to pump recycled water to the storage tanks. Pumps were also assumed to be required at storage tanks to pump recycled water to the park irrigation systems. No pump redundancy was assumed but may be included in future design plans if desired. Pump total dynamic head (TDH) was calculated by summing the elevation head, frictional losses, and dynamic losses associated with the piping. The frictional Crescent City Recycled Water Feasibility Study (RWFS) Page 88 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx losses were calculated using the Hazen-Williams equation9 using a coefficient, C, of 150. Minor losses were assumed to be 5% of the frictional losses. The size of the pumps at the treatment systems were calculated using average day irrigation demand flows. The size of the pumps at the storage tanks were calculated using peak hourly demand flows. The calculated motor horsepower for the pumps was rounded up to the nearest compatible motor size. Table 7-5 below summarizes pump design criteria.
Table 7-5. Pump Design Criteria
Project
Alternative 1
Project
Alternative 2
Project
Alternative 3
Design Criteria for Pumps to Storage Tanks
Pump Efficiency 80% 80% 80%
Conveyance Pipe Roughness
(C Factor) 150 150 150
Minor Pipeline Losses (as a
percentage of calculated frictional
losses)
5% 5% 5%
Design Flow (Average Day Demand)
(GPM) 39 42 7
Design Criteria for Pumps to Park Irrigation Systems
Pump Efficiency 80% 80% 80%
Conveyance Pipe Roughness
(C Factor) 150 150 150
Minor Pipeline Losses (as a
percentage of calculated frictional
losses)
5% 5% 5%
Min Irrigation System Pressure (psi) 60 60 60
Design Flow (Peak Hourly Demand)
(GPM)
177 177 33
7.2.3.5 Site Irrigation Facilities
The condition of existing irrigation systems at Beach Front Park and Peterson Park are unknown or not installed. Irrigation system design will need to be verified during detailed design.
7.3 Cost Estimate Approach
The engineer’s opinion of probable construction cost is based on a conceptual level Class 4 estimate, based on AACE Cost Estimate Classification, with -30% to +50% accuracy of the capital and operating costs for each alternative considered for the study (AACE, 2005). Class estimates are shown in Table 7-6. The project costs estimates are presented in Section 8 of this 9 Hazen-Williams formula for frictional loss in a pipeline:
𝐻𝐻𝑓𝑓 = 3.022 1.85𝐿𝐿
𝐶𝐶1.85𝐷𝐷1.165
Where is the velocity (in feet per second), L is the pipeline length (in feet), C is the Hazen-Williams coefficient, and D is the pipeline diameter (in feet).
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Table 7-6. AACE Cost Estimate Classification
Source: ACCE International, 2005.
7.3.1 Capital Costs Approach and Assumptions
Unit capital costs from RS Means Online data and recent relevant projects were used to estimate costs for treatment, conveyance pipelines, pumps, storage tanks, and irrigation systems (RSMeans, 2022). Additionally, costs for site development, miscellaneous piping, electrical, and instrumentation and controls were estimated as a percentage of the total infrastructure costs. Sales taxes, mobilizations costs, contractor overhead and profit costs and an estimate contingency were also applied to all alternatives. Annual escalation was applied to the mid-point of construction, assuming construction were to occur from 2024 to 2026. Total project capital costs were converted to annualized capital lifecycle costs for each project based on 3% discount rates and a 30-year life expectancy for project facilities. Total capital annualized costs were divided by the recycled water delivered for the project to derive a unit cost of Crescent City Recycled Water Feasibility Study (RWFS) Page 90 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx recycled water in dollars per acre-foot ($/AF). Table 7-7 summarizes the cost sources and assumptions used.
Table 7-7. Summary of Capital Costs Approach and Assumptions Capital Cost Description Cost Source/Assumption
Treatment Costs:
Costs estimated based on expected recycled water production volume. Costs were based on RS Means Online Data and unit costs from recent relevant Kennedy Jenks Projects
Conveyance Pipes:
Costs ($/LF) based on a unit cost for each pipe size and include material and labor for pipe segment. Unit prices based on RS Means Online Data and recent relevant projects
Pumps:
Costs estimated based on brake horsepower requirements.
Costs were based on RS Means Online Data and recent relevant projects
Storage Tanks: Costs estimated based on volume of storage using RS Means Online Data and recent relevant projects
Irrigation Retrofit:
Costs estimated based on acreage of irrigated area. Unit costs are based on recent relevant projects and include cross connection testing
Other Site Costs (site,
miscellaneous piping,
electrical, instrumentation):
20% of treatment, pump, and storage facility costs
Other, Markups,
Contingency Costs (taxes,
mobilization, bonds,
permits, contractor
overhead & profit, estimated
contingency):
Taxes – 8.75% applied to 40% of Facility Costs
Mobilization/Bonds/Permits – 5% of Facility Costs
Contractor Overhead & Permit – 15% of Facility Costs
Estimated Contingency – 30% of Facility Costs
Total Project Capital Cost:
Sum of all facility costs, other site costs, markups, and contingency costs including escalation to midpoint of
construction (2% over 2 years, 2024 to 2026)
Annualized Project Capital
Cost:
Total Project Capital Costs converted to an annualized capital cost using 3% discount rate and 30-year life expectancy10
7.3.2 Operation & Maintenance Cost Approach and Assumptions Operation and maintenance (O&M) costs are primarily associated with the treatment systems and include energy costs and maintenance costs. O&M costs do not include park maintenance costs such as mowing, garden planting, or other park upkeep related activities. These costs would need to be considered by the City before project implementation. Table 7-8 summarized the following O&M costs assumptions.
10 Annualized Capital Cost Formula:
𝐶𝐶 𝐶𝐶 𝐶𝐶 𝐶𝐶 × (𝑖𝑖 × (𝑖𝑖 + 1)𝑛𝑛)
(1 + 𝑖𝑖)𝑛𝑛 − 1
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O&M Cost Description Cost Source/Assumption
Energy Use – Treatment (UV
System):
0.24 $/KWh for 150 days of irrigation a year
Energy Use – Pumps: 0.24 $/KWh for 150 days of irrigation a year Energy Use – Other: 5% of Pump Energy Use
Non-treatment Maintenance Costs: 1% of facility costs excluding treatment Contingency: Estimated Contingency – 10% of the subtotal O&M costs
7.3.3 Potable Water Costs Approach and Assumptions
To compare the cost of recycled water to that of potable water, the cost of supplying each alternative with potable water to meet irrigation demands was also calculated. As previously discussed in Section 3.4, water fees in Crescent City have a flat fee of $22.49 for water usage up to 500 cubic feet (cf) per month. For every 100 cf above the 500 cf limit, an additional charge of $2.62 is imposed per month.
Irrigation demands for each park were calculated in cubic feet per month using the average day irrigation demands presented in Table 7-1 and 150 days of irrigation in a year. Using the City’s current potable water rate and the range of rate increases, unit costs to meet irrigation demand with potable water for each alternative were calculated in dollar per acre foot. Calculated potable water costs for each project alternative are presented in Section 8 and are used to compare the cost of supplying recycled water versus potable water for irrigation for each alternative and to evaluate cost effectiveness for each alternative.
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8.1 Alternative 1 – Irrigation of Beach Front Park
Project Alternative 1 consists of producing tertiary treated and disinfected recycled water at the City’s WWTF and conveying it to Beach Front Park for irrigation. Recycled water produced at the treatment plant would be pumped to a storage tank at Beach Front Park, and then delivered to the park irrigation system.
8.1.1 Description of Proposed Facilities
Key facilities and components are summarized in Table 8-1 below. Figure 8-1 shows the approximate pipeline alignments, location of storage facilities, and irrigated areas. A detailed description of each the proposed facilities is included in the following subsections.
Table 8-1. Alternative 1 – Facility Summary
Facility Purpose/Description
Treatment:
2 Pumps (0.5 hp) MBR Reuse Replacement pumps
1 UV Reactor UV reactor replacement
1 Flow Meter Replacement flow meter
Conveyance:
150 LF 4-in pipeline RW conveyance line from 12” RW stubout to storage tank at Beach Front Park
2,000 LF 4-in pipeline RW conveyance line from storage tank to Front St Storage:
60,000-gal storage
tank
Recycled water storage at Beach Front Park
1 Pump (15 hp) Pump to convey RW through RW conveyance
main and into irrigation systems
150 LF 12-inch tank
drain pipe
Tank overflow and drain piping to nearest City
sewer manhole
Irrigation:
Irrigation system at
park
Details on this system are unknown/not included
and will need to be evaluated during final design.
8.1.1.1 Treatment Facilities
The two existing 25-hp, 0.60 MGD MBR reuse pumps in the MBR building basement are oversized for the expected demand this project alternative would service. These pumps would be replaced with new 0.5-hp pumps to convey the recycled water to the storage tank at Beach Front Park. The existing flow meter located on the discharge line of the MBR reuse pumps would be replaced with a more adequately sized flowmeter. The exact flowmeter model would be selected during final design.
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2.0 MGD, which is also oversized for the expected demand this project alternative would service. The two existing UV reactors would be replaced with one UV reactor sized for average day irrigation demands. It is common practice for two UV reactors to be installed for redundancy, however, irrigation only occurs 150 days of the year and is not considered an essential use so only one UV reactor was proposed. If the UV reactor shuts down, the recycled water system will be turned off and the City can decide to either not irrigate the park until the UV reactor is repaired or replaced, or to irrigate the park with potable water. At this time, it is assumed that no piping associated with the UV disinfection system (such as suction or discharge piping) would be replaced for this alternative. An evaluation of the UV system piping would be done in final design.
8.1.1.2 Storage and Conveyance Facilities
Recycled water produced at the WWTF would be conveyed to a proposed storage tank for storage. As described in Section 5, an existing 12-inch recycled water line is capped on the outside of the City WWTF fence near Howe Drive. To convey recycled water from the WWTF to the storage tank, a 4-inch recycled water will connect to the existing 12-inch recycled water line and route to the proposed storage tank, as shown on Figure 8-1. The exact location and condition of the existing 12-inch would be evaluated during final design. The Beach Front Park storage tank is proposed to be at the southwestern corner of the park. This location was chosen based on the availability of open space and proximity to the WWTF but may be updated during detailed design. The storage tank will be a 60,000-gallon tank with a potential footprint up to 40 feet in diameter. The exact storage tank height, diameter, and material would be determined during design. A tank overflow drain would discharge via gravity into the nearest City sewer system manhole, allowing recycled water to be circled back through the WWTF in the case of an overflow condition at the storage tank. The nearest sewer manhole, using the City’s sewer system GIS data and google earth, is located on Howe Drive in the middle of the street as shown on Figure 8-1. The figure shows the potential alignment of the tank drain piping to this existing manhole. At the storage tank, a 15-hp pump is recommended to convey recycled water through a 4-inch pressurized recycled water distribution main and through the park irrigation system. Only one pump is recommended, with no standby pump, for the same reasons only one UV reactor is proposed, as described in the previous section. The proposed 4-inch recycled water distribution main from the storage tank would be installed through the center of Beach Front Park, as previously proposed in the City’s 2010 Engineering Report on Production and Use of Reclaimed Water. This distribution main would be capped at the corner of Front Street and Play Street. The park’s irrigation system would branch off this recycled water main and into the irrigated areas of the park.
BEACH FRONT PARK IRRIGATION AREAS
TOTAL AREA: ~33 ACRES
AVG. DAY IRRIGATION DEMAND: 56,000 GPD
PEAK DAY IRRIGATION DEMAND: 85,000 GPD
CAP RECYCLED WATER DISTRIBUTION
MAIN FOR FUTURE
CONNECTION
~2,000 LF 4" RECYCLED WATER
DISTRIBUTION MAIN
60,000-GAL
STORAGE TANK
AND 15-HP PUMP
~150 LF 4" RW
DISTRIBUTION MAIN
(2) 0.5-HP MBR REUSE REPLACEMENT
PUMPS IN MBR BLDG BASEMENT
CONNECT TO EXISTING
12" RECYCLED WATER LINE
~150 LF TANK OVERFLOW/DRAIN
PIPE CONNECTING TO
EXISTING SEWER MANHOLE
0 100 200
Scale: Feet
City of Crescent City
Crescent City, CA
Alternative 1:
Irrigation of Beach Front Park
K/J 2076056*00
August 2022
Figure 8-1
Z:\Projects\CityOfCrescentCity\Events\20211013_RWFS\Fig8-1_Alternatives1_beachfront.mxd Date: 8/10/2022 Printed by: MaryEllenMcCarty Source: Esri, Maxar, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community Legend
Proposed 4" Recycled Water Distribution Main
Existing 12" Recycled Water Line
Tank Overflow / Drain Pipe
Irrigated Area Footprint
Existing Sewer Manhole
Storage Tank Location
Abbreviations:
BLDG = Building
GPD = Gallons per Day
HP = Horsepower
LF = Linear Feet
MBR = Membrane Bioreactor
Note:
All existing and proposed pipeline alignments are approximate and would need to be finalized during design.
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8.1.2 Cost Estimate
A summary of capital and O&M costs for Alternative 1 are shown in Table 8-2. A detailed cost estimate can be found in Appendix D.
Table 8-2. Alternative 1 – Summary of Probable Costs
Facility Component Estimated Cost
Treatment $46,000
Pipeline $131,000
Pump $12,000
Storage $25,000
Irrigation Retrofit $132,000
Other Site Costs $16,600
Other, Markups,
Contingencies $188,790
Total Capital $573,000
Total Annual O&M $25,530
Annualized Unit Capital
Cost ($/AF) $1,100
Annualized Unit O&M
Cost ($/AF) $900
Annualized Total Unit
Cost ($/AF) $2,000
8.2 Alternative 2 – Irrigation of Beach Front Park + Truck Fill Station
Project Alternative 2 is the same as Project Alternative 1 with the addition of a truck fill station to supply recycled water directly to trucks for potential dust control, local homeowner irrigation, agricultural, or other construction uses.
8.2.1 Description of Proposed Facilities
The same treatment upgrades, conveyance, and storage facilities in Project Alternative 1 would apply to Project Alternative 2. In addition to these facilities, a truck fill station would be installed at the City WWTF.
Per conversations with City staff, the truck fill station would be located within the City WWTF fence. The proposed location of the truck fill station would be in the open space area east of the existing RBCs near the Howe Gate Drive access gate, as shown on Figure 8-2. It was assumed that there would be adequate space in this area to install the fill station facilities, which include steel bollards, a concrete pad, and above grade connection piping and valves. Parking spaces were not proposed for the truck fill station because it was assumed there is enough space within Crescent City Recycled Water Feasibility Study (RWFS) Page 96 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx the access drive to access the fill station. In addition, there is reduced traffic at the Howe Drive gate, per conversations with City staff, so no parking spaces are required.
As mentioned in Section 4.1.2 of this report, an existing above-ground purple recycled water recirculation pipe runs parallel to the access drive, as shown on Figure 8-2. Piping to the fill station would tee into this existing exposed recycled water recirculation pipe, route across the paved access drive below grade to the fill station pad east of the RBCs. The proposed piping and appurtenances to the fill station are 4-inch in diameter; this size would be verified during detailed design.
MBR/UV SYSTEM BLDG
4" RECYCLED WATER
LINE TO STORAGE
TANK AT BEACH
FRONT PARK
CONNECTION TO
EXISTING 12" RECYLED
WATER LINE
PROPOSED TRUCK
FILL STATION
LOCATION
Z:\Projects\CityOfCrescentCity\Events\20211013_RWFS\Fig8-2_Alternatives2_beachfront.mxd Date: 8/10/2022 Printed by: MaryEllenMcCarty Legend Truck Access Routes
Tank Overflow / Drain Pipe
Proposed 4" Recycled Water
Line
Existing 12" Recycled Water
Recirculation Line
Existing Sewer Manhole
Source: Esri, Maxar, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community 0 50 100
Scale: Feet
City of Crescent City
Crescent City, CA
K/J 2076056*00
August 2022
Alternative 2:
Irrigation of Beach Front Park
& Truck Fill Station
Figure 8-2
Abbreviations:
BLDG = Building
GPD = Gallons per Day
HP = Horsepower
LF = Linear Feet
MBR = Membrane Bioreactor
Note:
All existing and proposed pipeline alignments are approximate and would need to be finalized during design.
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8.2.2 Cost Estimate
A summary of Alternative 2 capital and O&M costs are shown in Table 8-3. A detailed cost estimate can be found in Appendix D. The estimated costs vary from Alternative 1 due to the additional required infrastructure for the truck fill station.
Table 8-3. Alternative 2 – Summary of Probable Costs
Facility Component Estimated Cost
Treatment $49,000
Pipeline $131,000
Pump $12,000
Storage $25,000
Irrigation Retrofit $132,000
Fill Station $14,000
Other Site Costs $20,000
Other, Markups,
Contingencies
$199,585
Total Capital $606,000
Total Annual O&M $23,530
Annualized Unit Capital
Cost ($/AF) $1,100
Annualized Unit O&M
Cost ($/AF) $840
Annualized Total Unit
Cost ($/AF) $1,940
8.3 Alternative 3 – Irrigation of Peterson Park
Project Alternative 3 consists of using Rumiano’s UV/RO effluent for irrigation at Peterson Park.
Effluent water would be conveyed to a storage tank at Peterson Park, and then delivered to the park irrigation system.
8.3.1 Description of Proposed Facilities
Key facilities and components are summarized in Table 8-4 below. Figure 8-3 shows the approximate pipeline alignments, location of storage facilities, and irrigated areas. A detailed description of each the proposed facilities are described in the following subsections.
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Facility Purpose/Description
Treatment: Assumed that the effluent produced does not need further treatment to meet Title 22 requirements.
Conveyance:
1,000-LF 2-in pipe RW conveyance line from Rumiano to storage tank at Peterson Park
500-LF 4-in pipe RW conveyance line from storage tank through Peterson Park
1 Pump (0.5 hp) Pump to convey RW from Rumiano Treatment System to storage tank at Peterson Park
Storage:
10,000-gal storage
tank
Recycled water storage at Peterson Park
1 Pump (2 hp) Pump to convey RW from storage tank to irrigation systems
70-LF 6-inch tank drain Tank overflow and drain piping to nearest City sewer manhole
Irrigation:
Irrigation system at
park
Details on this system are unknown/not included
and will need to be evaluated during final design
8.3.1.1 Treatment Facilities
It was assumed for the purpose of this RWFS that no upgrades are necessary for Rumiano’ s industrial wastewater treatment system to further treat its effluent for irrigation use. Further analysis would be required during design if this project were to be implemented.
8.3.1.2 Storage and Conveyance Facilities
To convey industrial effluent to the storage tank at Peterson Park, it was assumed at pump would need to be installed at Rumiano’ s treatment system. This pump was sized to be 0.5-hp. It is common practice for two pumps to be installed for redundance, with one pump as the “duty” pump and the other pump on standby. However, for this project alternative, only one pump is recommended since irrigation only occurs for 150 days of the year and is not supplying an essential use. If the pump shuts down, the recycled water system would be turned off and the City can decide to not irrigate the park until the pump is replaced or irrigate the park with potable water. The location of the pump within Rumiano’ s facility would be determined during final design.
The 0.5-hp pump would convey industrial effluent through a 2” recycled water pipe to a 10,000-gallon storage tank at Peterson Park. This pipeline would be installed within the right-ofway of 9th St and D Street, as shown on Figure 8-3. The proposed storage tank location at Peterson Park is an open space area south of the community gardens, as shown on Figure 8-3.
The exact storage tank height, diameter, and material would be determined during final design.
A tank overflow drain would discharge via gravity into the nearest City sewer system manhole, allowing recycled water to be circled back through the CCWTF in the case of an overflow Crescent City Recycled Water Feasibility Study (RWFS) Page 100 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx condition at the storage tank. The nearest sewer manhole, using the City’s sewer system GIS data and google earth, is located near the intersection of D Street and 6th Street as shown on Figure 8-3. The figure shows the potential alignment of the tank drain piping to this existing manhole. At the storage tank, a 2-hp pump is proposed to convey effluent from the storage tank through 500-feet of 4-inch recycled water distribution main. The park’s irrigation system would branch off this recycled water main and into the irrigated areas of the park.
RUMIANO CHEESE CO
(1) 0.5-HP RECYCLED WATER PUMP AT
RUMIANO TREATMENT FACILITY
~1,000 LF 2" RECYCLED WATER
DISTRIBUTION MAIN
10,000-GAL STORAGE TANK AND
(1) 2-HP PUMP
~500 LF 4" RECYCLED WATER
DISTRIBUTION MAIN
PETERSON PARK IRRIGATION AREA: ~6 ACRES
AVERAGE DAY IRRIGATION DEMAND: 10,000 GPD
PEAK DAY IRRIGATION DEMAND: 16,000 GPD
~70 LF 6" TANK
OVERFLOW / DRAIN PIPE
CONNECTING TO EXISTING
SEWER MANHOLE
Z:\Projects\CityOfCrescentCity\Events\20211013_RWFS\Fig8-3_Alternatives3_PetersonPark.mxd Date: 8/10/2022 Printed by: MaryEllenMcCarty Legend Proposed 6" Tank Overflow /
Drain Pipe
Proposed 2" and 4" Recycled
Water Distribution Main
Irrigated Area Footprint
Existing Sewer Manhole
Storage Tank Location
Source: Esri, Maxar, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community 0 100 200
Scale: Feet
City of Crescent City
Crescent City, CA
K/J 2076056*00
August 2022
Alternative 3:
Irrigation of Peterson Park
Figure 8-3
Abbreviations:
BLDG = Building
GPD = Gallons per Day
HP = Horsepower
LF = Linear Feet
MBR = Membrane Bioreactor
Note:
All proposed pipeline alignments are approximate and
would need to be finalized during design.
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8.3.2 Cost Estimate
A summary of Alternative 3 capital and O&M costs are shown in Table 8-5 below. A detailed cost estimate can be found in Appendix D.
Table 8-5. Alternative 3 – Summary of Probable Costs
Facility Component Estimated Cost
Treatment $0
Pipeline $70,000
Pump $3,300
Storage $10,000
Irrigation Retrofit $29,600
Other Site Costs $2,660
Other, Markups,
Contingencies
$60,696
Total Capital $183,000
Total Annual O&M $3,410
Annualized Unit Capital
Cost ($/AF)
$1,900
Annualized Unit O&M
Cost ($/AF)
$700
Annualized Total Unit
Cost ($/AF)
$2,600
8.4 No Project Alternative
A final project alternative that can be considered is no alternative at all; the City could continue to serve the identified potential recycled water customers with potable water. To analyze this alternative, the annualized total potable water cost to supply the volume of water for each alternative was calculated, as detailed in Section 7.3.3. The comparison of the annualized total recycled water unit cost to the annualized total potable water cost is included in Table 8-6 below. As shown in the table, the annualized total potable water unit cost is approximately half of the annualized total recycled water unit cost for each alternative, indicating that continuing to supply the irrigation demands for these customers with potable water is the most financially feasible decision for the City.
Table 8-6. Comparison of Recycled Water Unit Cost to Potable Water Unit Cost for Each Alternative
Alternative
1 – Beach Front
Park
2 – Beach Front
Park + Fill Station 3 – Peterson Park
Annualized Total
Recycled Water Unit
Cost ($/AF)
$2,000 $1,940 $2,600
Annualized Total Potable
Water Unit Cost ($/AF) $1,144 $1,128 $1,060
Crescent City Recycled Water Feasibility Study (RWFS) Page 103 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx Although the annual costs presented above indicate it is more financially feasible to continue using potable water for irrigation, recycled water may be more cost effective in the future if annual rates of potable and recycled water increase. An analysis was completed to determine when it would be more cost effective to use recycled water for irrigation over potable water using assumed cost rate increases. Recycled water rates typically increase at a rate of 2% annually, while a potential increase of 2-6% per year was considered for current potable water rates to project future rates, based on input from City staff. In addition to the 2% rate increase for recycled water costs, a 6% rate increase was also considered to allocate funding for future potential equipment replacement as infrastructure ages. The analysis was conducted for Project Alternative 1 – Irrigation of Beach Front Park and results are depicted in graphical format in Figure 8-4. The results of this analysis were used as a basis evaluation for all recycled water use in Crescent City.
The pink line on Figure 8-4 shows the annual projection of the project recycled water total costs (capital and O&M) in $/100 cf, with an industry standard 2% annual rate increase. The red line on the graph shows the annual projection of the project recycled water total costs with an annual rate increase of 6%. The yellow, green, and orange lines on the graph show the annual projection of the potable water costs in $/100 cf at 3%, 4.5%, and 6% annual rate increases, respectively. The intersection of the potable water costs and recycled water costs indicate when recycled water would become more economically feasible than potable water for meeting the irrigation demands.
As shown on Figure 8-4, if Crescent City potable water rates increase at a rate of 3% or less (yellow line), the intersection with the recycled water total costs does not occur until beyond 2053, therefore recycled water would be more expensive than potable water until after this year.
If potable water rates increased at a rate of 4.5% (green line), recycled water would be more expensive than potable water until around 2045. If potable water rates increased at a rate of 6% (orange line), recycled water would be more expensive than potable water a little earlier in around 2036. The rates considered for this analysis are estimated based on discussions with the City and the year when potable water becomes more expensive than recycled water is dependent on these rates. If recycled water costs have an annual rate increase of less than 2%, or if potable water rates increase at annual rates larger than 6%, the point at which potable water becomes more expensive than recycled water would occur sooner. If the opposite occurs, the year when potable water becomes more expensive than recycled water would be delayed further into the future. If the City wanted to allocate funding for future equipment replacement using a 6% recycled water rate increase as a funding source, recycled water would be much more expensive than using potable water. Future analysis of funding and costs for equipment replacement would need to be evaluated further to confirm a 6% recycled water rate increase.
If the City could fund all capital costs using grants and only be responsible for O&M costs, the implementation of the recycled water project alternative becomes much more feasible, as the costs of O&M are cheaper than the potable water costs, as shown by the dark red line projection, as shown on Figure 8-5.
Figure 8-4. Beach Front Park Irrigation Total RW vs PW Cost - Current and Projected Trends
2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 0 500
1000
1500
2000
2500
3000
3500
4000
0 5
10 15
20 25
30 $/AF
S/CCF
PW Estimate ($/AF) RW O&M Estimate - 2% ($/AF) RW Cap Estimate - 2% ($/AF) PW Estimate - 6% ($/CCF) PW Estimate - 3% ($/CCF) RW Total Estimate - 2% ($/CCF)) PW Estimate - 4.5% ($/CCF) RW O&M Estimate - 2% ($/CCF) RW Total Estimate - 6% ($/CCF) PW Projected Rates
(max assumes 6%
annual increase)
Beach Front Park Irrigation Total RW vs
PW Cost (Total and Projected Trends) Figure 8-4
K/J 2076056*00
September 2022
Figure 8-5. Beach Front Park Irrigation RW (O&M Only) vs. PW Cost - Current and Projected Trends -
20222023202420252026202720282029203020312032203320342035203620372038203920402041204220432044204520462047204820492050205120522053 $-
$200
$400
$600
$800
$1,000
$1,200
$1,400
$1,600
$1,800
$-
$2.00
$4.00
$6.00
$8.00
$10.00
$12.00
$14.00
$16.00
$18.00
$/AF
S/CCF
PW Estimate ($/AF) RW O&M Estimate - 2% ($/AF) PW Estimate - 6% ($/CCF) PW Estimate - 3% ($/CCF) PW Estimate - 4.5% ($/CCF) RW O&M Estimate - 2% ($/CCF) PW Projected Rates
(max assumes 6%
annual increase)
Beach Front Park Irrigation RW (O&M Only) vs.
PW Cost (Current and Projected Trends)
Figure 8-5
K/J 2076056*00
September 2022
Crescent City Recycled Water Feasibility Study (RWFS) Page 106 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx Section 9 Project Alternatives Analysis
The project alternatives analysis approach consists of scoring and ranking each project based on qualitative and quantitative screening criteria. The following sections provide the basis of the screening criteria and weighting, and the outcomes of the scoring and ranking evaluation used to identify a preferred list of prioritized projects. The analysis and screening criteria were presented to the City of Crescent City at a virtual workshop on July 18, 2022. Feedback received during the workshop was incorporated into the evaluation of each project alternative and adjustments made to the screening criteria.
9.1 Alternatives Screening Approach
This section describes the alternatives screening approach, with a focus on the alternatives screening criteria and weighting themes developed to evaluate each project alternative.
9.1.1 Screening Criteria
For this study, two general categories were used to compare project alternatives against one another:
1) Engineering & Operational Considerations
2) Economic Considerations.
Each category was further broken down into screening criteria and considerations summarized in Table 9-1.
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Alternatives Screening
Criteria Considerations for Assessing Project
Engineering &
Operational
Considerations
Availability of Recycled Water Is there sufficient volume of recycled water produced to supply the demands?
Infrastructure Requirements What infrastructure is required to implement the alternative?
Administrative Complexity
Is coordination with agencies necessary?
Are there permitting requirements?
Will the alternative result in an impact to
operations for the City due to a decrease in
volume sent to WWTF?
Economic
Considerations
Cost Effectiveness What is the cost of using recycled water to meet demand versus potable water?
Capital and Operations &
Maintenance Costs
What is the total capital cost?
What is the annual O&M cost?
What is the annualized unit cost (Capital and
O&M costs per volume of recycled water
produced)?
Funding & Financing Are there any opportunities for obtaining funding for implementation of the alternative?
Each screening criteria shown in Table 9-1 was evaluated for each project alternative based on a three-step process (scoring, weighting, and ranking) described as follows. Scoring and weighting are described in more detail in the following sections.
1. Scoring: Each alternative was initially scored based on scoring guidelines.
2. Weighting: Weighting factors were developed to reflect the relative importance of each criterion.
3. Ranking: Each alternative project was then ranked based on the total scoring and weighting of each alternative.
9.1.2 Raw Scoring
Alternative projects were scored on a scale of one to three for each screening criterion, where:
Score = 3 Fully Meets Criteria
Score = 2 Generally Meets Criteria
Score = 1 Unable to Meet Criteria
Guidance for scoring each screening criterion was established with input from the City. This guidance included quantitative and qualitative metrics, depending on the nature of the screening criterion. Some screening criteria have several guidance considerations, such as Administrative Crescent City Recycled Water Feasibility Study (RWFS) Page 108 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx Complexity, which includes consideration of coordination with outside agencies, the complexity of the permitting pathway, and the impact to current operations. A guidance for scoring each metric is summarized in Table 9-2 and described in the following sub-sections.
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Guidance for Scoring
Fully Meets Criteria Meets Criteria Unable to Meet Criteria Alternatives
Screening
Criteria
3 2 1
Availability of
Recycled
Water
There is sufficient
volume of recycled
water to meet peak
demands during all
months where demand
exists.
There is enough
recycled water to meet
peak demands during
at least 50% of the
months where demand
exists.
There is recycled water
available to meet peak
demands for less than 50% of
the months where demand
exists.
Infrastructure
Requirements
No additional
infrastructure or
improvements to
existing infrastructure
required.
The alternative calls
for opportunities to
utilize or minimally
improve existing
infrastructure.
The alternative requires
significant improvement of
existing infrastructure or
installation of new
infrastructure.
Administrative
Complexity
No coordination with
outside agencies or
entities required.
Coordination with one
outside agency or
entity required.
Coordination with more than
one outside agency or entity
required.
Simple permitting
pathway.
Moderate permitting
pathway. Complex permitting pathway.
Low impact to current
operations.
Moderate impact to
current operations.
High impact to current
operations.
Cost
Effectiveness
The cost of using
recycled water to meet
demand is less than
the cost of using
potable water.
The cost of using
recycled water to meet
demand is comparable
to the cost of using
potable water.
The cost of using recycled
water to meet demand is
considerably more than the
cost of using potable water.
Capital and
Operations
and
Maintenance
Costs
Relative to other
alternatives, the total
capital cost is low.
Relative to other
alternatives, the total
capital cost is
comparable.
Relative to other alternatives,
the total capital cost is high.
Relative to other
alternatives O&M
costs, the total O&M
cost is low.
Relative to other
alternatives O&M
costs, the total O&M
cost is comparable.
Relative to other alternatives
O&M costs, the total O&M cost
is high.
Relative to other
alternatives, the
annualized unit cost is
low.
Relative to other
alternatives, the
annualized unit cost is
comparable.
Relative to other alternatives,
the annualized unit cost is high.
Funding and
Financing
There are numerous
funding opportunities
available and a high
likelihood of receiving
funding.
There are funding
opportunities available.
The likelihood of
receiving funding is
moderate.
There are limited funding
opportunities available. There
is low likelihood of receiving
funding.
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9.1.2.1 Engineering and Operational Considerations
Scores were based on the amount of recycled water available to meet demands, infrastructure required for implementation, and administrative complexity (coordination with outside agencies, permitting pathway complexity, and impact to current operations).
Projects received a score of 3 for the availability of recycled water if the recycled water produced exceeded the demand of recycled water for that alternative. Due to the design of the alternatives and the sizing of the facilities using average day irrigation demand, each alternative received a score of 3.
Infrastructure requirements were evaluated based on the length of pipeline, the number of irrigation sites, the number of fill stations, the storage tank size, and the pump size that would be implemented for each project alternative. A quantitative score of 1-3 was determined for each of these sub-criteria, and then averaged to determine a final quantitative score for the infrastructure requirements criterion. For the length of pipeline sub-criterion, scores were calculated by assigning the alternative with the shortest length of pipeline a 3, the longest length of pipeline a 1, and any pipeline lengths between the shortest and the longest a linearly scaled value between 1 and 3 based on the length. Similar calculations were completed for all other sub-criteria, using the number of sites, storage tank sizes, or pump sizes for the calculation.
Agency coordination and permitting were scored based on anticipated agency coordination and permitting requirements, previous projects, and discussions with City staff. Projects with no predicted agency coordination received a score of 3, while coordination with more than two agencies received a score of 1. Permitting pathways anticipated to be simple were given a score of 3, while complex permitting pathways were given a score of 1. Based on discussions with City staff and Kennedy Jenks experience, each alternative was given a score of 2 for permitting pathways. Anticipated permitting pathway information is included in Section 10.
Impact to City operations were scored based on predicted impact to City sewer system or WWTF operations for recycled water production. Based on discussions with City staff, each alternative was given a score of 2 for the impact to City operations criteria.
9.1.2.2 Economic Considerations
Scores were based on cost effectiveness, capital, O&M, and the expected availability of funding and financing for each alternative.
Cost effectiveness scores were calculated by assigning the alternative with the smallest ratio of annualized recycled water total cost to the total potable water cost a 3, the greatest ratio a 1, and any ratio between the largest and smallest a linearly scaled value between 1 and 3 based on the ratio.
Capital, O&M, and annualized costs were calculated for each project alternative, as described in Section 8. A quantitative score of 1-3 was determined for each of these sub-criteria, and then averaged to determine a final quantitative score for the capital and O&M costs criterion. Scores were calculated by assigning the alternative with the highest cost a score of 1 (since higher cost is less desired), the lowest cost a score of 3, and any cost between the highest and the lowest a linearly scaled value between 1 and 3 based on the cost.
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9.1.3 Weighting Approach
Project alternatives scores were also weighted based on the relative importance of each screening criteria, resulting in a score on the scale of 1-100. Four different weighting scenarios were developed to assess the sensitivity of the scoring results and determine if different alternatives were preferred under different weighting scenarios. These scenarios include:
(1) Baseline (Balanced) scenario, where each criterion is given a similar weighting percentage; (2) Minimize Administrative Complexity scenario, where the administrative complexity criterion is given the largest weight percentage;
(3) Maximize Engineering and Operational considerations scenario, where the infrastructure requirements, administrative complexity, cost effectiveness, and capital and O&M costs criteria are given larger weights than the other criteria; and
(4) Low Cost scenario, where the capital and O&M costs and funding and financing criteria are given the largest weight percentages.
Weighting for each criterion for each scenario is summarized in Table 9-3.
Table 9-3. Criteria Weighting for Sensitivity Scoring Scenarios Categories
Alternatives
Screening
Criteria
Baseline
(Balanced)
Minimize
Administrative
Complexity
Maximize
Engineering &
Operational
Considerations Low Cost
Engineering &
Operational
Considerations
Availability of
Recycled
Water
15% 10% 10% 5%
Infrastructure
Requirements 15% 10% 25% 5%
Administrative
Complexity 15% 40% 25% 5%
Economic
Cost
Effectiveness 20% 10% 25% 5%
Capital and
Operations &
Maintenance
Costs
20% 10% 20% 30%
Funding &
Financing 15% 20% 5% 25%
Total 100% 100% 100% 100%
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9.2 Project Alternatives Scoring and Ranking Results
The highest raw score (prior to weighting) that a project alternative could receive is 24, based on the screening criteria and considerations for assessing each project. The highest weighted score that a project alternative could receive is a 100. The results of the scoring assessment and the sensitivity scoring analysis are included in Table 9-4 below. A discussion of the scoring and results for each alternative is included below. Details on the assigned score for each scoring criterion for each alternative is included in Appendix E.
Table 9-4. Scoring Results
Weighed Scores
Alternative
Total Raw
Score
Baseline
(Balanced)
Minimize
Administrative
Complexity
Maximize
Engineering &
Operational
Considerations Low Cost
1 – Beach Front
Park 18.0 78 77 69 81
2 – Beach Front
Park & Fill
Station
17.7 76 76 66 82
3 – Peterson
Park 16.9 74 72 71 70
The three alternatives are very similar in raw scores. Project Alternative 1 had the highest total raw score, 18.0 out of the maximum 24, closely followed by Alternative 2 with 17.7. Alternative 2 was also relatively close, with a total raw score of 16.9.
For each of the weighted scenarios, Alternative 1 and Alternative 2 are very similar in scores, with the largest difference occurring for the Maximize Engineering and Operational Considerations scenario (only a 3-point difference). The scoring spread for all three alternatives is narrowest for the Baseline (Balanced) scenario (a spread of only 4 points between the lowest and highest scores). The spread is also close for the Minimize Administrative Complexity and Maximize Engineering & Operational Consideration scenarios (5 point spread). The largest difference between the scores comes for the Low Cost scenario, where the spread is 12 points.
The Low Cost scenario is also the only scenario where Alternative 2 has a higher score than Alternative 1, due to the lower annualized total cost ($/AF) of Alternative 2 compared to Alternative 1.
The results of the scoring and weighting analysis do not indicate a strong recommendation towards one alternative over another. All three project alternatives have similar scores, with Alternative 1 having slightly greater scores across the board than the other two alternatives.
However, these scores indicate that the choice of a recommended project is not obvious and that neither of these three projects may be selected for implementation. Additional public outreach could be considered to determine if there is a preference for one of these alternatives from the community.
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Operation Plan
10.1 Recommended Project
After presenting the alternatives evaluation to the City, it was decided that the scoring and rankings did not give clear indication as to which project alternative would be most beneficial for the City. Based on feedback from the City, the recommended approach was to consider both Project Alternatives 1 and 3 as potential future projects and evaluate the funding availability for construction costs of each.
10.2 Implementation Plan
Implementation Plan details are included in the following sub-sections. Some of the items for consideration are unique to one of the projects, while others are generally the same for each project.
10.2.1 Coordination
Coordination between relevant parties is critical for both project alternatives. Different parties are relevant for each alternative, and details on the important coordination activities are included in the following subsections.
10.2.1.1 Project Alternative 1 - Beach Front Park
Critical coordination items for irrigation at Beach Front Park may include, but are not limited to:
• Identification of each City department’s responsibilities related to recycled water, • Communication between the WWTF and the California Regional Water Quality Board for recycled water permit compliance (see Section 10.2.3)
• Coordination of activities related to design, construction, and operation of facilities at the WWTF
• Establishment of rate structures for recycled water use
10.2.1.2 Project Alternative 3 - Irrigation for Peterson Park Critical coordination items for irrigation at Peterson Park may include, but are not limited to:
• Identification of each City department’s responsibilities related to recycled water, • Communication between Rumiano Cheese Company and the California Regional Water Quality Board for the purpose of recycled water permit compliance (see Section 10.2.3) Crescent City Recycled Water Feasibility Study (RWFS) Page 114 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx • Coordination between Rumiano Cheese Company and the WWTF for reduced discharge flow to plant
• Coordination of activities related to design, construction, and operation of facilities • Establishment of rate structures for recycled water use
10.2.2 Ability and Timing of Users to Join System
For both project alternatives, the critical activities with respect to the ability and timing of users to join the system include recycled water use permitting and the construction of the treatment facility upgrades, conveyance and storage facilities. Once permitting has been completed and these key facilities are constructed, the existing irrigation systems can be retrofitted or constructed to distribute recycled water. Therefore, the ability and timing of users to join the water system are dependent upon permitting and the construction and operation schedule of these key facilities.
10.2.3 Tentative Water Recycling Requirements
10.2.3.1 Project Alternative 1 – Irrigation of Beach Front Park As discussed previously in this report, the Crescent City WWTF currently operates under NPDES Discharge Permit Order #R1-2017-0002 for secondary and tertiary treated wastewater.
For the treatment system upgrades and implementation of the UV system, Crescent City WWTF will need to coordinate with the Regional Water Quality Control Board to make amendments to the current NPDES Permit. In addition to NPDES Permit amendments, the City will need to obtain permit coverage for the use of recycled water prior to initiating recycled water use as stated in Section IV.C.2 of the current NPDES Permit. Recycled water use is covered under the statewide general permit State Water Resources Control Board Order WQ-2016-0068-DDW, Water Reclamation Requirements for Recycled Water Use (General Order), included in Appendix F. To obtain permit coverage under the General Order, a Notice of Intent (NOI) identifying the recycled water producer, distributer, and user needs to be prepared and submitted to the Regional Water Quality Control Board. The City WWTF would be the producer, City Public Works the distributor and user. A water recycling program technical report must also be submitted with the NOI that includes the following information:
• Description of the existing and/or proposed treatment, storage, and transmission facilities for recycled water
• Recycled Water Application, describing how the recycled water will be used, including maps and quantities of use,
• Description of Water Recycling Program, including agency authority, cross-connection testing, monitoring and reporting program, inspection, compliance, training and emergency procedures,
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• Submittal of an approved Title 22 Engineering Report that demonstrates or defines compliance with the Uniform Statewide Recycling Criteria. See Appendix F for Title 22 Engineering Report Guidance.
• If there is a groundwater resource to be protected, a Salt and Nutrient Management Plan might be required by the Regional Water Quality Control Board to address the potential for recycled water use to impact groundwater quality and to promote basin-wide management of salts and nutrients in groundwater.
• Securing Waste Discharge Requirements (WDRs) or NPDES permits for recycled water production facilities
• Completion of applicable CEQA documentation of mitigation measures, and • Updates to local ordinances, as appropriate.
10.2.3.2 Project Alternative 3 – Irrigation of Peterson Park Processing facilities (wine, beverage, food) that plan to discharge their waste effluent to land for the purposes of reuse, such as irrigation, must apply for coverage under the Waste Discharge Requirements (WDRs) Order No. R1-2016-0002 General Waste Discharge Requirements for the Discharges of Wine, Beverage, and Food Processor Waste to Land in the North Coast Region issued by the California Regional Water Quality Control Board, North Coast Region.
Rumiano currently does not operate under this order as they do not currently discharge to land and will need to obtain a Waste Discharge Permit for the purposes of using effluent as irrigation.
Either a General or Individual WDR Permit may be obtained based on the wastewater characteristics. The WDR Order can be found in Appendix F. Requirements to obtain coverage under the order and a Waste Discharge Permit are generally described as follows:
• Complete Application Process for WDR:
Form 200
Technical Information Form (TIF)
• Demonstrate compliance with all applicable provisions of the Water Quality Control Plan for the North Coast Region
• File a Report of Waste Discharge (ROWD), which includes an Antidegradation Analysis • Complete any applicable CEQA documentation
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10.2.4 Commitments from Potential Users
For both project alternatives, the City parks, operated by the Public Works Department, are the potential users of the recycled water treatment systems and have been active participants and stakeholders for this RWFS. For Peterson Park, the City would need to engage with Rumiano to formalize commitments and responsibilities of each party regarding the recycled water production and irrigation of Peterson Park. Throughout the process of preparing this RWFS, contacts and meetings have been made to Rumiano and the City, both of which are receptive to using recycled water generated from Rumiano’s treatment facility and the City WWTF. The City would obtain letters of commitments from Rumiano if Project Alternative 3 is selected.
10.2.5 Water Rights Impact
No water rights impacts are expected since Water Code Section 1210 assigns ownership of the treated wastewater to the owner of the wastewater treatment plant, Crescent City. The secondary effluent is currently discharged to the Pacific Ocean, not to freshwater receiving body, therefore does not impact downstream water rights.
10.2.6 Permits, Right-of-Way, Design, and Construction
As discussed in Section 10.2.3, compliance with the General Order and preparation of a Title 22 Engineering Report, and amendment/updates to existing NPDES permits would be required for the Beach Front Park alternative. The Beach Front Park project alternative is also located in the coastal zone. Proposed development within the coastal zone will require a Coastal Development Permit issued by the California Coastal Commission. A Coastal Development Permit will need to be obtained prior to completion of any applicable CEQA documentation. For the Peterson Park alternative, a WDR permit would need to be obtained.
Infrastructure for the recommended projects do not require new land acquisition or easements.
Proposed pipelines for both projects are located within City public right-of-way possibly requiring encroachment permits during construction. Detailed survey, utility location, and geotechnical information would be obtained prior to design.
10.2.7 Detailed Schedule
Potential schedules for Beach Front Park and Irrigation at Peterson Park are provided in Figure 10-1 and Figure 10-2, respectively. The schedules provide a high-level detail about the duration and sequence of five primary activities to implement recycled water use: 1) Predesign, 2) Permitting, 3) Design, 4) Construction, and 5) Commissioning.
10.2.7.1 Beach Front Park Project Schedule
The predesign of Beach Front Park would be critical to confirm the basic assumptions regarding the project including sizing, treatment upgrades, pipeline alignments, and utility location, which Crescent City Recycled Water Feasibility Study (RWFS) Page 117 \\kjc\kjc-root\kj-office\eug\wp\2020\2076056.00 - stover engrg - crescent city feasibility study for recycled water\09-reports\9.09-reports\cc_rwfs_report_final_01.05.2023.docx can be used to prepare NPDES Permit amendments and submittal documents for the General Order. Predesign would also include coordination to mobilize surveying and geotechnical investigations as they are necessary prior to Final Design.
The critical path for permitting entails coordination with the Regional Water Quality Control Board to receive approval for updates to the existing permits and obtain coverage on the General Order.
The preparation of plans and specifications during the design phase could be divided into three areas of work: 1) treatment upgrades in the Crescent City WWTF, 2) recycled water conveyance pipes and storage tank and 3) installation of new irrigation systems or retrofits. The design would build on pre-design efforts, incorporating any new information obtained during land and utility surveys and the geotechnical investigation.
Construction activities include bid and award for the work and construction of the required facilities. Following construction, the commissioning phase includes testing of the treatment facilities prior to producing recycled water for delivery and cross connection testing at the park.
10.2.7.2 Peterson Park Project Schedule
The predesign of irrigation at Peterson Park would include evaluating the existing treatment system at Rumiano Cheese Company and confirming whether additional treatment systems need to be added to meet non-potable reuse requirements. It is critical to confirm the basic assumptions regarding the project including sizing, treatment upgrades, pipeline alignments, and utility location, which can be used to prepare submittal documents for the WDR. Predesign would also include coordination to mobilize surveying and geotechnical investigations as they are critical to obtain prior to Final Design.
Permitting for this project alternative would involve preparation of a Report of Waste Discharge and obtaining permit coverage through a Waste Discharge Requirements Permit as discussed in Section 10.2.3. Approval of a WDR for this project is one of the critical paths for moving this project forward.
The preparation of plans and specifications during the design phase could be divided into three area of work: 1) applicable treatment upgrades at Rumiano Treatment Facility, 2) recycled water conveyance pipes and storage tank and 3) installation of new irrigation systems or retrofits. The design would build on pre-design efforts, incorporating any new information obtained during land and utility surveys and the geotechnical investigation.
Construction activities include bid and award for the work and construction of the required facilities. Following construction, the commissioning phase includes testing of the treatment facilities prior to producing recycled water for delivery and cross connection testing at the park.
Figure 10-1. Beach Front Park Schedule
Task and Key Activities
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
Predesign
Utility Location, Survey, Geotechnical InvestigationsConfirm Pipeline Alignment and Facility Sizing Assumptions Permitting
RWQCB WWTF NPDES Permit UpdateCoastal Development Permit, CEQA Compliance (Mitigated Negative Declaration assumed)
RWQCB/DDW Permit Requirements for RW Production/Distribution/Use Design
CC WWTF Treatment UpgradesOff-Plant Conveyance Piping and StoragePark Irrigation System and Retrofits Construction
Bid and Award (treatment, distribution, irrigation system)CC WWTF Treatment Upgrades Off-Plant Conveyance Piping and StoragePark Irrigation System and Retrofits Commissioning
UV Disinfection Validation TestingCross Connection TestingStartup Task DurationActivity Duration
LEGEND
2024 2025 2026 2027
P:\Eugene\2020\2076056.00_Stover_Feasibility_Study_for_Recycled_Water\Section_9_Report\9.09_Report\Draft Figures\Fig10-1_10-2_Project Schedules 9/2/2022 Figure 10-2. Peterson Park Schedule
Task and Key Activities/Deliverables
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
Predesign
Utility Location, Survey, Geotechnical InvestigationsConfirm Pipeline Alignment and Facility Sizing Assumptions Permitting
CEQA Compliance (Mitigated Negative Declartion assumed)RWQCB WDR Permit Requirements for RW Production/Distribution/Use Design
Rumiano Treatment UpgradesOff-Plant Conveyance Piping and StoragePark Irrigation System and Retrofits Construction
Bid and Award (treatment, distribution, irrigation system)Rumiano Treatment Upgrades Off-Plant Conveyance Piping and StoragePark Irrigation System and Retrofits Commissioning
TestingCross Connection TestingStartup
Task DurationActivity Duration
LEGEND
2024 2025 2026 2027
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10.3 Operational Plan
A Recycled Water Operations Plan would identify responsible parties, equipment operation and maintenance, monitoring, and irrigation scheduling, as summarized in Table 10-1 below and detailed in the sub-sections that follow.
Table 10-1. Summary of Operational Plan Considerations
Considerations Alternative 1 – Irrigation of Beach
Front Park
Alternative 3 –Irrigation of Peterson
Park
Responsible
Parties
City WWTF Operators & City Public
Works Department
City Public Works Department &
Rumiano Cheese Company
Equipment
Operations &
Maintenance
City WWTF Operators = WWTF
Upgrades
City Public Works Dept = Storage
and Distribution Systems, Irrigation
System
Rumiano = Treatment Plant Upgrades
City Public Works Dept = Storage and
Distribution Systems, Irrigation
System
Monitoring
City WWTF Operators = RW
production, Effluent Quality
City Public Works Dept = Storage
and Distribution System, Irrigation
System
Rumiano = RW production, Effluent
Quality
City Public Works Dept = Storage and
Distribution System, Irrigation System
Irrigation
Scheduling City Public Works Dept City Public Works Dept
10.3.1 Responsible Parties
There are several ways of assigning responsible parties within the current City structure; one where each City department maintains responsibility based on their recycled water roles as producers, distributors, or users, and another where a single City department assumes responsibility for the entire recycled water program. Table 10-1 above suggests roles and responsibilities would be on a department basis.
The City’s contracted WWTF Operators would be responsible for recycled water production at the WWTF. The City Public Works Department would be responsible for storage and distribution of recycled water. The City Public Works Department would also be responsible for operation and maintenance of the irrigation system, manage cross connection testing, and irrigation scheduling. There may be overlap between all departments, therefore activities should be coordinated for efficiency and consistency.
Irrigation of Peterson Park from Rumiano Cheese Company treated effluent would require the roles and responsibilities to be defined by Rumiano and the City prior to implementation.
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10.3.2 Equipment Operations and Maintenance
Table 10-1 suggests equipment O&M responsibilities would be similarly distributed based on roles. For example, WWTF Operators for the Beach Front Park project and Rumiano staff for the Peterson Park project would assume the role of O&M for the facilities at each treatment system to produce recycled water that meets the regulatory requirements. City Public Works would likely be responsible for O&M of the conveyance, storage facilities and irrigation system.
10.3.3 Monitoring
10.3.3.1 Project Alternative 1 – Irrigation of Beach Front Park A Monitoring and Reporting Program for recycled water production, distribution and use as defined in Attachment B of the General Order as found in Appendix F. Requirements include annual priority pollutant and Total Coliform Bacteria and turbidity monitoring for the treatment facility and Use Area Monitoring requirements for irrigation and dual-plumbed systems.
Monitoring information is required to be submitted in an annual report by the recycled water operator. The annual report includes a summary table of all recycled water users and use areas, a summary table of inspections and enforcement activities at use areas, evaluation of performance of the recycled water treatment facility, summary of monitoring data collected as well as the name, contact information and certification of the recycled water operator responsible for operation, maintenance, and system monitoring. Crescent City WWTF operators would work collaboratively with the City to complete monitoring and reporting requirements for this project alternative.
10.3.3.2 Project Alternative 3 – Irrigation of Peterson Park Monitoring and reporting requirements are included as part of the MRP No. R1-2016-0002 for dischargers under a General WDR. Monitoring and reporting requirements may differ for dischargers under an Individual WDR. General WDR monitoring and reporting requirements include processing volume and chemical usage monitoring, and effluent quality analyses for Biochemical Oxygen Demand (BOD), Dissolved Oxygen (DO), pH, Total Dissolved Solids, Ammonia, Nitrite, and Nitrate as detailed in Appendix F. This monitoring information is required to be submitted in semiannual monitoring reports. Additional monitoring and reporting requirements may be required, including groundwater monitoring and land application area reporting. Rumiano Cheese Company would work collaboratively with the City to complete monitoring and reporting requirements for this project alternative.
10.3.4 Recycled Water Delivery Scheduling
Further coordination between City Public Works Department and the City WWTF or Rumiano for recycled water delivery would have to occur to better understand park irrigation needs and timing. For both projects, storage is required at each park to provide irrigation scheduling flexibility and flatten peak demands on the system. Ideally, flows would be conveyed continuously to a storage tank during the day and then serve the parks from the storage tank during the evening hours (typical irrigation hours). Hydraulic modeling may be performed to optimize storage and booster pump sizing to establish a schedule to meet peak flow demands during design.
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11.1 Construction Funding Sources and Considerations
In recent years, agencies across the United State have faced water reliability concerns which have resulted in an increase in agencies evaluating the feasibility of implementing recycled water systems. A large portion of recycled water project costs are the initial costs incurred to construct the system. Funding these significant construction costs is one of the largest obstacles to overcome when implementing a recycled water system. Most often, agencies do not have sufficient reserves set aside to fund recycled water construction costs. However, depending on the type of recycled water system being implemented and the intended use of the water, there may be other funding options available. The following sections briefly describe some of the funding mechanisms the City may consider to finance the recycled water project alternatives detailed in this RWFS.
11.1.1 Grants and Loans
Many State and Federal funding programs have been created to assist agencies with funding recycled water feasibility studies, as well as the design and construction of recycled water projects. The type (e.g. irrigation and industrial uses vs potable reuse) of recycled water project being constructed can determine whether the project is considered a wastewater or a drinking water project. In determining whether to pursue grant and loan funding, the City should consider the following factors:
Grant and loan funding can minimize the impact to rate payers. Low interest loan funding can save a significant amount of interest on capital projects with a 30-year payment term.
Grant funding is highly competitive; low interest loan funding can be comparatively less competitive.
Grants are typically reimbursements, meaning the City must initially fund the entire construction project and wait for reimbursements. This requires sufficient cash flow from the City during construction. Loans and grants may require a substantial (9 months to 1 year) lead time before an agreement is in place and expenses are reimbursed. Fully forgivable loans and grants with no match requirement are available for disadvantaged communities (DAC) whose median household incomes (MHI) or average household incomes (AHI) are less than 80% of the statewide MHI or AHI and severely disadvantaged communities (SDAC) whose MHI or AHI is less than 60% of the statewide MHI or AHI; the City is located in areas designated as SDAC. The availability of low interest loans may vary by fiscal year depending on the amount of capitalization and the priority system of the loan funding agency, therefore timing of the application could be critical.
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If construction bid costs exceed estimates, the budget for a loan can sometimes be expanded to accommodate the increased need for funding, whereas granting agencies would not typically offer more grant money once the award has been announced.
Table 11-1 summarizes some of the potential State and Federal funding mechanisms the City may consider.
Table 11-1. Summary of Potential Grant/Loan Options
Program Funding Mechanism Brief Description
State
SWRCB – Water
Recycling Funding
Program
Grants/Loans Intended to promote the beneficial use of
treated wastewater, programs with available
funding include
Clean Water State Revolving Fund
(CWSRF) Program – Low interest loans
including forgivable loans (i.e. grants) for
DAC, to public agencies for planning, design,
and construction of water recycling projects.
Recent additional federal infrastructure funds
may be available through the SWRCB
CWSRF for recycled water projects.
Limited funding may be available through
Proposition 1 – Grants and low interest
financing for water recycling projects through
Integrated Regional Water Management Plan
(IRWM) program
Proposition 68 – Loans and grants for
recycled water planning and construction
California
Infrastructure and
Economic
Development Bank –
(I-Bank)
Loan Terms Infrastructure State Revolving Fund (ISRF)
Program - Eligible costs for financing of up to
$25 million include, but are not limited to:
1. Construction, renovation, acquisitions
of lands, structures, real or personal
property.
2. Machinery, equipment and financing
charges.
3. Reserves for principal and interest and
for extensions enlargements,
additions, replacement, renovations,
and improvements.
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Federal
US Bureau of
Reclamation – Title
XVI – Water
Reclamation and Reuse
75% Local Cost share Funding is available for the following types of projects:
1. Authorized Projects: design and
construction of congressionally
authorized Title XVI water reclamation
and reuse project. As of December
2016, the WIIN Act allows new water
recycling projects to be eligible for
federal funding.
2. WaterSMART Title XVI Feasibility
Studies: new water reclamation and
reuse study.
3. Research Studies: expand water
reuse markets, improve water
facilities, implement clean water
technology at new facilities.
Office for Coastal
Management – NOAA
Coastal Resiliency
Grants Program
Matching funds Coastal Management programs include
Administrative Grants, Coastal Resource
Improvements Program Grants, and Coastal
Zone Enhancement Program Grants
Due to the small size of the project alternatives presented in this study and the adequate supply of potable water supply in Crescent City, it may be difficult for the City to qualify for the above listed funding programs. However, as mentioned above in Table 11-1, CWSRF offers forgivable loans for DAC/SDAC’s to public agencies for planning, design, and construction of recycled water projects. California’s AHI is approximately $63,783 with 60% being approximately $38,270, categorizing communities to be a SDAC. The City’s 2016-2020 MHI was $33,347 indicating the City a SDAC and was confirmed a small SDAC per conversations with the SWRCB. Therefore, of the above listed programs for grants and loans, the most feasible and opportune program for the City to apply for would be a forgivable loan (a grant) under the CWSRF Program.
11.1.2 Short Term or Long-Term Bonds
Several debt financing options are available to fund recycled water projects such as General Obligation Bonds, Revenue Bonds, and Certificates of Participation. Debt financing is often considered when liquid cash is not sufficient to fund major capital projects. There are several advantages to issuing debt, including mitigating impact to existing customers, proceeding with capital projects despite having insufficient reserves, and achieving intergenerational equity by recovering costs of capital over those that benefit from the system in the future in addition to existing customers. Other considerations regarding short and long-term bonds should be considered. For example, agencies are typically required to meet debt coverage requirements which limits additional debt if significant debt already exists, or agencies must have the necessary taxing capacity to issue the bonds.
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11.1.3 Utility Rates
Utility rates from water, wastewater, or recycled water customers may fund recycled water construction projects on a pay-as-you-go basis or using rate funded reserves. Using utility rates to fund capital projects avoids incurring additional costs such as interest, issuance costs, and administrative costs associated with grants and loans; however, this requires the existing customers to absorb the entire burden of a system for many years.
11.2 Recycled Water Pricing Policy Options
Crescent City currently does not have recycled water rates in place since all water needs are met with potable water. Further discussion within the City would need to occur to establish a recycled water rate structure based on potential recycled water project capital and/or O&M costs.
11.3 Costs That Can Be Allocated to Water Pollution Control There are not likely to be any additional water pollution control costs associated with the two recommended projects.
11.4 Annual Projections
11.4.1 Water Prices for Each User or Category of Users
Annualized unit recycled water prices and potable water prices in dollar per acre foot ($/AF) were determined as discussed in Section 7.3 and can be seen in Section 8 for each project alternative.
As part of the Alternatives Analysis described in Section 9, a cost effectiveness score was given for each alternative based on the ratio of the annualized unit total recycled water project costs (capital and O&M) to the annualized unit total potable water costs if potable water were used to meet irrigation demand. The recycled water costs to implement each project is higher than meeting the demand with potable water due to the cost of the required infrastructure that would need to be constructed. Recycled water is currently not effective based on potable water rates.
Recycled water can become cost effective in the future depending on the annual increase in water rates, as discussed in Section 8.4. For Project Alternative 1 – Irrigation of Beach Front Park, recycled water use becomes more economically feasible between 2036 (for potable water annual rate increase of 6%) and 2053 (for potable water annual rate increase of 3% or less).
11.4.2 Recycled Water Used by Each User
As described in Section 8, the future users of the recycled water produced by the WWTF or Rumiano Cheese Company are irrigation of City parks, specifically Beach Front Park and Peterson Park.
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11.4.3 Annual Costs of Recycling Project
Annual recycled water and potable costs for each recycled water project are described in Section 8.
11.4.4 Allocation of Costs to Users
Both capital and O&M costs will be included in the price that the City pay for recycled water; capital costs may be offset by forgivable loans or grants.
11.4.5 Unit Costs to Serve Each User or Category of Users and Unit Pricing
Until the City has developed pricing objectives, a recommended unit price for recycled water cannot be determined.
11.4.6 Sensitivity Analysis Assuming Portion of Potential Users If the Parks do not use as much recycled water as anticipated, more effluent would be sent to the outfall (in the case of Alternatives 1 and 2) or discharged to the City’s sanitary sewer system and sent to the WWTF (in the case of Alternative 3). This is the current operation for these two flows, therefore there would be no impact to the City’s system if potential users use less recycled water than expected.
11.5 Sunk Costs and Indebtedness
If capital financing needs to be repaid the implementation of these projects, it is likely there could be a significant level of sunk costs and indebtedness for the City, since the funding sources for the two recommended project alternatives is currently unknown. Implementation without a grant or forgivable loan would require a significant amount of money to be absorbed by the City for facility construction and O&M costs.
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(AACE, 2005). Associate for the Advancement of Cost Engineering. Cost Estimate Classification System – As Applied in Engineering, Procurement, and Construction for the Process Industries. February 2 2005.
(Del Norte Economic Plan, 2020). Del Norte County, Crescent City, Crescent City Harbor District. Del Norte County, Comprehensive Economic Development Strategic Plan (DEL NORTE ECONOMIC PLAN, 2020) 2019-2024. February 2020. (Del Norte Hazard Mitigation Plan, 2019). Tetra Tech. Del Norte County, Operational Area Hazard Mitigation Plan. June 2019.
(Facilities Plan, 2003). Brown and Caldwell. Wastewater Facilities Plan for Crescent City.
October 2003.
(New Frontier Data, 2021). New Frontier Data. Cannabis H2O: Water Use & Sustainability in Cultivation. 2021.
(Layne, 2019). Layne. Ranney Collector Evaluation Report. April 16 2019. (NPDES, 2017). North Coast Regional Water Quality Control Board. Order No. R1-2017-0002 NPDES No. CA0022756. February 2017.
(RSMeans, 2022). RSMeans data from Gordian. Version 8.7. Accessed June 2022. (UWMP, 2016). Freshwater Environmental Services. 2015 Urban Water Management Plan for the City of Crescent City. May 26, 2016.
Appendix A
SWRCB Funding Agreement
State Water Resources Control Board
September 17, 2021
City of Crescent City
Attn: Eric Wier, City Manager
Crescent City, CA 95531
Agreement Number: SWRCB0000000000D2005002
Project Number: C-06-8585-110
Enclosed is your Agreement for your approval and signature. This Agreement cannot be considered binding by either party until executed by the State Water Resources Control Board (State Water Board).
If you are in agreement with all terms and conditions of the Agreement, please sign and date two (2) signature pages; return only the two (2) signature pages – it is not necessary to send the entire Agreement - no later than thirty (30) calendar days from the date of this letter to:
Overnight Mail US Mail
State Water Resources Control Board
Attention: Shawnna Bell
State Water Resources Control Board
Attention: Shawnna Bell
Division of Financial Assistance Division of Financial Assistance 1001 I Street, 16th Floor P. O. Box 944212
Sacramento, CA 95814 Sacramento, CA 94244-2120
In order for the Funding Agreement to be executed by the State Water Board, the following items must also be returned with the signed signature pages:
Be aware that all projects receiving funding must comply with all applicable implementing guidelines and regulations adopted by California Department of Industrial Relations (DIR), regarding state prevailing wage requirements. You must contact DIR for guidance on how to comply. Information can be found at: http://www.dir.ca.gov/lcp.asp.
Ms. Bell may be contacted at (916) 449-5636 or [email protected] Once the Agreement is signed by both parties, we will forward an executed copy to you for your records.
Enclosures
WATER RECYCLING FUNDING PROGRAM
PLANNING GRANT
AGREEMENT No. SWRCB0000000000D2005002
by and between
CITY OF CRESCENT CITY (“Recipient”)
AND
CALIFORNIA STATE WATER RESOURCES CONTROL BOARD (“State Water Board”) for the purpose of the
RECYCLED WATER FEASABLITY STUDY (“Project”)
PROJECT NO. C-06-8585-110
o Section 79143 of the Water Code, and Resolution No. 2019-0058. o Section 80147 of the Public Resources Code, and Resolution No. 2019-0058.
PROJECT FUNDING AMOUNT: $150,000.00
GRANT COMPONENT: $150,000.00
ESTIMATED REASONABLE PROJECT COST: $150,000.00
ELIGIBLE WORK START DATE: SEPTEMBER 18, 2020
WORK COMPLETION DATE: MARCH 31, 2024
FINAL REIMBURSEMENT REQUEST DATE: SEPTEMBER 30, 2024
RECORDS RETENTION END DATE: MARCH 31, 2060
City of Crescent City
Project No. C-06-8585-110
Agreement No.: SWRCB0000000000D2005002