4. Central Anaheim Master Plan of Sanitary Sewers April 2026 — Anaheim City Council, August 25, 2026

C E N T R A L A N A H E I M

MASTER PLAN OF

SANITARY SEWERS

C I T Y O F A N A H E I M

A P R I L
2 0 2 6
P r e p a r e d B y
A K M C o n s u l t i n g E n g i n e e r s
5 5 3 W a l d
I r v i n e , C a l i f o r n i a

CITY OF ANAHEIM

CENTRAL ANAHEIM SEWER MASTER PLAN

Date of Signing: 04/22/26 Date of Signing: 04/22/26 Date of Signing: 04/22/26

Submitted to:

City of Anaheim
200 South Anaheim Boulevard
Anaheim, CA 92805

Submitted by:

AKM Consulting Engineers
553 Wald
Irvine, California 92618
(949) 753-7333

April 2026

CITY OF ANAHEIM TOC-1 Central Anaheim Sewer Master Plan R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan

TABLE OF CONTENTS

Section Page

ES EXECUTIVE SUMMARY
ES-1 General ............................................................................................................ ES-1 ES-2 Study Area ....................................................................................................... ES-1 ES-3 Existing System ............................................................................................... ES-1 ES-4 Flow Monitoring ............................................................................................... ES-3 ES-4.1 SmartCover Depth Sensor ................................................................ ES-3 ES-4.2 ADS Environmental Services ............................................................ ES-3 Es-4.3 Base Infiltration ................................................................................. ES-3 ES-4.4 Rainfall Dependent Inflow and Infiltration ......................................... ES-3 ES-5 Sewer Loads .................................................................................................... ES-3 ES-6 Hydraulic Model ............................................................................................... ES-4 ES-6.1 Model Calibration .............................................................................. ES-4 ES-6.2 Model Scenarios ............................................................................... ES-4 ES-7 Design Criteria ................................................................................................. ES-5 ES-8 Capacity Analysis ............................................................................................ ES-5 ES-9 Capital Improvement Program ......................................................................... ES-7 1 INTRODUCTION
1-1 Previous Work and Studies Completed .............................................................. 1-1 1-2 Objectives and Scope of Work of Sewer Master Plan ........................................ 1-1 1-3 Statewide General Waste Discharge Requirements .......................................... 1-2 1-4 Report Organization ........................................................................................... 1-3 1-5 Abbreviations ...................................................................................................... 1-3 1-6 Acknowledgements ............................................................................................ 1-5 2 STUDY AREA
2-1 Location .............................................................................................................. 2-1 2-2 Existing Land Use ............................................................................................... 2-1 2-2.1 Near Term Developments .................................................................... 2-4 2-3 Future Redevelopment ....................................................................................... 2-4 3 EXISTING SEWER SYSTEM
3-1 General ............................................................................................................... 3-1 3-2 Gravity Sewers ................................................................................................... 3-1 3-3 Siphons ............................................................................................................... 3-1 3-4 Split Manholes .................................................................................................... 3-1 3-5 Pipe Lining .......................................................................................................... 3-1 4 FLOW MONITORING
4-1 General ............................................................................................................. 4-1 4-2 Flow Monitoring Equipment ................................................................................ 4-1 4-2.1 SmartCover Depth Sensor ................................................................... 4-1

TABLE OF CONTENTS

CITY OF ANAHEIM TOC-2 Central Anaheim Sewer Master Plan R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
4-2.2 ADS Environmental Services ............................................................... 4-3 4-3 Flow Monitoring Results ..................................................................................... 4-3 4-4 Base Infiltration ................................................................................................... 4-7 4-5 Diurnal Patterns .................................................................................................. 4-8 4-6 Peaking Formula ................................................................................................ 4-8 4-7 Rainfall Dependent Inflow and Infiltration ........................................................... 4-9 5 SEWER LOADS
5-1 General .............................................................................................................. 5-1 5-2 Calibration Loads ................................................................................................ 5-1 5-2.1 Water Meter Billing Data ...................................................................... 5-1 5-2.2 Flow Monitoring Data ........................................................................... 5-1 5-2.3 Waste Discharge Permits .................................................................... 5-2 5-2.4 Development of Sewer Return Factors ................................................ 5-3 5-3 Sewer Load Factors ........................................................................................... 5-4 5-4 Existing Condition Loads .................................................................................... 5-7 5-4.1 Theme Park Area ................................................................................. 5-7 5-4.2 Anaheim Convention Center .............................................................. 5-10 5-4.3 Angels Stadium and Honda Center ................................................... 5-10 5-4.4 Near-Term Developments ................................................................. 5-10 5-4.5 Hotels and Motels .............................................................................. 5-10 5-4.6 Resort Area Restaurants and Retail .................................................. 5-11 5-4.7 City of Fullerton .................................................................................. 5-11 5-5 Future Condition Loads .................................................................................... 5-11 5-5.1 Theme Park Expansion ..................................................................... 5-11 5-5.2 Anaheim Garden Walk Expansion ..................................................... 5-11 5-5.3 Anaheim Public Facilities Expansion ................................................. 5-14 5-5.4 General Plan Redevelopment Areas ................................................. 5-14 5-5.5 Accessory Dwelling Units .................................................................. 5-15 6 HYDRAULIC MODEL
6-1 General ............................................................................................................. 6-1 6-2 Hydraulic Model Software ................................................................................... 6-1 6-3 Construction of Model Geometry ........................................................................ 6-2 6-3.1 Geographic Information System (GIS) ................................................. 6-2 6-3.2 Invert Elevation Datum Adjustment ..................................................... 6-2 6-3.3 Model Geometry Provision .................................................................. 6-2 6-4 Split Manholes .................................................................................................... 6-3 6-5 Siphons ............................................................................................................. 6-7 6-6 Model Calibration – Dry Weather Scenario ........................................................ 6-7 6-7 Model Calibration – Wet Weather Scenario ..................................................... 6-11 6-7.1 RDII Loads and Diurnal Patterns ....................................................... 6-11 6-7.2 Measured Flows versus Model Flows ................................................ 6-12 6-8 Model Scenarios ............................................................................................... 6-14

TABLE OF CONTENTS

CITY OF ANAHEIM TOC-3 Central Anaheim Sewer Master Plan R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
7 CAPACITY ANALYSIS
7-1 General ............................................................................................................... 7-1 7-2 Criteria ................................................................................................................ 7-1 7-2.1 Minimum Pipe Size .............................................................................. 7-1 7-2.2 Pipe Slope ........................................................................................... 7-1 7-2.3 Maximum Depth to Diameter Ratio ...................................................... 7-1 7-3 Gravity Sewer Dry Weather Flow Analysis ......................................................... 7-2 7-3.1 Existing Capacity Deficiencies ............................................................. 7-2 7-3.2 Future Capacity Deficiencies ............................................................... 7-2 7-3.3 Backflow Condition .............................................................................. 7-7 7-4 Gravity Sewer Wet Weather Flow Analysis ........................................................ 7-7 7-5 Small Diameter Gravity Sewers .......................................................................... 7-8 8 CAPITAL IMPROVEMENT PROGRAM
8-1 General ............................................................................................................... 8-1 8-2 Project Priorities ................................................................................................. 8-1 8-3 Project Costs ...................................................................................................... 8-2 8-4 Improvement Projects ......................................................................................... 8-2 8-4.1 Capacity Deficient Projects .................................................................. 8-2 8-4.2 Resort Area Projects ............................................................................ 8-3 8-4.3 Future Deficiency Location P-11 .......................................................... 8-3 8-4.4 Small Diameter Replacement Projects ................................................ 8-4

LIST OF FIGURES
Figure No. Page
ES-1 Existing Systems ............................................................................................................ ES-2 ES-2 Capacity Deficiency Locations ....................................................................................... ES-6 ES-3 Capital Improvement Project Locations ......................................................................... ES-8 2-1 Location Map ..................................................................................................................... 2-2 2-2 Existing Land Use Map ..................................................................................................... 2-3 2-3 Future Redevelopment Areas ........................................................................................... 2-5 3-1 Existing System ................................................................................................................. 3-2 3-2 Existing System Pipe Diameter and Lined Pipe Locations................................................ 3-3 3-3 Total Length of Gravity Sewer by Pipe Size ...................................................................... 3-4 4-1 Flow Monitoring Locations ................................................................................................ 4-2 4-2 Measured Flow .................................................................................................................. 4-6 4-3 24-Hour Diurnal Patterns .................................................................................................. 4-8 4-4 Relationship between Average Dry Weather Flow and Peak Dry Weather Flow .............. 4-9 4-5 ADS Flow Monitoring Site 9 (Wagner Avenue) 2/4/24-2/6/24 Storm Event .................... 4-11 4-6 ADS Flow Monitoring Site 10 (La Palma Avenue) 2/4/24-2/6/24 Storm Event ................ 4-12 4-7 ADS Flow Monitoring Site 11 (Ball Road) 2/4/24-2/6/24 Storm Event ............................ 4-13 4-8 ADS Flow Monitoring Site 13/14 (Katella Avenue) 2/4/24-2/6/24 Storm Event ............... 4-14

TABLE OF CONTENTS

CITY OF ANAHEIM TOC-4 Central Anaheim Sewer Master Plan R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
5-1 Flow Monitoring Data for ADS Site 11 .............................................................................. 5-2 5-2 Existing Conditions Additional Loading Locations ............................................................. 5-8 5-3 Future Conditions Additional Loading Locations ............................................................. 5-13 6-1 Split Manholes at Harbor Boulevard and Katella Avenue ................................................. 6-3 6-2 Split Manholes at Disneyland Drive/West Street and Katella ............................................ 6-5 6-3 Split Manholes at Ninth Street and Katella Avenue .......................................................... 6-5 6-4 Split Manholes at Cerritos Avenue and Walnut Street ...................................................... 6-6 6-5 Split Manholes at Ball Road and Walnut Street ................................................................ 6-6 6-6 Split Manholes at Manchester Avenue and Harbor Boulevard.......................................... 6-6 6-7 Dry Weather Model Calibration ADS Flow Monitoring Site 9 (Wagner Avenue) ............... 6-9 6-8 Dry Weather Model Calibration ADS Flow Monitoring Site 10 (La Palma Avenue) .......... 6-9 6-9 Dry Weather Model Calibration ADS Flow Monitoring Site 11 (Ball Road) ..................... 6-10 6-10 Dry Weather Model Calibration ADS Flow Monitoring Site 13/14 (Katella Avenue) ........ 6-10 6-11 RDII Diurnal Patterns ...................................................................................................... 6-11 6-12 Wet Weather Model Calibration ADS Flow Monitoring Site 10 (La Palma Avenue) ........ 6-12 6-13 Wet Weather Model Calibration ADS Flow Monitoring Site 11 (Ball Road)) ................... 6-13 6-14 Wet Weather Model Calibration ADS Flow Monitoring Site 13/14 (Katella Avenue) ....... 6-13 7-1 Hydraulic Elements of Channel Sections .......................................................................... 7-1 7-2 Capacity Deficiency Locations .......................................................................................... 7-6 7-3 Example Backflow Profile .................................................................................................. 7-7 8-1 Capital Improvement Project Locations ............................................................................ 8-8

LIST OF TABLES
Table No. Page
ES-1 Sewer Model Loads ....................................................................................................... ES-5 ES-2 Minimum Sewer Slopes ................................................................................................. ES-5 ES-3 Capacity Improvement Projects ..................................................................................... ES-9 1-1 Abbreviations .................................................................................................................... 1-4 2-1 Central Anaheim Land Use ............................................................................................... 2-1 3-1 Siphon Summary ......................................................................... 3-5 4-1 Flow Monitoring Results – Dry Weather Period ................................................................ 4-4 4-2 Estimated Base Infiltration for ADS Flow Monitoring Sites ................................................ 4-7 4-3 Rainfall Dependent Inflow and Infiltration for 2/4/24-2/6/24 Storm Event ........................ 4-10 5-1 OCSAN Waste Discharge Permits within the Central Anaheim Sewer Services Area ..... 5-3 5-2 Sewer Load Factors .......................................................................................................... 5-5 5-3 Revised Sewer Load Factors for Disneyland Resort......................................................... 5-7 5-4 Additional Existing Conditions Sewer Load Estimates ...................................................... 5-9 5-5 Additional Future Conditions Sewer Loads Estimates .................................................... 5-12 5-6 Additional Future Theme Park Sewer Loads................................................................... 5-14 5-7 Future Garden Walk Sewer Loads .................................................................................. 5-14 6-1 Split Manhole Summary .................................................................................................... 6-4

TABLE OF CONTENTS

CITY OF ANAHEIM TOC-5 Central Anaheim Sewer Master Plan R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
6-2 Comparison of Measured Flows and Model Calculated Flows ......................................... 6-8 6-3 Sewer Model Scenario Loads ......................................................................................... 6-14 7-1 Minimum Sewer Slopes .................................................................................................... 7-1 7-2 Existing and Future Capacity Deficiencies ........................................................................ 7-3 8-1 Unit Pipe Construction Costs ............................................................................................ 8-2 8-2 Capacity Improvement Projects ........................................................................................ 8-4

APPENDICIES
4-1 Central Anaheim Master Plan Sewer Flow Monitoring, 2024 5-1 Hotel and Motel Loads for Existing Conditions
5-2 General Plan Development Areas for Future Conditions 8-1 Small Diameter

CITY OF ANAHEIM ES-1 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan

SECTION ES

EXECUTIVE SUMMARY
ES-1 General
The City of Anaheim’s (City) previous Sewer Master Plan is dated December 2017, and the previous hydraulic model was developed and calibrated to flow monitoring data collected from ADS E nvironmental Services in 2012.

The objective of this Central Anaheim Sewer Master Plan (CASMP) is to evaluate the City’s sewer collection system under the existing and future development conditions. The scope of the CASMP includes updating the hydraulic model, procuring model software, conducting a temporary flow monitoring study, performing model calibration, evaluating existing and future sewer loading, completing system capacity analyses, developing improvement project recommendations, and preparing the sewer master plan report.

The CASMP supports the City’s compliance with the Statewide General Waste Discharge Requirements (WDRs) for sanitary sewer systems and the associated monitoring and reporting program by establishing capacity criteria, conducting peak dry weather flow (PDWF) and Peak Wet Weather Flow (PWWF) hydraulic analyses, and evaluating Rainfall Dependent Inflow and Infiltration (RDII).

ES-2 Study Area
The City is located in the north portion of Orange County, California. The City sewer system is divided into three distinct service areas: West Anaheim, Central Anaheim, and East Anaheim. This master plan examines the Central Anaheim service area, which includes approximately 8,781 acres or 13.7 square miles of residential, commercial, industrial, and institutional land. The makeup of each general section for residential, commercial, and industrial is 50.5 percent, 8.3 percent, and 12.6 percent, respectively.

Home to Disneyland Park, California Adventure Park, the Convention Center, Angel Stadium, and the Honda Center, the City receives an influx of visitors throughout the year due to commercial recreation areas and during events. Events can range from trade shows and sporting events to musical concerts and consumer expos.

Planned near-term developments within the Central Anaheim service area include four residential and mixed - use projects. Future redevelopment in the service area includes expansions at the theme parks, Anaheim Garden Walk, and municipal facilities, as well as redevelopment areas identified in the City’s 2024 General Plan Update Sewer Study Technical Memorandum.

ES-3 Existing System
The existing sewer system consists of:
 1,323,509 feet (250.7 miles) of gravity sewer pipe, ranging from 6-inches to 33-inches in diameter  75 inverted siphons
 5,585 manholes
 69 split manhole locations
 3.3 miles of pipe lining improvement projects, since 2007 The sewer collection system generally ties into the Orange County Sanitation District (OCSD). A map of the existing sewer system is shown on Figure ES-1.

CENTRAL ANAHEIM

SEWER MASTER PLAN
Existing System
Figure ES-1
PROJECT NO: 751879
DATE: April 2026
Legend
Outlets
Split Manhole
Overflow Structure
City of Anaheim Sewer
Siphon
Private Sewer
OCSD Trunk Sewer
Central Anaheim Service Area
Tributary Area
Atwood Sub-Trunk
City of Orange
Euclid Interceptor
Euclid (Area in City of Fullerton)
City of Fullerton
City of Garden Grove
Placentia Trunk
Santa Ana River Interceptor
Olive Sub-Trunk
South Anaheim Interceptor
GGSD Service Area, tributary to Orangewood Sewer

EXECUTIVE SUMMARY

CITY OF ANAHEIM ES-3 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
ES-4 Flow Monitoring
Flow monitoring and data collection were conducted to support development of sewer return ratios, hydraulic model calibration, and estimation of maximum day and peak flows. For this sewer master plan, flow monitoring data were collected by ADS Environmental Services and SmartCover at locations during two monitoring periods in 2024. The first monitoring period (February 2024 through April 2024) focused on systemwide diurnal patterns, model calibration, and wet weather evaluation, while the second period (August 2024 through October 2024) targeted detailed flow characterization for the resort and convention center areas.

ES-4.1 SmartCover Depth Sensor
As part of this effort, the City purchased fifteen (15) SmartCover devices designed for depth monitoring and flow estimation. Beyond supporting this master plan, the SmartCover system provides ongoing operational value by providing high level alarms; evaluation of rainfall-dependent inflow and infiltration (RDII); monitoring of peak flow conditions at theme park, convention center, and resort facilities ; identification of potential maintenance issues ; verification of flow split allocations ; monitoring pipe improvement projects ; and future hydraulic model updates.

ES-4.2 ADS Environmental Services
Five (5) locations were selected to monitor using the ADS Triton+, which provided flow data by directly measuring both depth and velocity with area-velocity technology, rather than depth alone as with SmartCover devices. Flow monitoring results indicate that while ADS measurements are expected to be more accurate, both systems showed similar flow trends at the five overlapping sites, likely due to laminar flow conditions and sufficient flow depth that made the sites suitable for reliable flow estimation.

ES-4.3 Base Infiltration
Base infiltration refers to groundwater entering the sewer collection system through defects in pipes, joints, connections, or manhole walls and is distinct from inflow. It is typically evaluated during periods of elevated or sustained groundwater levels. Based on the evaluation performed, base infiltration was determined to be insignificant relative to average dry weather flow.

ES-4.4 Rainfall Dependent Inflow and Infiltration
Infiltration refers to water entering the collection system from the ground through defective pipes, pipe joints, connections, or manhole wall s, while inflow refers to surface water entering the sewer system during rainfall events, typically through perforated or unsealed manhole cover s. Together, they are commonly referred to as Rainfall Dependent Inflow and Infiltration (RDII). Sewer system capacity evaluations must account for these extraneous water sources, which contribute to total system flows during wet weather conditions. Based on rainfall and flow monitoring analyses, RDII levels were determined to be low and within ranges typical of municipal sewer systems.

ES-5 Sewer Loads
The following three (3) sewer load scenarios were developed for hydraulic analysis:

1. Calibration Scenario: Sewer loads were developed using water billing data, land use information, and sewer return factors to match measured flow monitoring data. These calibrated sewer loads are the loads that all other model scenarios start with and then add to them. The total calibrated sewer loads is 18.27 mgd.

EXECUTIVE SUMMARY

CITY OF ANAHEIM ES-4 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan

2. Existing Condition Scenario: Existing loads are the calibrated loads plus increases in loads at select locations to account for higher sewer loads during maximum day conditions at major attractions and event centers. The total existing sewer loads is 20.09 mgd.

The calibrated loads are utilized for all three model scenarios for any portion of the service area that is not located near a major attraction or event center and is not expected to change landuse or densify in the future.

ES-6 Hydraulic Model
To perform a detailed analysis of the sewer collection system, it is essential to create a mathematical model that can simulate the operating and flow characteristics of the system. The simulations for this study were performed utilizing Aquanuity’s Aquatwin Sewer, which is a 64 bit ArcGIS Pro extension application. The program manages and maintains the database that stores the sewer analysis input and output results.

The sewer system is modeled by entering pipe diameters, lengths, invert elevations and pipe roughness coefficients. The sewer model includes the City’s existing manholes and sewer pipes (excluding laterals, private sewers, and sewers belonging to other agencies). The model identifies points of connection to regional facilities owned and operated by the Orange County Sanitation District (OCSD) or other adjacent agency sewer systems.

The service area contains 69 split manholes, which allow sewage to discharge in more than one direction depending on the invert elevations of the outlet pipes. For this study, split manhole locations were confirmed through plan review and/or field surveys, and flows were allocated in the model based on existing pipe sizes and invert elevations.

The current hydraulic model reflects updates from three master planning efforts over 20 years, including incorporation of as-built plans, field surveys, flow monitoring, and pipeline improvements constructed since the prior studies. The model results provide a planning- level evaluation of system capacity, and proposed improvements should be verified through detailed review of pipe geometry, flow, and CCTV inspections.

ES-6.1 Model Calibration
The hydraulic model was calibrated through an iterative process that refined system geometry, sewer loads, sewer return factors, and diurnal flow patterns using as-built plans, field survey data, and flow monitoring results.

Calibration focused on representative dry weather flow conditions, with model accuracy evaluated by comparing simulated model flows to measured field flow monitoring data. Wet weather calibration was performed by incorporating RDII into the model based on flow monitoring data from a recent storm event and iteratively adjusting RDII loads and diurnal patterns to match measured peak wet weather flows at the monitoring locations.

ES-6.2 Model Scenarios
Five (5) model scenarios were developed for the Sewer Master Plan study: Dry Weather Calibration, Wet Weather Calibration, Dry Weather Existing Condition, Wet Weather Existing Condition and Dry Weather Future Condition. The scenarios represent existing anticipated maximum day loading associated with peak activity and near-term development, and projected future conditions reflecting planned development, redevelopment, and system densification. These scenarios provide the basis for assessing system capacity and identifying potential improvement needs. The total average sewer loads for each model scenario are summarized in Table ES-1.

EXECUTIVE SUMMARY

CITY OF ANAHEIM ES-5 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table ES-1
Sewer Model Loads

ES-7 Design Criteria
The minimum design standards for the collection system pipes are summarized below.
➢ The minimum pipe size shall be 8-inches
➢ Minimum slopes are summarized in Table ES-2
➢ The minimum pipe velocity shall be 2 ft/s
➢ Maximum slopes shall not exceed 10 percent or 0.1000
➢ Maximum depth to diameter ratio (d/D)
o For existing pipes
▪ 10-inch and smaller sewers: d/D = 0.67 with peak dry weather flows ▪ 12-inch and larger sewers: d/D = 0.75 with peak dry weather flows o For new construction or future planned sewers
▪ 10-inch and smaller sewers: d/D = 0.50 with peak dry weather flows ▪ 12-inch and larger sewers: d/D = 0.60 with peak dry weather flows ES-8 Capacity Analysis
The hydraulic analysis indicates that existing capacity deficiencies in the Central Anaheim sewer system are limited to a single 85 -foot segment of 8 -inch pipe near the Anaheim Convention Center. The City’s proactive sewer system management has enhanced system performance through capacity improvement projects implemented since the 2017 Central Anaheim Sewer Master Plan and an ongoing pipe rehabilitation program, through pipe lining, initiated in 2007. Under future conditions that account for planned develop ment and redevelopment, 24,622 feet of existing sewer (about 1.9 percent of the total system length) is projected to experience capacity deficiencies based on best-available planning data. The capacity deficiencies are detailed on Figure ES-2.

Wet weather analysis based on a 5 to 10 year storm event identified no pipes flowing at full capacity.

The City also plans to upgrade remaining 6 -inch sewers to meet current design standards and support future development and redevelopment.

Scenario
Average Sewer
Load (MGD)
Dry Weather Calibration 18.3
Wet Weather Calibration 24.4
Dry Weather Existing Condition 20.1
Wet Weather Existing Condition 26.3
Dry Weather Future Condition 30.5
Pipe Size (in)
Minimum
Slope
8" 0.0036
10" 0.0030
12" 0.0024
15" and larger 0.0020
Table ES-2
Minimum Sewer Slopes
Euclid St
Harbor Blvd
Anaheim Blvd State College Blvd
Orangewood Ave
Ball Rd
Harbor Blvd
Raymond Ave
State College BlvdOrangethorpe Ave
Kraemer Blvd
Placentia Ave
Chapman Ave
Lemon St
Euclid St
Lewis St
9th St
West St
Orangewood Ave
Ball Rd
La Palma Ave La Palma Ave
Cerritos Ave
Cerritos Ave
Broadway
Santa Ana River
91-FWY
91-FWY
57-FWY
5 Fwy
5 Fwy
3 2
1 4
6 8
7 5
Katella
Deficiencies
11 1
11 9
10 12
13 7
14 0 6,0003,000
US Feet
Legend
City of Anaheim Sewer
City of Anaheim Sewer < 8" Diameter
Private Sewer
OCSD Trunk Sewer
Existing Deficiency Location
Resort Area Deficiency
Future Deficiency Location
High d/D caused by backflow (not deficient)
General Plan Update Development Areas
Central Anaheim Service Area
³
1"=3,000'
Figure ES-2

CENTRAL ANAHEIM

SEWER MASTER PLAN
Capacity Deficiency LocationsPROJECT NO: 751879
DATE: April 2026

EXECUTIVE SUMMARY

CITY OF ANAHEIM ES-7 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
ES-9 Capital Improvement Program
The City’s capital improvement projects provide a long- range planning tool and a basis for financing sewer improvements. Projects were developed from hydraulic capacity analyses, with costs based on recent City project bid data. The Central Anaheim hydraulic model has been refined over 20 years through three master plan projects, incorporating as -built plans, field observations, surveys, and flow monitoring. Model results provide a planning-level assessment of system capacity; pipe capacities and conditions should be confirmed prior to design.

The recommended gravity main capacity improvement projects are detailed in Table ES -3, and the locations are shown on Figure ES-3. A summary of the total costs for the City is as follows:

Existing Capacity Deficiency Improvements $0.94M
Future Capacity Deficiency Improvements $32.40M
Resort Area Improvement Projects $31.09M
Small Diameter Replacement Projects $223.90M
Total $288.33M
The City has reached an agreement with developers to contribute approximately $10 million toward the total resort area project costs. The City’s share of $31.09M reflects the combined cost of the Katella Avenue Sewer Project ($35.76M) and the Cerritos Avenue Sewer Project ($5.33M), minus the developer contribution.

Project priorities focus on eliminating capacity deficiencies and preventing overflows. Highest priority is assigned to the single pipe deficient under existing flows. The Resort Area projects, currently in design, are also high priority and scheduled to address increased sewage flows before the 2028 Summer Olympics.

Priorities for future deficiencies are based primarily on the rate and extent of actual development and redevelopment tributary to the affected sewers, and capacities should be reassessed as more detailed planning data becomes available. The replacement of existing 6-inch pipes with a minimum 8-inch diameter is the lowest priority.

Euclid St
Harbor Blvd
Anaheim Blvd State College Blvd
Orangewood Ave
Ball Rd
Harbor Blvd
Raymond Ave
State College BlvdOrangethorpe Ave
Kraemer Blvd
Placentia Ave
Chapman Ave
Lemon St
Euclid St
Lewis St
9th St
West St
Orangewood Ave
Ball Rd
La Palma Ave La Palma Ave
Cerritos Ave
Cerritos Ave
Broadway
Santa Ana River
91-FWY
91-FWY
57-FWY
5 Fwy
5 Fwy
P-3
P-2
P-1
P-4
P-6
P-8
P-7
P-5
Cerritos
Improvement
Katella
Improvement
Future Deficiency
Location P-11
Not deficient whentheme park flowsare diverted to thewest Harbor sewer P-9
P-10
P-13
P-12
P-14
0 6,0003,000
US Feet
1"=3,000'
³
Figure ES-3

CENTRAL ANAHEIM

SEWER MASTER PLAN
Capital Improvement Project Locations
PROJECT NO: 751879
DATE: April 2026
Legend
Improvement Locations
Project 1 (P-1)
Project 2 (P-2)
Project 3 (P-3)
Project 4 (P-4)
Project 5 (P-5)
Project 6 (P-6)
Project 7 (P-7)
Project 8 (P-8)
Project 9 (P-9)
Project 10 (P-10)
Project 12 (P-12)
Project 13 (P-13)
Project 14 (P-14)
Cerritos Improvement and
Katella Improvement Locations
Harbor Improvement
Private Sewer
OCSD Trunk Sewer
General Plan Update
Development Areas
Central Anaheim Service Area
City of Anaheim Sewer
City of Anaheim Sewer < 8"
Diameter

EXECUTIVE SUMMARY

CITY OF ANAHEIM ES-9 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table ES-3
Capacity Improvement Projects

Capital
Improvement
P
roject ID Location Pipe ID U/ S MH ID D/S MH ID
Existing
Pipe
D
iameter
(in)
Existing
Length (ft)
Existing
Slope
Peak Dry
Weather
F
low d/D
Peak Dry
Weather
F
low
(MGD)
Proposed
Pipe
D
iameter
(in)
Unit
Cost
($
/ft)1
Construction
Cost ($)2
Total Cost
($)
Project Total
Cost ($) Description
SW067222-SW067406 SW067222 S W067406_A 10 319 0.0045 0.68 0.8135 12 $1,560 $496,907 $745,360 SW077111-SW067222 SW077111 S W067222 8 85 0.0057 0.96 0.8189 12 $1,560 $132,070 $198,104 403 $628,976 $943, 465 $943,465
SW096304-SW096303 SW096304 S W096303 8 352 0.0030 0.73 0.3677 12 $1,560 $549,635 $824,452 SW096302-SW096305 SW096302 S W096305 10 368 0.0024 0.93 0.7050 12 $1,560 $574,454 $861,682 SW096303-SW096302 SW096303 S W096302 8 349 0.0028 0.85 0.4504 12 $1,560 $544,393 $816,590 SW096311-SW096310 SW096311 SW096310 8 358 0. 0024 1.00 0.3940 12 $1,560 $559,182 $838,773 SW096307-SW096305 SW096307 SW096305 8 361 0. 0024 0.86 0.6500 12 $1,560 $563,753 $845,629 SW096309-SW096308 SW096309 SW096308 8 176 0. 0029 1.00 0.6449 12 $1,560 $275,106 $412,659 SW096310-SW096309 SW096310 SW096309 8 177 0. 0029 1.00 0.6287 12 $1,560 $275,683 $413,525 SW096308-SW096307 SW096308 SW096307 8 344 0. 0024 1.00 0.6459 12 $1,560 $536,266 $804,398 SW117304-SW117303 SW117304 S W117303 10 261 0.0038 0.84 1.3872 15 $1,950 $508,677 $763,016 SW117411-SW117409 SW117411 S W117409 10 93 0.0043 1.00 0.5329 15 $1,950 $182,306 $273,458 SW117409-SW117408 SW117409 S W117408 10 211 0.0029 1.00 1.1551 15 $1,950 $412,074 $618,111 SW117408-SW117405 SW117408 S W117405 10 139 0.0019 1.00 1.1638 15 $1,950 $271,323 $406,985 SW117405-SW117404 SW117405 S W117404 10 135 0.0053 1.00 1.3153 15 $1,950 $263,270 $394,904 SW117404-SW117304 SW117404 S W117304 10 304 0.0027 1.00 1.3168 15 $1,950 $592,176 $888,264 SW117302-OT117112 SW117302 O T117112 10 21 0.0472 0.47 1.3871 15 $1,950 $40,463 $60,694 Recommended to prevent bottle neck SW117303-SW117302 SW117303 S W117302 10 120 0.0056 0.74 1.3875 15 $1,950 $234,293 $351,439 SW117412-SW117411 SW117412 S W117411 10 107 0.0037 0.80 0.4708 15 $1,950 $207,831 $311,747 SW117416-SW117409 SW117416 S W117409 8 158 0.0016 1.00 0.7818 12 $1,560 $247,057 $370,586 SW096305-SW086411 SW096305 S W086411 12 135 0.0057 1.00 1.0749 15 $1,950 $262,646 $393,968 SW086411-SW086409 SW086411 S W086409 12 284 0.0024 1.00 1.1107 15 $1,950 $554,522 $831,782 SW086409-SW086408 SW086409 S W086408 12 292 0.0023 0.91 1.1107 15 $1,950 $570,278 $855,416 SW086408-SW086407 SW086408 S W086407 12 93 0.0028 0.72 1.1107 15 $1,950 $181,428 $272,142 Recommended to prevent bottle neck SW087302-SW087301 SW087302 S W087301 10 234 0.0031 0.69 0.6961 12 $1,560 $365,087 $547,630 SW087301-SW087106 SW087301 S W087106 10 219 0.0048 0.81 0.6961 12 $1,560 $341,016 $511,524 SW107109-SW107108 SW107109 S W107108 8 361 0.0035 0.81 0.4998 12 $1,560 $563,909 $845,863 SW107110-SW107109 SW107110 S W107109 8 339 0.0014 1.00 0.3689 10 $1,300 $440,804 $661,206 SW107111-SW107110 SW107111 S W107110 8 362 0.0023 0.76 0.2004 10 $1,300 $470,574 $705,861 Project 07 E Howell Ave and S Lewis St $2,212,930
Project 05 W Midway Dr and Anaheim Blvd $2,353,309
Project 06 W Disney Way and S Harbor Blvd $1,059,154
Project 036 E Cerritos Ave and S Anaheim Blvd $3,314,984 Project 046 E Howell Ave between S Sinclair St and west of S Sunkist St $4,439,202
Project 01 South of W Eleanor Dr and S West St $943,465 Existing Improvement Project Existing Capacity Deficiency Improvement Project Total
Project 026 E Palais Rd and S Anaheim Blvd $2,502,724

EXECUTIVE SUMMARY
CITY OF ANAHEIM ES-10 Central Anaheim Sewer Master Plan R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table ES-3 (Continued)
Capacity Improvement Projects

Capital
Improvement
P
roject ID Location Pipe ID U/ S MH ID D/S MH ID
Existing
Pipe
D
iameter
(in)
Existing
Length (ft)
Existing
Slope
Peak Dry
Weather
F
low d/D
Peak Dry
Weather
F
low
(MGD)
Proposed
Pipe
D
iameter
(in)
Unit
Cost
($
/ft)1
Construction
Cost ($)2
Total Cost
($)
Project Total
Cost ($) Description
SW108208-SW108203 SW108208 S W108203 8 319 0.0024 1.00 0.4739 10 $1,300 $414,635 $621,953 SW108203-SW108201 SW108203 S W108201 8 318 0.0021 0.93 0.4625 10 $1,300 $413,465 $620,198 SW108201-SW107409 SW108201 S W107409 8 322 0.0038 0.73 0.4643 10 $1,300 $419,003 $628,505 SW119107-SW119106 SW119107 S W119106 8 275 0.0020 0.76 0.3624 10 $1,300 $357,916 $536,874 SW119108-SW119107 SW119108 S W119107 8 271 0.0020 0.73 0.3072 10 $1,300 $352,326 $528,489 SW119106-SW118309 SW119106 S W118309 8 277 0.0079 0.78 0.4470 12 $1,560 $432,806 $649,210 SW119214-SW119210 SW119214 S W119210 8 251 0.0029 0.71 0.3687 10 $1,300 $326,300 $489,450 SW119206-OC_SW119206 SW119206 O C_SW119206 8 337 0.0042 0.64 0.4026 10 $1,300 $438,243 $657,365 SW119210-SW119206 SW119210 S W119206 8 215 0.0051 0.69 0.3965 10 $1,300 $279,734 $419,601 SW102326-SW103103 SW102326 S W103132 8 358 0.0047 0.69 0.4038 10 $1,300 $465,764 $698,646 SW102415-SW102326 SW102415 S W102326 8 307 0.0038 0.64 0.3548 10 $1,300 $399,048 $598,572 SW103102-SW103101 SW103102 S W103101 8 105 0.0040 0.68 0.4526 10 $1,300 $136,500 $204,750 SW103103-SW103102 SW103103 S W103131 8 61 0.0036 0.74 0.4142 10 $1,300 $79,638 $119,457 2362 SW103132 S W103103 8 57 0.0036 0.73 0.4103 10 $1,300 $74,451 $111,677 2364 SW103131 S W103102 8 277 0.0034 0.76 0.4191 10 $1,300 $360,568 $540,852 SW069403-SW069402 SW069403 S W069402 8 314 0.0022 0.58 0.0872 12 $1,560 $490,152 $735,228 SW069402-SW069401 SW069402 S W069401 8 313 0.0021 0.68 0.3282 12 $1,560 $488,717 $733,075 SW087313-SW087311 SW087313 S W087311 21 126 0.0020 0.90 5.0336 27 $3,240 $406,976 $610,465 SW087315-SW087318 SW087315 S W087318 21 94 0.0020 0.91 4.9703 27 $3,240 $303,523 $455,285 SW087415-SW087414 SW087415 S W087414 21 147 0.0020 0.89 4.0365 27 $3,240 $474,757 $712,136 SW087414-SW087413 SW087414 S W087413 21 104 0.0020 0.92 4.8209 27 $3,240 $335,599 $503,399 SW087318-SW087313 SW087318 S W087313 21 116 0.0020 0.91 4.9742 27 $3,240 $375,678 $563,517 SW087311-SW087309 SW087311 S W087309 21 213 0.0020 0.88 5.0577 27 $3,240 $690,638 $1,035,958 SW087413-SW087425 SW087413 S W087425 21 90 0.0020 0.92 4.9617 27 $3,240 $292,248 $438,372 SW087317-SW087315 SW087317 S W087315 21 124 0.0020 0.91 4.9660 27 $3,240 $402,311 $603,466 SW087425-SW087317 SW087425 S W087317 21 239 0.0020 0.92 4.9675 27 $3,240 $775,948 $1,163,921 SW087309-SW087307 SW087309 S W087307 21 317 0.0020 0.73 5.0577 27 $3,240 $1,027,210 $1,540,814 Recommended to prevent bottle neck 12,305 $21,602,357 $32, 403,535 $32,403,535
Project 14 West of W Katella Ave and S Clementine St $7,627,333 Future Capacity Deficiency Improvement Project Total
Project 12 Southwest of E Lincoln Ave and N Evelyn Dr $2,273,954 Project 13 East of Durst St and N Lemon St $1,468,303
Project 09 South of E Orangewood Ave and S Dupont Dr $1,714,573 Project 10 North of S Towne Centre Pl and Rampart St $1,566,416 Project 08 South of E Katella Ave and S State Colleger
B lvd $1,870,655

EXECUTIVE SUMMARY
CITY OF ANAHEIM ES-11 Central Anaheim Sewer Master Plan R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table ES-3 (Continued)
Capacity Improvement Projects
Capital
Improvement
Project ID Location Pipe ID U/S MH ID D/S MH ID
Existing
Pipe
Diameter
(in)
Existing
Length (ft)
Existing
Slope
Peak Dry
Weather
Flow d/D
Peak Dry
Weather
Flow
(MGD)
Proposed
Pipe
Diameter
(in)
Unit
Cost
($/ft)1
Construction
Cost ($)2
Total Cost
($)
Project Total
Cost ($) Description
Katella Av, between Harbor Bl and West
Street - - N.A. 2,593 - - - 21 $2,520 $6,534,360 $9,801,540 Harbor Bl, south of Katella Ave - - 18 31 - - - 21 $2,520 $78,120 $117,180 Katella Av, between Harbor Bl and 1032' west
of Harbor Bl. - - 21 1,032 - 0.78 3.9995 24 $2,880 $2,972,160 $4,458,240 Katella Av, between 1032' west of Harbor Bl
and West St. - - 21 1,520 - 0.90 4.7525 27 $3,240 $4,924,800 $7,387,200 Katella Av, between West St and 663' west
of West St - - 24 663 - 0.78 5.5713 27 $3,240 $2,148,120 $3,222,180 Katella Av, between 663' west of West St
and Walnut St - - 24 674 - 0.76 6.0730 30 $3,600 $2,426,400 $3,639,600 Katella Av, between Walnut St and Ninth St - 27 1,321 - 0.67 6.6092 30 $3,600 $4,755,600 $7,133,400 - - - 15 85 0.0023 1.00 4.1727 24 $2,880 $244,800 $367,200 - - - 18 988 0.0020 1.00 4.1733 24 $2,880 $2,845,440 $4,268,160 - - - 24 160 0.0190 0.31 4.2775 24 $2,880 $460,800 $691,200 $27,390,600 $41,085,900 $41,085,900
$6,666,667 $10,000,000 $10,000,000
9,067 $20,723,933 $31,085,900 $31,085,900
Small Diameter
Replacement
Projects
Varies - - - 6 143,527 N.A. - - 8 $1,040 $149,267,872 $223,901,808 $223,901,808 143,527 $149,267,872 $223,901,808 $223,901,808
165,302 $192,223,139 $288,334,708 $288,334,708
1 Unit Costs for construction are based on $130/diameter-inch-foot for pipes 18" and smaller and $120/diameter-inch-foot for pipes 21" and larger. 2 Construction cost = length x unit cost.
3 Total costs include 50% for contingencies, design, engineering, administration, and construction management. 4 Project recommendations (Alternative 2A) provided from Anaheim Resort Area Sanitary Sewer Study, by Woodard and Curran, dated May 2025. 5 Resort Area Project Cost will be divided between Developer and City. Total City cost does not include the Developer Cost for the Resort Area improvements. 6 Upstream pipe deficiencies are resolved by downstream improvements; therefore, some deficient pipes are not included in the project recommendations.

Small Diameter Replacement Projects Total
$5,326,560
$35,759,340
Cerritos4 Cerritos Av, between Walnut St and Anaheim
Barber City Channel
Grand Total 5
Resort Area: Developer Cost5
Resort Area Project Total Cost5
Resort Area: City of Anaheim Cost5
Project in design. Recommendation is
based on future flow diverted west on
Cerritos Avenue
Katella4
New Katella Sewer
Existing North Katella Sewer
Project in design.

CITY OF ANAHEIM 1-1 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
SECTION 1

INTRODUCTION
This section provides an overview and outline for the City of Anaheim’s (City) Central Anaheim Sewer Master Plan. A brief background description, objectives and scope of work, acknowledgments, and a list of abbreviations used throughout the report are provided.
1-1 Previous Work and Studies Completed
The City of Anaheim’s (City) previous Central Anaheim Sewer Master Plan is dated December 2017. The primary objective was to develop a model of the Central Anaheim sewer system and identify sewer system needs for existing and future peak dry weather flow conditions. A hydraulic model, including all sewers owned by the City of Anaheim in the study area, was developed to simulate existing and projected development conditions. Capacity deficient sewer lines were identified and recommended solutions were developed.

The previous hydraulic model was developed and calibrated using flow monitoring data collected by ADS Environmental in 2012. This data is now outdated and does not reflect changes in water use and sewage generation resulting from recent development and redevelopment within the study area. Additionally, indoor water use and sewage generation have been influenced by the City’s ongoing water conservation efforts, as evidenced by the decrease in historical water use per capita from 129 gallons per capita per day (GPCD) in the 2015 Urban Water Management Plan (UWMP) to 107 GPCD in the 2020 UWMP.

The flow monitoring was conducted to update the sewer loading and to calibrate the hydraulic model. 1-2 Objectives and Scope of Work of Sewer Master Plan
The objective of this Central Anaheim Sewer Master Plan (CASMP) is to conduct the capacity analysis of the Central Anaheim sewer collection system under the existing and future development conditions. The scope of work for the CASMP generally included the following tasks:

1. Hydraulic Model Update
 Converted the Central Anaheim model from InfoSewer, which uses Manning’s equation, to AquaTwin Sewer, based on the EPA SWMM 5 engine, providing more accurate flow depth estimations (see Section 6-2).
 Conducted wet weather period simulations for the first time using recent flow monitoring data.  Added sewers east of Euclid Street, between Chapman Avenue and Lincoln Avenue, to improve delineation between the City’s west and central sewer study areas.  Incorporated updates for sewer projects completed since the previous model.  Developed a comprehensive inventory of all split manholes in collaboration with City staff, including updated invert elevations in the model.
 Updated sewer loads based on water meter data and sewer return factors.  Refined diurnal patterns to reflect current conditions.

2. Flow monitoring study and Rainfall Dependent Inflow and Infiltration evaluation

3. Calibration of hydraulic model to flow monitoring data

4. Development of existing and future land use and sewer load conditions

INTRODUCTION

CITY OF ANAHEIM 1-2 Central Anaheim Sewer Master Plan
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5. Evaluation of system capacity under existing and future conditions

6. Development of improvement recommendations with cost estimates

7. Preparation of Sewer Master Plan report

8. Model software procurement and training
As a planning document, the CASMP is general in nature and is predicated upon the best information available at this time. The primary sources of information used during the course of this study are as follows:

1. Central Anaheim Master Plan of Sanitary Sewers, December 2017

2. West Anaheim Master Plan of Sanitary Sewers, June 2019

3. The City of Anaheim’s Sewer Atlas Maps

4. The City of Anaheim’s Geographic Information System (GIS) data for parcels, land use, water meters, sewer system, etc.

5. The City’s Sewer Design Manual, dated September 2023

6. Temporary flow monitoring data compiled by ADS Environmental Services, May 2024

7. Temporary flow monitoring data compiled by SmartCover 2024

8. Data collected by AKM Consulting Engineers and City staff from sewer construction plans and survey data

9. Disneyland Forward Sewer Study, August 2023

10. The Disneyland Resort Specific Plan No. 92-1 Draft, September 2023

11. Anaheim Resort Area Sanitary Sewer Study Final Preliminary Design Report, dated May 2025

12. General Plan Update Draft Sewer Study Technical Memorandum, June 2024 1-3 Statewide General Waste Discharge Requirements Existing Sewer Loads The State Water Resources Control Board (SWRCB), which oversees all wastewater permitting and enforcement adopted the Statewide General Waste Discharge Requirements (WDR) for sanitary sewer systems and the associated monitoring and reporting program by issuing Order No. 2022- 0103 on December 6, 2022.

The WDR covers system capacity under Section 5.10 which states the following:
“The Enrollee shall maintain the system capacity necessary to convey: (1) base flows during dry weather conditions, and (2) wet weather peak flows consistent with designated local historic storms.

Design storms must take into account system -specific stormwater contributions via inflow and infiltration, and location -specific depth of groundwater and storm frequencies. The Enrollee shall implement capital improvements to provide adequate hydraulic capacity to:
• Meet or exceed the design criteria as defined in the Enrollee’s System Evaluation and Capacity Assurance element of its Sewer System Management Plan; and • Prevent system capacity -related spills, and adverse impacts to the treatment efficiency of downstream wastewater treatment facilities.”

INTRODUCTION

CITY OF ANAHEIM 1-3 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan

This Sewer Master Plan assists the City in compliance with Section 5.10 by:

1. Setting reasonable depth to diameter (d/D) criteria for gravity sewers under dry weather flow conditions as detailed in Section 7-2.3.

2. Conducting hydraulic analysis of the Central Anaheim sewer system under peak dry weather conditions.

3. Conducting a temporary flow monitoring study to capture wet weather data.

4. Evaluating rainfall dependent inflow and infiltration (RDII) for the storms captured during the flow monitoring period.

5. Conducting wet weather period model simulation using recent flow monitoring data.

When the City conducts the next audit and update of its Sewer System Management Plan (SSMP), in accordance with the WDR requirements, the findings and work completed as part of this Sewer Master Plan should be fully incorporated into the SSMP documentation. 1-4 Report Organization
The CASMP presents the documents and information collected and developed, methodology for preparing the hydraulic model, analyses of the existing and future system, and improvement recommendations. A brief outline of the report is as follows:

Section ES: Executive Summary
Section 1: Introduction
Section 2: Study Area
Section 3: Existing Sewer System
Section 4: Flow Monitoring
Section 5: Sewer Loads
Section 6: Hydraulic Model
Section 7: Capacity Analysis
Section 8: Capital Improvement Program
1-5 Abbreviations
To conserve space and improve readability, abbreviations have been used in this report. Each term abbreviated has been spelled out in the text the first time it is used. Subsequent usage of the term is usually by its abbreviation. The abbreviations utilized in this report are contained in Table 1-1.

INTRODUCTION

CITY OF ANAHEIM 1-4 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan

Table 1-1
Abbreviations

Abbreviation Explanation
AC, Ac Acres
ACP, acp Asbestos Cement Pipe
ADU Accessory Dwelling Unit
ADWF Average Dry Weather Flow
amsl Above Mean Sea Level
A ve Average
BI Base Infiltration
CASMP Central Anaheim Sewer Master Plan
cfs Cubic Feet per Second
CI, cip Cast Iron Pipe
CIP Capital Improvement Program
CIPP Cured-in-place
City City of Anaheim
d/D Depth to Diameter Ratio
DIP, dip Ductile Iron Pipe
DU, du Dwelling Unit
D/S Downstream
ENR Engineering News-Record
FAR Floor Area Ratio
fps, ft/s Feet per Second
ft Feet
FYE Fiscal Year Ending
gal Gallons
GIS Geographic Information System
gpcd Gallons per Capita per Day
GPD, gpd Gallons per Day
gpm Gallons per Minute
HDPE High Density Poly Ethylene
in Inch
ID Identification
I/I Inflow and Infiltration
JADU Junior Accessory Dwelling Unit
ksf Thousand Square Feet
LACSD Los Angeles County Sanitation District
LF Lineal Feet
Max Maximum
MDF Minimum Daily Flow
mg Million Gallons
MGD, mgd Million Gallons per Day

INTRODUCTION

CITY OF ANAHEIM 1-5 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan

Table 1-1 (continued)
Abbreviations

1-6 Acknowledgements
AKM Consulting Engineers would like to express their sincere appreciation to the following for their valuable assistance and support throughout the preparation of this study:
• City of Anaheim Survey Section for their diligence to acquire field data • City of Anaheim Operations Section for their diligence to provide site details • William Grigsby, Principal Civil Engineer
• Joshua Vargas, Associate Engineer

Abbreviation Explanation
MH Manhole
Min Minimum
O&M Operations and Maintenance
OCFCD Orange County Flood Control District
OCSD, OCSAN Orange County Sanitation District
PDWF Peak Dry Weather Flow
PVC Polyvinyl Chloride or Plastic Pipe
PWWF Peak Wet Weather Flow
RDII Rainfall Dependent Inflow and Infiltration
SERP Sewer Emergency Response Plan
SMP Sewer Master Plan
SRF Sewer Return Factor
SSMP Sewer System Management Plan
SSO Sanitary Sewer Overflow
SWRCB State Water Resources Control Board
TSF Thousand Square Feet
U/S Upstream
UFF Unit Flow Factor
VCP Vitrified Clay Pipe
WDR Waste Discharge Requirements

CITY OF ANAHEIM 2-1 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
SECTION 2

STUDY AREA
2-1 Location
The City of Anaheim divides its sewer system into three distinct service areas: West Anaheim, Central Anaheim, and East Anaheim. This master plan focuses on analyzing the facilities within the Central Anaheim area.

As shown on Figure 2‑1, the City of Anaheim is bordered by neighboring cities including Fullerton and Placentia to the north, Orange to the east, and Garden Grove to the south. The Central Anaheim sewer service area and West Anaheim service area are generally separated by Eucl id Street, while the Central Anaheim and East Anaheim service areas are separated by the 57 Freeway (SR‑57), the 91 Freeway (SR‑91), and Glassell Street.

The service area is easily accessible via the 5 Freeway (I‑5), the 91 Freeway (SR‑91) to the north, and the 57 Freeway (SR ‑57) to the east. The major roads within the service area include La Palma Avenue, Lincoln Avenue, Ball Road, Katella Avenue, and Orangewood Avenue traversing east to west; Euclid Street, Harbor Boulevard, and State College Boulevard traversing north to south. 2-2 Existing Land Use
The land use information utilized in the preparation of the Central Anaheim Sewer Master Plan (CASMP) is primarily based upon the City’s GIS parcel shapefile with existing land use designations. This information was supplemented by aerial photographs, specific plans, and data provided by the City’s Planning Department.

Currently, the service areas consist of primarily residential, commercial and industrial land uses. The residential land use makes up about 50.5 percent of the total net area.

Industrial land uses make up 12.6 percent of the total.

Commercial Recreation land uses, which includes
Disneyland Park, California Adventure Park, Angel
Stadium, the Convention Center, and Honda Center,
makes up 8.3 percent of the total. The locations of the various land uses throughout the service area are shown on Figure 2-2 and the total net acreage of each land use type is shown in Table 2-1.

The commercial recreation areas cause an influx of
visitors during peak seasons and during events.

Thousands of people visit the theme parks on a daily
basis. The Convention Center is host to a variety of
conventions, trade shows, consumer expos, corporate
functions, and sporting competitions . Angel Stadi um
(capacity 45,500) and Honda Center (capacity 18, 900)
host sporting and music events regularly. All of these venues contribute to daily increases in sewage generation that the City’s sewer system has to provide capacity for.

Land Use
Net Area
(Ac)1 %
Low Density 2,907.1 33.1
Low-Medium Density 657.7 7.5
Medium Density 867.6 9.9
Subtotal 4,432.4 50.5
Commercial Recreation 732.0 8.3
General Commercial 138.9 1.6
Industrial 1,104.3 12.6
Institutional 300.1 3.4
Mixed Use 23.4 0.3
Neighborhood Commercial 503.4 5.7
Office-Low or Office High 180.3 2.1
Open Space 374.2 4.3
Park 176.1 2.0
Public Facilities 2.1 0.02
Railroad 78.5 0.9
School 347.8 4.0
Vacant 63.8 0.7
Channel 324.0 3.7
Subtotal 4,349.0 49.5
Net Total Service Area 8,781.4 100.0
1 Area does not include streets and right-of-ways
Res idential
Non-Residential
Central Anaheim Land Use
Table 2-1
Euclid St
Harbor Blvd
Anaheim Blvd State College Blvd
Orangewood Ave
Ball Rd
Katella Ave
Lincoln Ave
Harbor Blvd
Raymond Ave
State College BlvdOrangethorpe Ave
Kraemer Blvd
Placentia Ave
Chapman Ave
Lemon St
Euclid St
Lewis St
9th St
West St
Orangewood Ave
Katella Ave
Ball Rd
Lincoln Ave
La Palma Ave La Palma Ave
Cerritos Ave
Cerritos Ave
Broadway
Santa Ana River
91-FWY
91-FWY
57-FWY
5 Fwy
5 Fwy
22 91
57 5

CENTRAL ANAHEIM

SEWER MASTER PLAN
Location Map
Figure 2-1
PROJECT NO: 751879
DATE: April 2026
Legend
Central Anaheim Service Area
Major Highways
City of Anaheim
City of Fullerton
City of Garden Grove
City of Orange
City of Placentia
Unincorporated Orange County
0 3,000 6,0001,500
US Feet
³
1"=3,000'
Euclid St
Harbor Blvd
Anaheim Blvd State College Blvd
Orangewood Ave
Ball Rd
Katella Ave
Lincoln Ave
Harbor Blvd
Raymond Ave
State College BlvdOrangethorpe Ave
Kraemer Blvd
Placentia Ave
Chapman Ave
Lemon St
Euclid St
Lewis St
9th St
West St
Orangewood Ave
Katella Ave
Ball Rd
Lincoln Ave
La Palma Ave La Palma Ave
Cerritos Ave
Cerritos Ave
Broadway
Santa Ana River
91-FWY
91-FWY
57-FWY
5 Fwy
5 Fwy

CONVENTION
CENTER

CALIFORNIA

ADVENTURE

DISNEYLAND

ANGEL STADIUM
22 91
57 5
0 3,000 6,0001,500
US Feet
³1"=3,000'

CENTRAL ANAHEIM

SEWER MASTER PLAN
Existing Land Use Map
Figure 2-2
PROJECT NO: 751879
DATE: April 2026
Legend
Central Anaheim Service Area
Major Highways
Land Use
Low Density
Low-Medium Density
Medium Density
Open Space
General Commercial
Neighborhood Commercial
Commercial Recreation
Office-Low or Office-High
Mixed Use
Industrial
Public Facilities
Institutional
School
Park
Railroad
Vacant
Channel

STUDY AREA

CITY OF ANAHEIM 2-4 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
2-2.1 Near-Term Developments
Planned near-term developments are shown on Figure 2-3 and include the following sites:

1. Avanti Townhomes
This is an 11.87 acre area located at 100-394 West Cerritos Avenue, west of Anaheim Boulevard. The proposed development will include 292 townhomes.

2. Legacy Anaheim
This is a 6.4 acre area located at 200 West Midway Drive, between Zeyn Street and the 5- Freeway.

The proposed development will include 156 townhomes.

3. Midway Townhomes
This is a 2.26 acre area located at 110 West Midway Drive, west of Anaheim Boulevard. The proposed development will include 86 housing units and 5 ksf of building space for community use.

4. 1220 S. Anaheim
This is a 1.9 acre area located at 1220 S. Anaheim Boulevard, south of Ball Road. The proposed development will include 233 housing units and 5 ksf of building space for community use. As of this reporting period, construction on the project has not started. 2-3 Future Redevelopment
Future redevelopment planned in the Central Anaheim service area are shown on Figure 2- 3. The details of the future expansions can be found in Section 5-5 of this report.

1. Theme Park Expansion (see Table 5-6)

2. Anaheim Garden Walk Expansion (see Table 5-7)

3. Public Facilities Expansion – Some municipal facilities including City Hall, the police department and the fire department will increase from 400 ksf to 472 ksf of indoor space.

4. General Plan Redevelopment Areas – The City’s 2024 General Plan Update Sewer Study Technical Memorandum identified redevelopment areas throughout the Central Anaheim area.

OC Vibe Development
OC Vibe is a mixed-use development, located near the Honda Center, that was concurrently under construction during the development of this study . The City conducted a separate sewer study of the on- site and downstream facilities which accounted for the future development land uses and addressed any sewer improvements needed. Therefore, OC Vibe was not considered a future redevelopment area for this Sewer Master Plan.

Euclid St
Harbor Blvd
Anaheim Blvd State College Blvd
Orangewood Ave
Ball Rd
Katella Ave
Lincoln Ave
Harbor Blvd
Raymond Ave
State College BlvdOrangethorpe Ave
Kraemer Blvd
Placentia Ave
Chapman Ave
Lemon St
Euclid St
Lewis St
9th St
West St
Orangewood Ave
Katella Ave
Ball Rd
Lincoln Ave
La Palma Ave La Palma Ave
Cerritos Ave
Cerritos Ave
Broadway
Santa Ana River
91-FWY
91-FWY
57-FWY
5 Fwy
5 Fwy
Police
Station
City Hall
Fire
Department
Midway
Townhomes
Avanti
Townhomes
1220 S.

AnaheimLegacy
Anaheim
22 91
57 5
Disneyland
California
Adventure
Honda
Center
Angel
Stadium
0 3,000 6,0001,500
US Feet
³
1"=3,000'

CENTRAL ANAHEIM

SEWER MASTER PLAN
Future Redevelopment Areas
Figure 2-3
PROJECT NO: 751879
DATE: April 2026
Legend
Central Anaheim Service Area
Major Highways
Near Term Developments
Theme Park Expansion
Anaheim Garden Walk
Anaheim Public Facilities
Future Land Use
Low Density
Low-Medium Density
Medium Density
Open Space
General Commercial
Office-Low
Mixed Use
Industrial
Institutional
School
Park

CITY OF ANAHEIM 3-1 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
SECTION 3

EXISTING SEWER SYSTEM
3-1 General
The Central Anaheim sewer system is made up of a network of gravity sewers and siphons. There are no sewer lift stations located within the Central Anaheim sewer service area. Sewage is conveyed generally north to south and east to west to points of connection with Orange County Sanitation District (OCSD) trunk sewers or adjacent agency sewers. The primary OCSD trunk sewers that traverse through Central Anaheim are the Euclid Interceptor and the Newhope Placentia Trunk Sewer , along State College Boulevard, which collect and transport sewage to OCSD’s Water Reclamation Plant No. 1 in the City of Fountain Valley. A map of the existing sewer system is shown on Figure 3-1.

The City conducted a separate sewer study for the OC Vibe mixed use development near the Honda Center.

This accounted for the future development land uses and addressed any sewer improvement needed, which will include new sewer mains that will convey flow south to Katella directly to an OCSD trunk sewer. This project will not impact the capacity of the existing Central Anaheim sewer system and therefore was not included in this study.
3-2 Gravity Sewers
The gravity system consists of 1,323,509 feet (250.7 miles) of pipe and 5,585 manholes. The majority of the gravity sewers are constructed of vitrified clay pipes with sizes ranging from 6- inches to 3 3-inches in diameter. A map of the existing system by pipe diameter is shown on Figure 3-2. The length of sewer pipe by size is shown on Figure 3-3. Approximately 61 percent of the sewers are 8-inches in diameter. 3-3 Siphons
The Central Anaheim sewer system includes 75 inverted siphons. The primary concern with each siphon is the fact that grease and debris can build up in the siphon requiring frequent maintenance to prevent sewer spills. The existing siphon locations and descriptions are listed in Table 3-1. 3-4 Split Manholes
The Central Anaheim service area contains 69 split manholes, defined as manholes with two outlet pipes.

Sewage can potentially exit the manhole in more than one direction depending on the inverts of the outlet pipes. Sometimes the invert of one outlet pipe is located much higher than the other and therefore acts as an overflow that conveys flow only under conditions of elevated sewage depth such as pipe blockages or extreme wet weather events. For this study, these locations are defined as an overflow structure.

The locations of these manholes were confirmed through plan review and/or field surveying. The dynamic model computes flows and depths across the sewer network and allocates flow at split manholes based on model flow conditions, pipe sizes and the invert elevations , rather than using fixed flow rate or percentage.

The split manhole locations are shown on Figure 3 -1. Details of each split manhole are further discussed in Section 6 and detailed in Table 6-1.
3-5 Pipe Lining
Since 2007, the City has implemented over 3.3 miles of pipe lining improvements within the Central Anaheim service area, consisting primarily of cured- in-place pipe (CIPP) installations. The locations of these projects are shown on Figure 3-2.

CENTRAL ANAHEIM

SEWER MASTER PLAN
Existing System
Figure 3-1
PROJECT NO: 751879
DATE: April 2026
Legend
Outlets
Split Manhole
Overflow Structure
Siphon
City of Anaheim Sewer
Private Sewer
OCSD Trunk Sewer
Central Anaheim Service Area
Tributary Area
Atwood Sub-Trunk
City of Orange
Euclid Interceptor
Euclid (Area in City of Fullerton)
City of Fullerton
City of Garden Grove
Placentia Trunk
Santa Ana River Interceptor
Olive Sub-Trunk
South Anaheim Interceptor
GGSD Service Area, tributary to Orangewood Sewer
Euclid St
Harbor Blvd
Anaheim Blvd State College Blvd
Orangewood Ave
Ball Rd
Harbor Blvd
Raymond Ave
State College BlvdOrangethorpe Ave
Kraemer Blvd
Placentia Ave
Chapman Ave
Lemon St
Euclid St
Lewis St
9th St
West St
Orangewood Ave
Ball Rd
La Palma Ave La Palma Ave
Cerritos Ave
Cerritos Ave
Broadway
Santa Ana River
91-FWY
91-FWY
57-FWY
5 Fwy
5 Fwy
0 3,000 6,0001,500
Feet
1"=3,000'

CENTRAL ANAHEIM

SEWER MASTER PLAN
Existing System
Pipe Diameter and Lined Pipe Locations
Figure 3-2
PROJECT NO: 751879
DATE: April 2026
³
Legend
Central Anaheim Service Area
Lined Pipe Locations
Pipe Diameter
6-inch
8-inch
10-inch
12-inch
14-inch to 16-inch
Greater than 18-inch

EXISTING SEWER SYSTEM

CITY OF ANAHEIM 3-4 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Figure 3-3
Total Length of Gravity Sewer by Pipe Size

EXISTING SEWER SYSTEM

CITY OF ANAHEIM 3-5 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table 3-1
Siphon Summary

No. Location
Pipe
Size (in)
Length
(ft)
1 938 S Roberts St,
Anaheim, CA 92802 8 269
2 225 N Loara St,
Anaheim, CA 92801 6 300
3 261-299 S Loara St,
Anaheim, CA 92802 8 345
4 1803 S Harbor Blvd,
Anaheim, CA 92802 12 47
5 1050 W Katella Ave,
Anaheim, CA 92802 8 86
10 171
21 105
10 258
10 1198 W South St,
Anaheim, CA 92802 18 54
11 515 W La Palma
Ave, Anaheim, CA
92801
12 85
12 1001 N Patt St,
Anaheim, CA 92801 12 80
13 155 W La Palma
Ave, Anaheim, CA
92801
10 43
14 900 Disneyland Dr,
Anaheim, CA 92802 33 100
16 401 E La Palma Ave,
Anaheim, CA 92801 8 105
8 1099-1079 N Wes t St,
Anaheim, CA 92801
2458
15 1310-1316 N East St,
Anaheim, CA 92805 18 275
6 704 S Loara St,
Anaheim, CA 92802
9 10278 N Wils hire
Ave, Ana hei m, CA
92801
8 88
8 474
7 802 W La Palma Ave,
Anaheim, CA 92801
No. Location Pipe
Size (in)
Length
(ft)
8 132
6 48
12 171
19 109 E Ball Rd,
Anaheim, CA 92805 8 60
21 50
24 20
21 515 W Katella Ave,
Anaheim, CA 92802 8 38
23 1207 N East St,
Anaheim, CA 92805 12 49
25 1205 E La Palma
Ave, Anaheim, CA
92805
21 31
26 1270 E Lincoln Ave,
Anaheim, CA 92805 8 53
27 1427 E Lincoln Ave,
Anaheim, CA 92805 8 63
28 1521 E Lincoln Ave,
Anaheim, CA 92805 8 54
29 1201 E Mara Pl,
Anaheim, CA 92805 8 75
30 1202 E Turin Ave,
Anaheim, CA 92805 8 308
32 1214 W Cerritos Ave,
Anaheim, CA 92802 15 85
33 1551-1561 W Katella
Ave, Anaheim, CA
92802
27 83
24 1099-1075 N East St,
Anaheim, CA 92805
31 State College Blvd,
Anaheim, CA 92806
20 W Ball Rd, Anaheim,
CA 92805
22 1300-1302 N East St,
Anaheim, CA 92805 8 291
8 321
8 215
18 300-304 E Sycamore
St, Anaheim, CA
92805
8 357
17 311-301 E North St,
Anaheim, CA 92805

EXISTING SEWER SYSTEM

CITY OF ANAHEIM 3-6 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table 3-1 (Continued)
Siphon Summary

No. Location Pipe
Size (in)
Length
(ft)
34 1561 W Katella Ave,
Anaheim, CA 92802 24 350
35 1179 Sunkis t St,
Anaheim, CA 92806 8 193
38 1181 Sunkis t St,
Anaheim, CA 92806 8 186
39 155 W La Palma
Ave, Anaheim, CA
92801
10 63
6 292
8 328
43 206-200 W Vermont
Ave, Ana hei m, CA
92805
24 47
45 425 W. Katella 8 37
46 435 W. Katella 8 37
15 34
8 23
50 Wes t St. & Ka tella 15 39
51 Kat ella and H arbor
(East Side) 15 319
44 14805-14701 E Ball
Rd, Ana hei m, CA
47 2651-2587 E South
St, Ana hei m, CA 8 618
8 398
52 899 S Harbor Blvd,
Anaheim, CA 92805 6 301
48 Hilton/Covention
Center ( Ea s t)
49 Hilton/Covention
Center (Wes t)
41 107-101 E Freedom
Ave, Ana hei m, CA
42 L a Palma A v e,
Anaheim, CA 92805
2498
10 481
8 54
40 498-420 S Wes t St,
Anaheim, CA 92805
36 W Ball Rd, Anaheim,
CA 92802
37 719-727 S Loara St
Anaheim, CA 92802
8 191
8 299
No. Location Pipe
Size (in)
Length
(ft)
53 Auburn Way,
Anaheim, CA 92805 8 99
18 344
57 1160-1180 N
Anaheim Blvd,
Anaheim, CA 92801
8 33
58 501-529 W La Palma
Ave, Ana hei m, CA
92801
10 409
59 W Ball Rd, Anaheim,
CA 92802 10 171
21 38
6 478
62 E Katella Ave,
Anaheim, CA 92805 8 150
63 1815 S Wes ts ide Dr,
Anaheim, CA 92805 8 33
64 1350-1346 S Euclid
St, Ana hei m, CA
92804
6 54
2-12 57
2-12 60
8 515
12 52855
301-329 S Rio Vis ta
St, Ana hei m, CA
92806
61 Northeas t Anaheim,
Anaheim, CA 92806
67 2098-2074
Spinnaker St,
65 Hermos a Village,
Anaheim, CA 92802
66 1172-1168 W Katella
Ave, Ana hei m, CA
8 47
8 248
56 60 Harbor Blvd,
Anaheim, CA 92801
54 Huds on Pl,
Anaheim, CA 92806 15 289
E L a Palma A v e,
Anaheim, CA 92806 8 501

EXISTING SEWER SYSTEM

CITY OF ANAHEIM 3-7 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table 3-1 (Continued)
Siphon Summary

No. Location Pipe
Size (in)
Length
(ft)
71 1153-1161 State
Colleg e Blv d,
Anaheim, CA 92806
8 698
72 2056-2124 E Cerritos
Ave, Ana hei m, CA
92806
10 240
73 Northeas t Anaheim,
Anaheim, CA 92806 12 344
75 Cinnamon Pl,
Anaheim, CA 92806 8 54
12 639
8 542
8 194
69 Northeas t Anaheim,
Anaheim, CA 92806
70 1916-1998 E Clifpark
Wa y, Ana hei m, CA
74 2805-2801 E Dutch
Ave, Ana hei m, CA
8 352
68 2047-2001 E Center
St, Ana hei m, CA
92806
CITY OF ANAHEIM 4-1 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
SECTION 4

FLOW MONITORING
4-1 General
Flow monitoring and data collection is essential in developing sewer return ratios, calibrating the system model, and estimating the maximum day and peak flows. For this sewer master plan, flow monitoring data was collected by ADS Environmental Services and SmartCover as shown on Figure 4-1.

There were two monitoring periods for this study:
 The first flow monitoring period was from February 2024 through April 2024 and included fifteen (15) SmartCover monitors and five (5) ADS monitors during the period from February 2024 to April 2024.

The monitor locations were generally chosen for purposes of developing diurnal patterns, calibrating the model and evaluating wet weather flows. The tributary areas included the majority of the Central Anaheim service area.
 The second flow monitoring period was from August 2024 through October 2024 and included ten (10) SmartCover monitors. The monitor locations were generally selected to evaluate flow depths generated from Disneyland, California Adventure, Anaheim Convention Center and the associated resort facilities in more detail.
4-2 Flow Monitoring Equipment
4-2.1 SmartCover Depth Sensor
The SmartCover SubSonic Dual Sensor has full dynamic range of a manhole with visibility from the bottom of the channel to the cover. The sensor is engineered to function in wet, humid, corrosive conditions and the patented design combines the accuracy of an ultrasonic sensor with a wide range of pressure sensors. The combination allows measurement of water level beyond the point when the sensor becomes submerged.

The SubSonic Dual Sensor has the following capabilities:
 Utilizes a satellite network or a combined satellite and cellular data for communications (not solely cellular based)
 No confined space entry for installation required
 High water level alarms
 Real time data
 Flow estimation
The SubSonic Dual Sensor measures depth, but not velocity. T herefore the calculated flow is based on the pipe diameter, slope, measured depth and Manning’s Equation. The flow is considered a “flow estimation” for the following reasons:

1. The pipe diameter, material, and slope are based on data obtained from as -built plans which may or may not reflect actual field conditions.

2. The flow depth is measured in the manhole where the pipe slope typically varies from the upstream and downstream pipes. Typical manhole designs include a 0.2 ft drop between the incoming pipe invert and outgoing pipe invert.

3. Manning’s Equation assumes uniform, steady flow and non-varying pipe roughness, which is not always the case in every pipe within the sewer system .

Euclid St
Harbor Blvd
Anaheim Blvd State College Blvd
Orangewood Ave
Ball Rd
Harbor Blvd
Raymond Ave
State College BlvdOrangethorpe Ave
Kraemer Blvd
Placentia Ave
Chapman Ave
Lemon St
Euclid St
Lewis St
9th St
West St
Orangewood Ave
Ball Rd
La Palma Ave La Palma Ave
Cerritos Ave
Cerritos Ave
Broadway
Santa Ana River
91-FWY
91-FWY
57-FWY
5 Fwy
5 Fwy
SC 3
ADS 9
SC 8
SC 5
SC 1
SC 4
SC 7
SC 10
SC 11
SC 13 SC 15
SC 6
SC 2
ADS 10
SC 9
A4
ADS 11
SC 12
A8 A6 A1
A7
ADS 13
ADS 14
SC 14
A5

CENTRAL ANAHEIM

SEWER MASTER PLAN
Flow Monitoring Locations
Figure 4-1
PROJECT NO: 751879
DATE: April 2026
Legend
Central Anaheim Service Area
OCSD Trunk Sewer
Flow Monitoring Device
ADS Site
Smart Cover Site
(Jan 24' - Apr 24')
Smart Cover Site
(Aug 24' - Oct 24')
Tributary Areas
Site SC1
Site SC2
Site SC3
Site SC4, SC5, SC6
Site SC7
Site SC8
Site ADS9, SC9
Site ADS10, SC10
Site ADS11, SC11
Site SC12
Site SC15
Site ADS13, SC13, ADS14, SC14
City of Anaheim Sewer
0 3,000 6,0001,500
US Feet
³
1"=3,000'

FLOW MONITORING
CITY OF ANAHEIM 4-3 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
The City purchased fifteen (15) SmartCover devices which are designed for depth monitoring and high level alarm notification. In addition to use as part of this master planning effort, the City may utilize the equipment in the future for the following:
 Providing high water alarms to prevent sewer overflows, particularly during wet weather events.  Assessing the impact of Rainfall Dependent Inflow and Infiltration (RDII), during wet weather events.  Monitoring the variations in flow depth due to peak flow periods at the theme parks, convention center, and resort facilities.
 Identifying increased flow depths that may indicate maintenance issues such as partial blockages.  Monitoring changes in flow depth and capacity when diversions are made at split manholes.  Estimate the amount of sewage that may need to be discharged or bypass -pumped during pipe rehabilitation projects.
 Monitor depth and flow for potential improvement projects.  Monitor storm drain systems for illicit stormwater discharge to the sewer system.  Assist with future model updates in the future.
4-2.2 ADS Environmental Services
ADS Environmental Services installed ADS Triton+ flow monitoring equipment at five (5) selected locations.

The Flow Shark Triton is an area velocity flow monitor that uses the continuity equation to calculate flow. The Continuity Equation states that the flow quantity (Q) is equal to the wetted area of the pipe (A) multiplied by the average velocity (V) of the flow: Q = A x V
The ADS Triton+ uses the Peak Combo Sensor installed at the bottom of the pipe. It includes three (3) types of data acquisition technologies:

1. Up- looking ultrasonic depth sensor using sound waves from two independent transceivers to measure depth of flow.

2. A piezo-resistive crystal to determine the difference between the hydrostatic and atmospheric pressures to calculate pressure depth.

3. A peak velocity sensor which uses ultrasonic signals to measure the peak flow velocity.

The ADS Triton+ includes data acquisition sensors and a battery powered microcomputer. The microcomputer has a processor unit, data storage, and an on-board clock to control and synchronize the sensor recordings.

The monitor was programmed to acquire and store depth of flow and velocity readings at 5- minute intervals.

The final flow monitoring report prepared by ADS Environmental Services is included in Appendix 4-1. 4-3 Flow Monitoring Results
The flow monitoring results are shown in Table 4-1 and on Figure 4-2. It includes the average, maximum, and minimum depth, velocity, and flow observed at each site. The results represent dry weather conditions as it excludes flow data from wet weather periods that were captured.

The accuracy of ADS depth and velocity calculated flow are expected to generally be higher than that of the SmartCover “flow estimation”. However, at the five monitoring sites where both SmartCover data and ADS monitoring data was available, the SmartCover results showed similar flow trends. These sites exhibited laminar flow conditions with sufficient flow depths, making them suitable for good flow estimation.

FLOW MONITORING
CITY OF ANAHEIM 4-4 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table 4-1
Flow Monitoring Results – Dry Weather Period

Minimum Average Maximum M inimum Average Maximum
SC 1 SW052317 SSGM-17594 C rescent Ave, east of Euclid St 18 0.0022 X 0.0590 0.1938 0.3845 2.0 3.0 5.0 SC 2 SW072412 SW072410-
SW072412 Lemon St, north of Lincoln Ave 18 0.0046 X 0. 6494 1.1723 1.5480 5.0 6.4 7.7 SC 3 SW074322 SW074321-
SW074322
Cottonwood Cir, north of
Vermont Ave 30 0.0009 X 0. 2880 1.0177 2.0160 1.0 4.1 8.0 Monitoring data shows very large
variances day-to-day, which could
be due to debris, flow split, and/or
l
ower depth recordings.

SC 4 SW085130 SW085131-
SW085130
Vermont Avenue, west of Lemon
St 24 0.0012 X 0. 0130 0.3305 1.1679 2.0 3.4 11.0
Monitoring data shows very large
variances day-to-day, which could
be due to debris, flow split, and/or
l
ower depth recordings.

SC 5 SW085306 SW085315-
SW085306
Lemon St, south of Vermont
A ve 21 0. 0014 X 0.3197 0.8631 1.5876 4.0 7.0 9.8
SC 6 SW085425 SW085423-
SW085425 Lemon St, north of Ball Rd 15 0.0014 X 0. 0144 0.2257 0.5665 1.0 3.9 6.5 Monitoring data shows very large
variances day-to-day, which could
be due to debris, flow split, and/or
l
ower depth recordings.

SC 7 SW094217 2382 E ast St, south of Broadway 21 0.0019 X 0.3514 0.8789 1.6069 4.0 6.3 9.1 SC 8 SW107107 SW107106-
SW107107 Lewis St, north of Howell Ave 15 0.0030 X 0. 0403 0.0954 0.1872 1.5 2.1 3.0 SC 9 SW114328 SW107106-
SW107107 18 0.0024 X 0. 2413 0.5647 0.9855 3.0 5.2 7.0
ADS 9 SW114329 SW114330-
SW114329 18 0.0018 X 0. 1714 0.5582 0.9600 3.0 5.0 6.5
SC 10 SW052206 SW052207-
SW052206 21 0.0020 X 0. 5688 1.3473 2.2406 7.0 9.4 12.1 ADS 10 SW052204 SW052205-
SW052204 24 0.0020 X 0. 4940 1.3278 2.0966 3.7 6.2 8.3
SC 11 OT055336 OT055435-
OT055336 33 0.0026 X 1. 6099 4.8228 7.8457 9.0 14.6 18.5 ADS 11 SW055334 OT055336-
OT055334 33 0.0005 X 2. 1320 4.8506 7.3490 7.9 12.7 16.4 SC 12 MAN-2104 2016 B all Rd, west of Loara St 30 0.0015 X 0.4003 0.8084 1.4196 4.0 5.9 7.8 Flow
Monitor
Site
ID
Model
Manhole ID Model Pipe ID Location
Weekday Dry Weather Flow
(mgd)
Weekday Dry Weather Depth
(in)
Comments
U/S
Pipe
Slope1
First
Flow
Monitor
P
eriod2
Second
Flow
Monitor
P
eriod3
U/S Pipe
Diameter 1
(in)
La Palma Ave, east of Laguna
St
Wagner Ave, east of State
College Blvd
Ball Rd, west of Loara St

FLOW MONITORING
CITY OF ANAHEIM 4-5 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table 4-1 (Continued)
Flow Monitoring Results – Dry Weather Period

Minimum Average Maximum Minimum A verage Maximum
SC 134 SW066331 OT066331-
OT066329 27 0.0018 X X 0. 3413 2.1300 3.8678 4.0 8.6 13.3 ADS 13 SW066329 OT066331-
OT066329 27 0.0018 X 0.6163 2. 1379 3.5107 4.5 8.7 12.9 SC 144 SW066325 SW066327-
SW066325 24 0.0020 X X 0. 3557 1.3270 2.7144 4.0 6.4 8.0 ADS 14 SW066327 SW066328-
SW066327 24 0.0020 X 0.4630 1. 4311 2.9400 4.0 7.0 10.5 SC 15 SW087414 SW087415-
SW087414 Katella Ave, east of Harbor Blvd 21 0.0020 X 0. 1656 0.5643 1.3903 3.0 4.9 9.0 A1 SW067237 SSGM-17856 West St, south of Katella Ave 24 0. 0020 X 0.0422 0.2502 0.7445 1.6 3.4 6.3 A4 SW077337 SW077339-
SW077337
Orangewood Ave, east of West
St 15 0.0042 X 0.0936 0. 3242 0.6055 2.0 3.9 5.6
A5 SW077336 SW077338-
SW077336
Orangewood Ave, east of West
St 10 0.0030 X N.A. N. A. N.A. 1.1 3.0 3.8 Flow data was unavailable.

A6 OT058209 OT057444-
OT058209_BP 9th St and Stella Ave 27 0.0018 X N. A. N.A. N.A. 7.6 10.4 13.0 Flow data was unavailable.

A7 OT057342 OT057450-
OT057342 Katella Ave, west of Angel Ct 27 0.0051 X 1. 0080 2.0160 3.6000 8.3 10.7 13.0 A8 SW057339 SW057340-
SW057339 Katella Ave, west of Angel Ct 24 0.0020 X 2. 1570 3.7986 4.8171 11.0 15.7 18.3 1 Data tak en from plan, when available.
2 First flow monitoring period was conducted between January 2024 and April 2024. 3 Second flow monitoring period was conducted between August 2024 and October 2024. 4 Block s placed in the manhole at Katella Ave/West St (diverted flow west in Katella Ave) and at Walnut St/Cerritos St (diverted flow south in West St) during the first flow monitoring period were removed during the second flow monitoring period.

U/S Pipe
Diameter 1
(in)
U/S
Pipe
Slope1
Weekday Dry Weather Flow
(mgd)
Weekday Dry Weather Depth
(in)
Comments
Second
Flow
Monitor
Period3
Flow
Monitor
Site
ID
Model
Manhole ID Model Pipe ID Location
First
Flow
Monitor
Period2
Katella Ave and Walnut St
Katella Ave, east of 9th St

FLOW MONITORING
CITY OF ANAHEIM 4-6 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Figure 4-2
Measured Flow

0.06 0.65

0.29 0.01

0.32 0.01

0.35 0.04

0.24 0.17

0.57 0.49

1.61 2.13

0.40 0.34

0.62 0.36

0.46 0.17

0.04 0.09

1.01 2.16

0.19 1.17

1.02 0.33

0.86 0.23

0.88 0.10

0.56 0.56

1.35 1.33

4.82 4.85

0.81 2.13

2.14 1.33

1.43 0.56

0.25 0.32

2.02 3.80

0.38 1.55

2.02 1.17

1.59 0.57

1.61 0.19

0.99 0.96

2.24 2.10

7.85 7.35

1.42 3.87

3.51 2.71

2.94 1.39

0.74 0.61

3.60 4.82

0.00 1.00

2.00 3.00

4.00 5.00

6.00 7.00

8.00 9.00
SC 1
SC 2
SC 3
SC 4
SC 5
SC 6
SC 7
SC 8
SC 9
ADS 9
SC 10
ADS 10
SC 11
ADS 11
SC 12
SC 13
ADS 13
SC 14
ADS 14
SC 15
A1
A4
A5*
A6*
A7
A8
Flow (mgd)
Flow Monitoring Site ID
Minimum Flow
Average Flow
Maximum Flow
* Flow Data was unavailable

FLOW MONITORING
CITY OF ANAHEIM 4-7 Central Anaheim Sewer Master Plan
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4-4 Base Infiltration
Base infiltration (BI) in the context of sewers refers to water entering the collection system from the ground through defective pipes, pipe joints, connections, or manhole walls. Inflow is surface water that enters the sewer system, through perforated or unsealed manhole covers and from illicit cross connections, typically during rainfall events, which can lead to flooding. BI is independent of inflow and is generally measured during seasonally high groundwater conditions or in areas with consistent high groundwater conditions.

Estimates of BI are based on the difference between average dry weather flow (ADWF) and minimum daily flow (MDF). If BI is excessive, the ratio of MDF/ADWF will vary or become uncharacteristically high. For each of the five (5) ADS locations where depth and velocity was measured, BI was calculated utilizing an empirical method, the Stevens/Schutzbach equation, as follows:

BI = 0.4*MDF .
1- 0.6 (MDF/ADWF)^ ADWF0.7
Where, BI = Base Infiltration
MDF = Minimum Daily Flow (mgd)
ADWF = Average Dry Weather Flow (mgd)
The Stevens/Schutzbach equation is based on traditional residential flow patterns. Reliability of the BI calculation decreases in non- residential basins, in basins where flow from cycling pump stations are being measured, and where there are significantly more than 20,000 feet of upstream pipe.

It must be noted that BI can only be estimated based on flow data alone. More accurate measurements could be collected through flow isolations where all lateral connections are plugged in isolated small areas and the flow is measured to determine the BI value entering from the pipe joints. The BI estimation method carries higher error as the amount of BI (as a % of ADWF) decreases and lower error as BI increases. Generally, BI values below 25% to 30% could represent insignificant BI. However, BI estimates exceeding 50% of the ADWF are considered more accurate and potentially very significant.

Estimated BI during the “dry weather” period for the ADS flow monitoring locations are shown in Table 4-2. The estimated BI percentages were all less than 20% and therefore could represent insignificant BI. For master planning purposes, BI was considered relatively low and was accounted for by utilizing the flow monitoring data, including BI, to establish the average flows and diurnal patterns used in the hydraulic model.

Table 4-2
Estimated Base Infiltration for ADS Flow Monitoring Sites

ADS Flow
Monitoring
S
ite ID Location
MDF
(mgd)
ADWF
(mgd)
Estimated
BI
(m
gd)
BI % of
ADWF
9 Wagner Ave, east of State
College Blvd 0.18 0.56 0. 10 18% 10 La Palma Ave, east of
Laguna St 0.49 1.33 0. 24 18%
11 Ball Rd, west of Loara St 2. 13 4.85 0.90 19% 13/14 Katella Ave 1. 18 3.57 0.49 14% MDF = Minium Daily Flow
ADWF = Average Dry Weather Flow
B
I = Base Infiltration

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4-5 Diurnal Patterns
The hydraulic model developed for this Sewer Master Plan is a dynamic model that utilizes diurnal patterns to simulate the peak flows over a 24- hour period. The diurnal patterns were developed based upon the dry weather flow monitoring data collected for this study. They represent the variations in sewage generation throughout the day and were established for residential, non-residential, and resort area land uses, as detailed on Figure 4-3. The diurnal patterns were applied to the average sewer loads and used to calibrate the model against flow monitoring data collected from January 2024 through April 2024.

Figure 4-3
24-Hour Diurnal Patterns

Future General Plan redevelopment areas are expected to include a mix of residential and commercial uses, as shown in Figure 2- 3. The hydraulic model applies a single diurnal pattern for sewer loading, and a new diurnal pattern was needed to represent how future flows for mixed use areas will vary throughout the day.

This combined pattern reflects both residential and non-residential uses and was developed by weighting each based on projected wastewater contributions for the mixed use areas . Residential uses account for about 55 percent of the flow, while non- residential uses account for about 45 percent. This blended pattern was then applied in all future model scenarios.
4-6 Peaking Formula
The City will need to run the hydraulic model in order to determine the peak flow in any sewer pipe within the Central Anaheim service area. This is because the dynamic model utilizes diurnal patterns to calculate flows at each timestep and route them through the sewer system.

Since the hydraulic model may not always be available for future capacity evaluations or sewer design projects, an alternative method for estimating peak flow in a pipe is to use an empirical peaking equation commonly used in sewer studies:

PDWF = a x ADWF b where PDWF = Peak Dry Weather Flow
ADWF = Average Dry Weather Flow
a, b = Peaking Formula Coefficients

FLOW MONITORING
CITY OF ANAHEIM 4-9 Central Anaheim Sewer Master Plan
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The coefficient “b” factor accounts for smaller tributary areas with smaller ADWF, which generally experience greater PDWF. The change in usage of one customer in a very small tributary area will have a greater effect on its corresponding PDWF than a change in usage of one customer in a very large tributary area.

In order to develop the peaking formula and establish coefficient “a” and “b”, the maximum versus average dry weather flow measured is plotted for each flow monitoring site. The peaking relationship is then based on the best fit line through the data points, as shown on Figure 4-4. The following relationship was developed from the 2024 flow monitoring data (including BI):

PDWF = 1.65 x ADWF 0.92
Note that the units of the selected peaking formula are in million gallons per day (mgd).

Figure 4-4
Relationship between Average Dry Weather Flow and Peak Dry Weather Flow

4-7 Rainfall Dependent Inflow and Infiltration
Inflow is the surface water that typically gains entry to the sewer system through perforated or unsealed manhole covers during rainfall events that can cause covers to become flooded. Inflow, in addition to infiltration is often termed Rainfall Dependent Inflow and Infiltration (RDII). RDII represents the increased amount of flow above the average flow during or due to a rainfall event. The sewer system design capacity must include allowances for these extraneous water components, which inevitably become a part of the total flow. The amount of RDII that enters the system typically depends upon the availability and location of the storm water drainage facilities, age of structures, materials and methods of construction, manhole cover openings, location of manhole, the elevation of the groundwater table, and the characteristics of the soil.

The SmartCover equipment/data services included the SmartRain feature, a non- hardware rain gauge, from January 2024 through April 2024. Rain data is gathered from National Oceanic and Atmospheric Administration (NOAA) National Weather Service and local rain gauges and provided on the user interface with the level and flow data. The two largest storm events were as follows:

1. 2/4/24-2/6/24 – approximately 4.8 inches of rain over 54 hours; 5 to 10 year storm event

FLOW MONITORING
CITY OF ANAHEIM 4-10 Central Anaheim Sewer Master Plan
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2. 2/19/24-2/21/24 – approximately 2.1 inches of rain over 46 hours; < 1 year storm event The frequency of the storm was determined utilizing the NOAA Atlas 14 Point Precipitation Frequency Estimates (https://hdsc.nws.noaa.gov/pfds/pfds_map_cont.html) for the Anaheim California location.

The ADS flow monitoring data for the highest frequency storm event was analyzed to identify and quantify RDII within the Central Anaheim service area. RDII is calculated to be the volume of sewage exceeding the average dry weather flow. The results are shown in Table 4-3. The flows and rainfall during the 2/4/24-2/6/24 storm event are plotted on Figures 4-5 through Figure 4-8 . Site 13 and Site 14 are combined due to two existing parallel pipes in Katella Avenue which capture the total flow of the upstream basin.

Table 4-3
Rainfall Dependent Inflow and Infiltration
for 2/4/24-2/6/24 Storm Event (5-yr to 10-yr Storm Frequency)

The RDII for each site was “normalized” by dividing RDII volume (gallon) by the basin size (feet of pipe) and total rainfall depth (inches). Generally, 5 gal/ft/in is considered a reasonable average in a medium density residential area. Values greater than 5 gal/ft/in are considered noteworthy and values greater than 10 gal/ft/in are considered excessive. All normalized RDII values were calculated to be less than 5 gal/ft/in, therefore indicating relatively low RDII and typical of most sewer systems.

The normalized RDII for Site 9 is considerably lower than that of the other sites, which may be due to questionable flow monitoring data. As shown on Figure 4-5, the wet weather flows (red line) were often lower than the estimated dry weather flows (green line) at Site 9. This suggests that the RDII may be underestimated.

PWWF
(mgd)
PWWF
Depth
(i
n)
PWWF
d/D
PWWF/
PDWF
Ra
tio
97 Wagner Ave,
east of State
C
ollege Blvd
18 541 80,602 4.60 103, 192 0.28 0.8325 1.1900 7.11 0.40 1.43 10 La Palma Ave,
east of Laguna
St
24 992 120,194 4.80 1, 051,166 1.82 1.8524 3.0260 10.49 0.44 1.63 11 Ball Rd, west
of Loara St 33 2,798 420,179 4.96 4, 016,981 1.93 6.4253 10.0170 21.30 0.65 1.56 13 Katella Ave
and Walnut St 27 14.38 0.53
14 Katella Ave,
east of 9th St 24 12.71 0.53
5 PDWF is based on flow monitoring data gathered for a typical week day period.

1.87 1 Rainfall inches were calculated using the SmartRain feature provided with SmartCover monitors 2 RDII was calculated to be the volume of sewage exceeding the average dry weather flow 3 Normalized RDII = volume (gal) divided by tributary sewer pipe length (ft) and the rainfall depth (in) 1,163 86,961 4.84 1,688,778 8.5630
Tribu-
tary
A
rea
(ac)
Tributary
Sewer
P
ipe
Length
(ft)
Rain-
fall
(i
n)1
RDII
(Gallons)2
Normal-
ized
RDI
I3,4
(gal/ft/in)
7 Flow monitoring data at Site 9 during this storm event is questionable, as the wet weather flows are often lower than the dry weather flows.

4.01 ADS
Site Location
Pipe
Size
(i
n)
PDWF
(mgd)5

4.5686
Wet Weather 6
4 The normalized RDII for ADS Site 13/14 includes the resort area flow but does not include the private sewers and laterals 6 Peak flow, depth, and d/D are the peak values measured during the 2/4/24-2/6/24 storm event

FLOW MONITORING
CITY OF ANAHEIM 4-11 Central Anaheim Sewer Master Plan
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Figure 4-5
ADS Flow Monitoring Site 9 (Wagner Avenue)
2/4/24-2/6/24 Storm Event

FLOW MONITORING
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Figure 4-6
ADS Flow Monitoring Site 10 (La Palma Avenue)
2/4/24-2/6/24 Storm Event

FLOW MONITORING
CITY OF ANAHEIM 4-13 Central Anaheim Sewer Master Plan
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Figure 4-7
ADS Flow Monitoring Site 11 (Ball Rd)
2/4/24-2/6/24 Storm Event

FLOW MONITORING
CITY OF ANAHEIM 4-14 Central Anaheim Sewer Master Plan
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Figure 4-8
ADS Flow Monitoring Site 13/14 (Katella Avenue)
2/4/24-2/6/24 Storm Event

FLOW MONITORING

CITY OF ANAHEIM 4-15 Central Anaheim Sewer Master Plan
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Review of the flow and rainfall graphs (Figures 4 -5 through 4-8) show that the total flow increases with the intensity of the rainfall during a storm event. As soon as the rainfall stops, the total flow reduces back down to normal (average dry day) levels within the following 12 hours. This indicates that the RDII may be primarily due to inflow (water entering system through manhole covers or cross connections). Sometimes it can take several days for the flow levels to reduce down to normal, which indicates more infiltration into a system.

The peak depth to diameter ratios (d/D) at the flow monitoring sites ranged from 0.40 to 0.65 proving that the pipes are sufficiently sized at these locations for at least a 5 year frequency storm event. There is still remaining capacity at these locations for additional wet weather flow if it were to occur during a higher frequency storm.

Although the wet weather events captured during the Sewer Master Plan indicates that RDII is not a major concern and the system was able to handle the 2/4/24- 2/6/24 storm event, the following actions are recommended for consideration:

1. Conduct further wet weather monitoring at various locations in the system to evaluate higher frequency storms. This could be accomplished by utilizing the City’s SmartCover equipment to conduct additional depth monitoring during future storm events and evaluating rainfall data.

2. Conduct smoke testing to identify potential cross connections with storm drain systems.

3. Replace manhole covers with new ones with a single vent hole or install sufficient plugs in manhole cover vent holes.

4. Seal manhole cover rims to minimize inflow from surface flooding in areas where it is known to occur.

Locations with known stormwater ponding concerns should be given higher priority. Plugs and seals should be reinstalled whenever the manhole cover is opened.

5. Conduct CCTV inspections to identify possible connections to mainlines that are contributing excessive flows during rain events, live infiltration, or structural defects where RDII can enter the sewer system.

CCTV inspections would be most effective if conducted during or shortly after storms to visually observe water entering mainline pipes through cracks and joints or from various lateral connections.

CITY OF ANAHEIM 5-1 Central Anaheim Sewer Master Plan
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SECTION 5

SEWER LOADS
5-1 General
The following three (3) sewer load scenarios were developed for hydraulic analysis:

This section describes the process of developing the sewer loads for each of the scenarios. 5-2 Calibration Loads
Water billing data, land use information and estimated sewer return factors were used to develop the calibration loads and verify that the model accurately reflected flow monitoring data collected from February 2024 through April 2024. The calibration loads essentially represent current conditions and remain the same for each parcel/development that is not expected to change for existing season and event based visitors or in the future.

The calibration loads for the Central Anaheim service area is equal to a total average dry weather flow of 18.27 mgd.
5-2.1 Water Meter Billing Data
Water meter billing data for July 2023 through June 2024 was provided for the Central Anaheim service area.

This data was linked to the GIS parcels by address, which provides the most accurate spatial distribution of the water use and subsequently sewage generation throughout the system. 5-2.2 Flow Monitoring Data
Flow monitoring data was collected as described in Section 4. For each flow monitoring site, a dry weather weekday flow estimate was developed by excluding the days with rainfall and weekend days. Weekend days were excluded as the flows typically stay consistent over the day and don’t peak as high on the weekends. As an example, the dry weather flows at ADS Site 11 is shown on Figure 5-1.

The flow patterns were consistent from day to day with similar average flows and the peak flows occurring at about the same time each day. The model loads were matched to the flow monitoring average flows for the calibration scenario.

SEWER LOADS
CITY OF ANAHEIM 5-2 Central Anaheim Sewer Master Plan
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Figure 5-1
Flow Monitoring Data for ADS Site 11 - Weekday, Dry Weather Flow Pattern

5-2.3 Waste Discharge Permits
All customers that maintain an industrial waste discharge permit with Orange County Sanitation District (OCSAN) as of January 2024 are listed in Table 5 -1. These are the customers with presumably high water consumption and associated sewage discharge.

The industrial waste discharge permits specify a “flowbase” that is derived from historical average flow data and used to establish mass -based discharge limits. The “flowbase” values do not reflect actual peak or instantaneous discharges. Therefore, the permit information was simply used to identify the customers with potential high sewage discharge to make sure the flow was accounted for in the hydraulic model. Average sewer loads were based on water use data and sewer return factors and were still utili zing developed diurnal patterns.

MBV-Cal (formerly Nor-Cal Beverage Company) has the highest permitted flowbase. Accurate representation of its discharge location was critical for modeling purposes. It was confirmed through field inspections and flow monitoring conducted at Manhole SW081119 that MBV-Cal sewage is discharged to the 18-inch sewer located in Commercial Street. The hydraulic model was set up to reflect this in all scenarios.

SEWER LOADS

CITY OF ANAHEIM 5-3 Central Anaheim Sewer Master Plan
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Table 5-1
OCSAN Waste Discharge Permits within the Central Anaheim Sewer Service Area

5-2.4 Development of Sewer Return Factors
Sewer return factors were developed to adjust the water use to equal the average sewage flows recorded at the five (5) ADS flow monitoring locations (see Section 4-3). The steps in developing the sewer return factors by land use types are listed below:

1. The City provided the address point shapefile for the service area.

2. The water billing data from fiscal year ending 2024 ( FYE2024), existing land use and flow monitoring tributary area ID was linked spatially to the address point shapefile.

3. The water billing data, land use type, parcel area, and flow monitoring designation were exported to a database.

4. Sewer return factors (SRF) were developed. Sewer loads were calculated as the product of the water use and the sewer return factors: Water use x sewer return factor = average sewer load.

5. The sewer return factors were adjusted by trial and error with a goal to match the calculated sewer loads to within 10 percent of the average sewage flow for all flow monitoring areas.

Permit
Number Company Sewer Addres s
Permit
Start Date
Permit End
Date
2024 Permit
Flowbase
(gpd)1
1-0602062 MCP Foods 424 S. Atchison St.

Anaheim, CA 92805 10/1/2023 9/30/2025 32,000
1-021090 Superior Plating 1901 E. Cerritos Ave.

Anaheim, CA 92805 12/1/2022 11/30/2024 5,000
1-021202 Transline Technology Inc. 1106 S. Technology Cir.

Anaheim, CA 92805 11/1/2023 10/31/2025 5,000
1-021253 Linco Industries Inc. 528 S. Central Park Ave.

W. Anaheim, CA 92802 7/1/2023 6/30/2025 5,000
1-602131 MBV-CA (New) 1226 N. Olive St.

Anaheim, CA 92801 11/1/2023 10/31/2025 370,000
1-021424 Kinsbursky Brothers
Supply Inc.
1314 N. Anaheim Blvd.

Anaheim, CA 92801 10/1/2022 9/30/2024 5,000
1-021656 Alsco (New) 1750 S Zeyn Street.

Anaheim, CA 92802 8/1/2022 5/31/2024 66,000
1-021674 Stepan Company 1208 N. Patt St.

Anaheim, CA 92801 6/1/2022 5/31/2024 18,000
1-521820 International Paper
Company
601 E Ball Rd.

Anaheim, CA 92805 8/1/2022 7/31/2024 18,000
1-521843 City of Anaheim Public
Utilities
210 S. Anaheim Blvd.

Anaheim, CA 92805 11/1/2022 10/31/2024 5,000
2-522759 Disneyland Resort 1313 S. Harbor Blvd.

Anaheim, CA 92803 11/1/2023 8/31/2028 Water quality
only
S-052193
Walt Disney Parks and
Resorts,
U.S. Inc. (New)
1313 S. Harbor Blvd.

Anaheim, CA 92803 12/31/2024 12/31/2024 Water quality
only
1-602027 Sioux Honey Association
Co-op
511 Katella Ave.

Anaheim, CA 92801 8/1/2023 7/31/2025 17,000
1-021070 Pacific Image Tech (New) 1875 S. Santa Cruz St.

Anaheim, CA 92805 2/1/2022 1/31/2024 5,000
1-601486 Cal NRG Operating (New) 2930 E Frontera St. Unit A St. Anaheim, CA 92806 9/1/2023 8/31/2025 9,000
1 Flowbase is used to calculate mass discharge limits, based on historical flow data and does not reflect instantaneous allowable maximum flows.

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6. There were some areas where the sewer return factor was larger than one, which is typically not the case because sewage generation should always be less than water use. Some of the reasons for this discrepancy may be error in flow monitoring data, water consumption readings, or the fact that the water billing utilized was an annual average and not the exact same time period as the flow monitoring.

The model was set up to match the flow monitoring data as close as possible even if water use in the tributary area was lower. The billing data ultimately helps in ensuring that the distribution of the loads is as accurate as possible.

7. For the areas that were not flow monitored, the developed sewer return factors were assumed to be applicable for all similar land uses.
a. The residential sewer return factor was set at 0.70 or 70 percent . This is b ased on the water consumption and flow monitoring data for the Site 9 tributary area, which consists of primarily residential land use.
b. The non-residential sewer return factor was set 0.95 or 95 percent. This is based on past planning experience. Commercial and industrial land uses typically do not have a lot of irrigation and most of the water used is returned to the sewer system.
5-3 Sewer Load Factors
Future development and redevelopment area loads were estimated using the sewer load factors shown in Table 5-2. The sewer load factors were generally based on factors developed for the following previous City studies:
 Central Anaheim Master Plan of Sanitary Sewers (CAMPSS), December 2017  Disneyland Forward Sewer Study, August 2023
 The Disneyland Resort Specific Plan No. 92-1 Draft, September 2023  General Plan Update Draft Sewer Study Technical Memorandum, June 2024  Los Angeles County Sanitation Districts (LACSD) Service Charge Rates Attendance at the Disneyland Resort plays a significant role in the sewage flows in the Central Anaheim service area. For master planning purposes, it is best to plan for maximum attendance and maximum sewage generation to ensure the downstream sewer pipe s have the capacity to convey the flows. Therefore, sewer load factors specific to the theme park area were evaluated in greater detail to ensure that the projected future sewage generation reflects historical peak conditions.

Appendix A of the 2023 Disney Forward Study is a flow monitoring study of the Disneyland Resort conducted in August 2006. The peak flow measured was 1.94 mgd. Even though it is nearly 20 years old, the flow data is actual data measured in the field and shows that the peak flow can reach 1.94 mgd. Subsequent flow monitoring may not have been conducted when the Disneyland Resort visitor attendance was high.

The sewer load factors of the Disney Forward Study were revised as shown in Table 5-3 and match the historical peak flow as closely as possible. The theme park factor was increased from 400 gpd/ksf to 460 gpd/ksf. The restaurant/retail factor was increased from 800 gpd/ksf to 1000 gpd/ksf. The hotel room factor remained at 150 gpd/room. These changes resulted in a total sewer load of 1.98 mgd from the Disneyland Resort. The updated sewer load factors are representative of high attendance at Disneyland Resort.

SEWER LOADS
CITY OF ANAHEIM 5-5 Central Anaheim Sewer Master Plan
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Table 5-2
Sewer Load Factors

Land
Use
Code1
Sewer
Load
Factor Units
Commercial Amusement/Admin Building2 100 gpd/ksf
Commercial Amusement/Theme Park2 460 gpd/ksf
1005 Commercial Athletic Club 1,700 gpd/acre
1006 Commercial Auto Dealership 1,700 gpd/acre
1007 Commercial Auto Repair/Service 2,375 gpd/acre
1008 Commercial Auto Salvage Yard 1,000 gpd/acre
1009 Commercial Bank 1,700 gpd/acre
1059 Commercial Business Park 1,700 gpd/acre
1058 Commercial Car wash 2,375 gpd/acre
Commercial Convention Center Specialty Retail3 195 gpd/ksf Commercial Convention Center3 350 gpd/ksf
Commercial General Commercial1 1,700 gpd/acre
1019 Commercial Hotel/Motel 150 gpd/room
1026 Commercial Nursery 1,700 gpd/acre
Commercial Restaurant/Retail3 1,000 gpd/ksf
1044 Commercial Retail Use 1,700 gpd/acre
1047 Commercial Service Station 1,700 gpd/acre
1048 Commercial Sex Oriented Business 1,700 gpd/acre
Commercial Special Events Center5 10 gpd/seat
1050 Commercial Theater 1,700 gpd/acre
1054 Commercial Veterinary Clinic 1,700 gpd/acre
1020 Industrial Industrial 1,700 gpd/acre
1060 Industrial Self Storage Facility 350 gpd/acre
200 gpd/du
357 gpd/ksf
225 gpd/du
237 gpd/ksf
225 gpd/du
329 gpd/ksf
200 gpd/du
317 gpd/ksf
200 gpd/du
338 gpd/ksf
200 gpd/du
339 gpd/ksf
1023 Mixed Use Mixed Use 1,700 gpd/acre
1029 Office Office Use 1,700 gpd/acre
Mixed Use
Mixed-Use Mid4
Mixed-Use Urban Core4
Mixed-Use Low-Medium4
Mixed-Use Medium4
Mixed Use
Land Use Category
Mixed Use
Mixed Use
Mixed-Use High4
Mixed-Use Industrial4
Mixed Use
Mixed Use

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Table 5-2 (Continued)
Sewer Load Factors

Land
Use
Code1
Sewer
Load
Factor Units
1062 Public and QuasiPublic City Facility 680 gpd/acre
1011 Public and QuasiPublic City Hall 680 gpd/acre
1064 Public and QuasiPublic Community or Charity Group 680 gpd/acre 1014 Public and QuasiPublic Day Care Center 815 gpd/acre 1016 Public and QuasiPublic Fire Station 815 gpd/acre
1018 Public and QuasiPublic Hospital 815 gpd/acre
1021 Public and QuasiPublic Librarv 680 gpd/acre
1022 Public and QuasiPublic Medical Office 815 gpd/acre 1063 Public and QuasiPublic Mortuarv 815 gpd/acre
1065 Public and QuasiPublic Museum 815 gpd/acre
1027 Public and QuasiPublic Nursing Home 815 gpd/acre
1035 Public and QuasiPublic Police Station 815 gpd/acre 1036 Public and QuasiPublic Post Office 680 gpd/acre
1037 Public and QuasiPublic Preschool Public 320 gpd/acre 1038 Public and QuasiPublic Private School 320 gpd/acre Public and QuasiPublic Public / Quasi-Public - Institutional 815 gpd/acre 1039 Public and QuasiPublic Public School 320 gpd/acre
1042 Public and QuasiPublic Religious Use 815 gpd/acre
1045 Public and QuasiPublic Retirement Facility 815 gpd/acre 1051 Public and QuasiPublic Train Station 680 gpd/acre
1055 Public and QuasiPublic Vocational School 320 gpd/acre 1003 Residential Apartment Residential 210 gpd/du
1012 Residential Condominium/Townhouse 240 gpd/du
1057 Residential Duplex Residential6 255 gpd/du
1025 Residential Fourplex Residential 240 gpd/du
1024 Residential Mobile Home Park 190 gpd/du
1049 Residential Single Family Residence7 250 gpd/du
1046 Residential Triplex8 245 gpd/du
6 Future Low Medium Density Residential and Corridor Density Residential Land Uses are included 7 Future Low Density Residential Land Uses are included 8 Future Medium Density Residential and MidDensity Residential Land Uses are included Land Use Category
1 Factors with Land Use Codes are from 2017 CAMPSS Report 2 Factors from 2023 Disneyland Forward Sewer Study
3 Convention Center factors from 2017 CAMPSS Report, Appendix A: TM 6 4 Factors from updated 2024 General Plan Update Draft Sewer Study. Mixed use estimates include both residential and non-residential components. 5 Angels Stadium and Honda Center factors based on LACSD Service Charge Loading estimates for special events center
Note: du = dwelling unit; gpd = gallons per day; k sf = thousand square feet

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Table 5-3
Revised Sewer Load Factors for Disneyland Resort

5-4 Existing Condition Loads
For the Sewer Master Plan study, the existing condition loads were defined by the anticipated maximum day loads. The City is home to major attractions and event centers that draw high volumes of seasonal and event- based visitors , including Disneyland, Disney California Adventure, the Anaheim Convention Center, Angel Stadium, and Honda Center.

Calibrated loads represent flows observed in the sewer system during the calibration period and serve as the baseline for developing existing condition loads. Select loads were updated to account for additional sewage generated when attractions and event centers operate at high capacity , representing typical maximum day conditions. Estimated loads from developments expected to be occupied in the near term (i.e., currently in design or under construction) were also added to the existing condition loads.

The existing condition loads are summarized in Table 5-4 and the loading locations are shown on Figure 5-2.

The total existing condition loads is 20.09 mgd. The methodology for calculating the existing condition loads is described in the following subsections.
5-4.1 Theme Park Area
The theme park area includes Disneyland Park and California Adventure and is bounded by Walnut Street to the west, Ball Road to the north, Harbor Boulevard to the east, and Katella Avenue to the south. Flow monitoring was conducted in April 2022 for the Disneyland Forward Sewer Study. The sewage generated within the theme parks was monitored at eight locations prior to entering the City’s sewer system. The maximum day flow of

1.98 mgd was distributed in the existing conditions based on the relative proportions of flow measured in 2022.

The distribution to the eight locations is shown in Table 5-4. These loads will replace the calibration loads which were likely representative of less than full capacity.

Land Use
Maximum Day
Sewer Load
(mgd)3
Theme Park 3,193 ksf 460 gpd/ksf 1.47
Restaurant/Retail 160 ksf 1000 gpd/ksf 0.16
Hotel Rooms 2,342 rooms 150 gpd/room 0.35

1.98 3 Maximum Day Sewer Load is the average sewage flow when Disneyland Resort attendance is high
Note: du = dwelling unit; gpd = gallons per day; ksf = thousand square feet Revis ed Sewer
Load Factor2
Existing
Landuse Data1
Total Maximum Day Sewage Flow
1 Land use data from 2023 Disneyland Forward Study
2 Theme Park factor increased from 400 gpd/ksf to 460 gpd/ksf; Restaurant/Retail factor increased from 800 gpd/ksf to 1000 gpd/ksf Euclid St
Harbor Blvd
Anaheim Blvd State College Blvd
Orangewood Ave
Ball Rd
Katella Ave
Lincoln Ave
Harbor Blvd
Raymond Ave
State College BlvdOrangethorpe Ave
Kraemer Blvd
Placentia Ave
Chapman Ave
Lemon St
Euclid St
Lewis St
9th St
West St
Orangewood Ave
Katella Ave
Ball Rd
Lincoln Ave
La Palma Ave La Palma Ave
Cerritos Ave
Cerritos Ave
Broadway
Santa Ana River
91-FWY
91-FWY
57-FWY
5 Fwy
5 Fwy
SW086411
SW077111
SW118401
SW086310
SW076308
SW086412
SW118207
SW066209
SW066207
SW076312
SW086230
SW065401
SW087203
SW066204
SW066202
SW127207
SSMH-05698
OT080407

CENTRAL ANAHEIM

SEWER MASTER PLAN
Existing Conditions
Additional Loading Locations
Figure 5-2
PROJECT NO: 751879
DATE: April 2026
Legend
Private Sewer
OCSD Trunk Sewer
Existing Hotels and Motels
Resort Area Restaurants and Retail
Resort Area Boundary
Central Anaheim Service Area
Existing Loading MH
Theme Park
Convention Center
Near Term Development
Angels Stadium
Honda Center
Fullerton
0 6,0003,000
US Feet
1"=3,000' ³

SEWER LOADS
CITY OF ANAHEIM 5-9 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table 5-4
Additional Existing Conditions Sewer Load Estimates

Type Location
Model
Manhole ID
Dwelling
Units (du)
Building
Area
(ksf)
No. of
Seats
Sewer Load
Factor1
Existing
Sewer
Load
(mgd)
Magic Wy, west of Walnut St SW065401 - - - - 0.7106
Disneyland Dr, north of Katella
Av SSMH-05698 - - - - 0.5118
Katella Av, east of Disneyland Dr
(north sewer) SW076312 - - - - 0.2203
Cerritos Av extension, east of
Walnut St. SW066209 - - - - 0.0121
Walnut St, north of Laster Av
(east sewer) SW066207 - - - - 0.1908
Harbor Bl, south of Manchester
Av (west sewer) SW086310 - - - - 0.2082
Walnut St, south of Lynne Av
(east sewer) SW066202 - - - - 0.1128
Walnut St, north of Calle de Las
Estrellas (east sewer) SW066204 - - - - 0.0134
Subtotal 1.9801
West St SW077111 - 933 - 329 gpd/ksf 0.3266
Katella Av SW076308 - 228 - 329 gpd/ksf 0.0798
Subtotal 0.4064
Gene Autry Way extension, east
of State College Bl SW118401 - - 22,750 10 gpd/seat 0.2275 Tributary to OCSD Santa Ana
Trunk Sewer SW118207 - - 22,750 10 gpd/seat 0.2275
Subtotal 0.4550
Honda Center Douglas Rd, north of Katella Av. SW127207 - - 18,900 10 gpd/seat 0.1890 Avanti Townhomes: Cerritos and
Anaheim SW087203 292 - - 240 gpd/du 0.0701
Legacy Anaheim: Willow and
Midway SW086412 156 - - 240 gpd/du 0.0374
86 - - 225 gpd/du
- 5 - 329 gpd/ksf
233 - - 225 gpd/du
- 5 - 329 gpd/ksf
Subtotal 0.1825
Hotels and Motels 2.6805
Resort Area Restaurants
and Retail 0.0245
City of Fullerton4 Raymond Av, north of 91 Fwy OT080407 - - - - 0.0478 Total 5.9658
5 As of this reporting period, construction on this project has not started. 3 Near-term developments identified in 2023 Disneyland Forward Study and updated based on discussions with City Planning Department
Theme Park2
Anaheim Convention
Center
Angels Stadium
Near Term Development3
Hotel and motels assumed at full occupancy. See Appendix 5-1 for details.

Calibration loads increased by 20%
1 Sewer load Factors from Table 5-3
2 Maximum day sewer loads represent the historical peak sewage generation and are proportionally distributed based on historical flow monitoring data that was conducted in April 2022 for the 2023 Disneyland Forward Study. 4 City of Fullerton flow obtained from the City of Fullertoon hydraulic model. 110 W. Midway Apartment:

Anaheim and Midway
1200 S. Anaheim (south of Ball)5
SW086411
SW086230

0.0210

0.0539

SEWER LOADS
CITY OF ANAHEIM 5-10 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan

5-4.2 Anaheim Convention Center
Maximum day sewer loads for the Anaheim Convention Center were estimated using a sewer load factor of 350 gpd/ksf, applied to the building area data obtained from the City’s website:
https://www.visitanaheim.org/meetings/anaheim-convention-center/ The resulting maximum day sewer loads were estimated for the laterals tributary to West Street and Katella Avenue as follows:
 West Street (MH SW076306): 933 ksf x 350 gpd/ksf = 0.3266 mgd  Katella Avenue (MH SW076308): 228 ksf x 350 gpd/ksf = 0.0798 mgd These loads will replace the calibration loads which were likely representative of less than full capacity. 5-4.3 Angels Stadium and Honda Center
Maximum day sewer loads for the Angels Stadium and the Honda Center were estimated using a sewer load factor 10 gpd/seat, representative of special event centers.  Angels Stadium: 45,500 seats x 10 gpd/seat = 0.4550 mgd (MH SW118401 and SW118207)  Honda Center: 18,900 seats x 10 gpd/seat = 0.1890 mgd (MH SW0127207) These loads will replace the calibration loads which were likely representative of less than full capacity. 5-4.4 Near-Term Developments
Planned near-term developments identified in the Disneyland Forward Sewer Study were reviewed and updated based on follow -up discussions with the City Planning Department . The developments listed below are expected to be constructed and occupied in the near future and therefore have been incorporated into the existing condition scenario to ensure that flows reflect realistic short -term conditions. The near-term development sewer load estimates are as follows:
 Avanti Townhomes (Cerritos Av and Anaheim Bl.): 292 du x 240 gpd/du = 0.0701 mgd  Legacy Anaheim (Willow St and Midway Dr.):156 du x 240 gpd/du = 0.0374 mgd  110 West Midway Apartment (Anaheim Bl and Midway Dr.) (86 du x 225 gpd/du) + (5 ksf x 329 gpd/ksf) = 0.0210 mgd  1220 S. Anaheim (Anaheim Bl, south of Ball Rd.):
(As of this reporting period, construction on the project has not started) (233 du x 225 du) +(5 ksf x 329 gpd/ksf) = 0.0539 mgd
These loads will replace the calibration loads which represent the current developments. 5-4.5 Hotels and Motels
Sewer loads for hotels and motels were estimated assuming full occupancy and a sewer load factor of 150 gpd/room. This represents maximum occupancy of all hotels and motels. The number of rooms and resulting maximum day sewer loads are summarized in Appendix 5-1. The total load for hotels and motels is 2.6805 mgd. This load will replace the calibration loads which were likely representative of less than full occupancy.

SEWER LOADS
CITY OF ANAHEIM 5-11 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
5-4.6 Resort Area Restaurants and Retail
Maximum day sewer loads for restaurants and retail uses within the resort area were estimated by increasing the calibration loads by 20 percent. The total additional load of 0.0245 mgd was implemented to account for peak attendance at restaurants and retail businesses.
5-4.7 City of Fullerton
The sewage flow from the City of Fullerton at the connection near Raymond Avenue north of the 91 -Freeway was set at 0.0478 mgd. This flow value was obtained from the City of Fullerton’s current hydraulic model, which was developed as part of the 2024 Fullerton Sewer Master Plan Update. 5-5 Future Condition Loads
The future condition loads build upon the existing condition loads, which represent anticipated maximum day conditions. The existing loads were maintained in areas where land use is not expected to change. Increases in sewage loads were applied in areas where new development, redevelopment, or densification is planned.

Additional future loads were added/increased specifically in the following locations:
 Theme Park Expansion
 Anaheim Convention Center Expansion
 Anaheim Garden Walk Expansion
 Public Facilities Expansion – Civic Center, Police Department, Fire Department  General Plan Redevelopment Areas
 Accessory Dwelling Units (ADUs) in Low Density Residential Areas The future loads developed for the future condition scenario are summarized in Table 5- 5 and the loading locations are shown on Figure 5 -3. The total future conditions loads is 30.47 mgd. The methodology for calculating the future loads is described in the following subsections. 5-5.1 Theme Park Expansion
Future maximum day sewer loads for the theme park area, including Disneyland Park and California Adventure, were estimated using land use projections from the 2023 Disneyland Forward Sewer Study the corresponding sewer load factors. Future land use projections were provided for nine specific connection points to the City’s sewer system which are detailed in Table 5- 6. The future loads are due to the future Theme Park expansion and therefore are in addition to the loads in the existing scenario. 5-5.2 Anaheim Garden Walk Expansion
The Anaheim Garden Walk is a mixed use development project, located south of Disney Way, between Harbor Boulevard and Clementine Street. Future sewer loads were estimated using future projections from The Disneyland Resort Specific Plan No. 92-1 and associated sewer load factors, which are detailed in Table 5 -7.

Due to limited detail for the planned expansion areas tributary to the City’s sewer system, projected loads were proportionally distributed based on the way existing load allocations are distributed. Assumed connection points are shown in Table 5-5.

SEWER LOADS
CITY OF ANAHEIM 5-12 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table 5-5
Additional Future Conditions Sewer Load Estimates

Type Location
Model
Junction
Future Sewer
Load
(mgd)
Walnut St OT065317 0.2109
Disneyland Dr SW066402 0.0068
Magic Wy SW065410 0.6375
Harbor Bl SW086310 0.2673
Katella Av SW076312 0.2673
Ball Rd SW075201 0.0170
Katella Av SW087414 0.4993
Harbor Bl HARBOR2 0.9793
Clementine St SW087201 0.1674
Subtotal 3.0527
Disney Wy, east of Harbor Bl SW087303 0.0228
Clementine St and Disney Wy SW087401 0.0135
Clementine St, south of Disney Wy SW087402 0.0078
Katella Ave, west of Clementine St SW087423 0.0907
Katella Ave, west of Clementine St SW087425 0.0052
Clementine St and Katella Av SW087411 0.0063
Disney Wy, east of Harbor Bl SW087302 0.3815
Clementine St, north of Katella Av SW087406 0.3065
Subtotal 0.8345
425 S Harbor Blvd SW073223 0.0030
201 S Anaheim Blvd SW083303 0.0029
200 S Anaheim Blvd SW083308 0.0023
210 S Anaheim Blvd SW083306 0.0012
250 E Center St SW083307 0.0011
225 S Philadelphia St SW083325 0.0003
Subtotal 0.0106
General Plan
Developments4 7.6138
Accessory Dwelling Units 5 0.0687
Total 11.5803
1 See Table 5-6 for detailed calculations of sewer loads. 3 Sewer loads increased by 20% to reflect future 20% expansion in building area.

Theme Park Expansion1
Anaheim Garden Walk2
Anaheim Public Facilities 3
2 See Table 5-7 for detailed calculations of sewer loads. Loads are proportionally distributed 4 See Appendix 5-2 for detailed calculations of sewer loads 5 Assumed 5% of low density residential parcels will add an ADU in the future Euclid St
Harbor Blvd
Anaheim Blvd State College Blvd
Orangewood Ave
Ball Rd
Katella Ave
Lincoln Ave
Harbor Blvd
Raymond Ave
State College BlvdOrangethorpe Ave
Kraemer Blvd
Placentia Ave
Chapman Ave
Lemon St
Euclid St
Lewis St
9th St
West St
Orangewood Ave
Katella Ave
Ball Rd
Lincoln Ave
La Palma Ave La Palma Ave
Cerritos Ave
Cerritos Ave
Broadway
Santa Ana River
91-FWY
91-FWY
57-FWY
5 Fwy
5 Fwy
OT065317
SW073223
SW083307
SW087303SW087302
SW086310
SW065410
SW087406
SW087411
SW083306
SW075201
SW087402
SW076312
SW087201
SW087401
SW087423SW066402
SW083325
SW083308SW083303
HARBOR2
SW087425SW087414

CENTRAL ANAHEIM

SEWER MASTER PLAN
Future Conditions
Additional Loading Locations
Figure 5-3
PROJECT NO: 751879
DATE: April 2026
0 6,0003,000
US Feet
1"=3,000' ³
Legend
City of Anaheim Sewer
City of Anaheim Sewer
Private Sewer
OCSD Trunk Sewer
Central Anaheim Service Area
Future Loading MH
Theme Park
Anaheim Public Facility
Garden Walk
General Plan Update Area
Resourt Area Boundary
City of Anaheim Sewer

SEWER LOADS
CITY OF ANAHEIM 5-14 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table 5-6
Additional Future Theme Park Sewer Loads

Table 5-7
Future Garden Walk Sewer Loads

5-5.3 Anaheim Public Facilities Expansion
The City is in the planning stages of expanding some municipal facilities including City Hall, the police department, and the fire department from 400 ksf to 472 ksf of indoor space. The future sewer loads of 0.0106 mgd were estimated by increasing the existing loads (originally derived from water billing data and sewer return ratios) by 20 percent, which corresponds to the planned increase of building area. 5-5.4 General Plan Redevelopment Areas
As part of the 2024 General Plan Update Draft Sewer Study Technical Memorandum, a GIS shapefile and associated database were developed to identify future development and redevelopment areas. The planning dataset included detailed information on land use type, number of dwelli ng units, and building area. Using the sewer load factors in Table 5-2, future maximum day sew er loads were calculated. These projected loads of

7.6138 mgd were incorporated into the future condition scenario, replacing the existing loads. The future sewer loads are summarized in Appendix 5-2, and the associated areas are shown on Figure 5-2.

Location MH ID
Hote ls
(rooms)
Theme
Park (ksf)
Admin
Building
(ksf)
Res taurant
Retail (ksf)
Maximum
Day Sewer
Load (mgd)
Walnut St OT065317 1,406 0.2109
Disneyland Dr SW066402 45 0.0068
Magic Wy SW065410 1,162 103 0.6375
Harbor Bl SW075417 581 0.2673
Katella Av SW076312 581 0.2673
Ball Rd SW075201 170 0.0170
Katella Av SW087414 1,852 312 78 0.4993
Harbor Bl HARBOR2 3,348 672 168 0.9793
Clementine St SW087201 1,116 0.1674
150 460 100 1,000
gpd/room gpd/ksf gpd/ksf gpd/ksf
7,767 3,308 170 349 3.0527
**Land use data and sewer load factors from 2023 Disney Forward Study Sewer Load Factors
Sewer Load Factor Units
Total
Land Use
Future Sewer
Load (mgd)
Restaurant/Retail 590 ksf 1000 gpd/ksf 0.5903
Hotel Rooms 1,628 rooms 150 gpd/room 0.2442

0.8345
* Future loads assume a maximum day capacity at Garden Walk Future Land
Us e Data
Sewer Load
Factor
Total

SEWER LOADS
CITY OF ANAHEIM 5-15 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
5-5.5 Accessory Dwelling Units
Future demands may be affected by regulations related to accessory dwelling units (ADU) and junior accessory dwelling units (JADU). ADUs are attached or detached residential dwelling units that provide complete, independent living facilities for one or more people, and are located on a lot with a proposed or existing primary residence. JADUs are no more than 500 square feet in size.

Since 2016, ADU laws in California have continued to evolve to further lower barriers to the development of more affordable housing as the state works to address the housing crisis. ADUs are, by definition, created in areas that are already developed but where land may be underutilized.

State ADU Law has been revised over the years to improve its effectiveness in creating more housing units. Major changes to State ADU Law went into effect January 1, 2023, January 1, 2024, and January 1, 2025. Per Government Code section 66323, there are four categories of ADUs and JADUs that must be approved ministerially:

1. Single Family Converted ADU – one ADU or JADU per lot is permitted within the converted space of a proposed or existing single-family dwelling or accessory structure

2. Single Family Detached ADU – one detached new construction ADU with maximum unit size of 800 square feet is permitted

3. Multifamily Converted ADU – ADUs may be created within the portions of existing multifamily structures that are not used as livable space

4. Multifamily Detached ADU – Up to two detached ADUs are allowed on a lot that has a proposed multifamily dwelling, or up to eight detached ADUs are allowed on a lot with an existing multifamily dwelling, not to exceed the number of existing units on the lot.

Based on the City’s current ADU information, less than 50 ADUs have been approved in the Central Anaheim area. This is an insignificant amount considering there are more than 16,000 low density residential parcels in Central Anaheim. Therefor e, for this study, future sewer loads due to ADUs are expected to be more than adequately represented by assuming that 5 percent of low-density residential parcels will add an ADU.

Senate Bill 1157 amending California Water Code Section 10609.4, set the residential indoor water use standard at 55 gallons per capita day (gpcd) until January 1, 2025. It is set to be lowered to 42 gpcd beginning January 1, 2030. Based on this standard, it is estimated that each future ADU would add about 84 gpd to the sewer system. This assumes 42 gallons per day of sewage generation and 2 persons per dwelling unit. For modeling purposes, 5% of the estimated 84 gpd (4.2 gpd) was added to each low den sity residential parcel in the future scenario. The loads were applied to each parcel since it is unknown exactly where the ADUs may be developed. There are about 16,359 low density residential parcels in the Central Anaheim service area.

Therefore, the total added sewer load due to future ADU’s is 0.0687 mgd.

CITY OF ANAHEIM 6-1 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
SECTION 6

HYDRAULIC MODEL
6-1 General
To perform a detailed analysis of the sewer collection system, it is essential to create a mathematical model that is capable of simulating the operating and flow characteristics of the system. This section describes the development of the sewer hydraulic model.
6-2 Hydraulic Model Software
The simulations for this study were performed utilizing Aquanuity’s Aquatwin Sewer, which is a 64 bit ArcGIS Pro extension application. The program is powered by the latest version of the industry standard EPA SWMM 5 engine. The software solves the Saint -Venant equation for sewer node- link networks, computing the node level, pipe flow, and pipe level for each time step. Saint-Venant equations are partial differential equations that maintain the conservation of mass and momentum and are used to model unst eady, non-uniform flow, which are flow conditions that vary over time and along the length of the pipe. Unlike programs that use Manning’s equation alone, Aquatwin Sewer accounts for channel storage, backwater effects, entrance/exit losses, pressurized flow and supercritical flow, which will result in a model that more accurately estimates the flow depths in the pipes.

The sewer system is modeled by entering all information for existing pipes, manholes, and connection points to regional facilities owned and operated by Orange County Sanitation District (OCSD) or other adjacent sewer systems. The model excludes laterals, private sewers, and sewers belonging to other agencies. Generally, the following parameters are input into the model:
 Pipes: diameter, upstream invert elevation, downstream invert elevation, length, roughness coefficient  Manholes: diameter, rim elevation, invert elevation
The model utilizes the average dry weather flows specified by the user and determines peak flows based upon established diurnal patterns.

At the completion of a model run, output data is generated hourly for the 24-hour run. The output data includes a summary of the following data:

1. Pipe slope

2. Pipe flow

3. Pipe velocity

4. Pipe depth of flow - Pipe depth is calculated as the average depth of the upstream and downstream model junction (i.e. manhole)

5. Pipe depth to diameter ratio (d/D)

6. Junction inflow (i.e. sewage load at manhole)

7. Junction depth (i.e. sewage depth in manhole)

HYDRAULIC MODEL
CITY OF ANAHEIM 6-2 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
6-3 Construction of Model Geometry
6-3.1 Geographic Information System (GIS)
The City’s hydraulic models prepared for the Central Anaheim Sewer Master Plan (2017) and the West Anaheim Sewer Master Plan (2019) were utilized to develop the base pipe and manhole network for the updated sewer model. The model data was utilized in lieu of the City’s Sewer GIS because the GIS did not include invert elevations or slope information for the sewer pipes, except for facilities constructed in recent years. The City’s sewer GIS has been updated independently of the hydraulic model. Therefore, the two datasets do not currently have a one-to-one correspondence. The figures and tables in this master plan report reference the pipe and manhole IDs and geometry in the hydraulic model only.

For this Master Plan, the Central Anaheim sewer service area was expanded to include the areas east of Euclid Avenue that are tributary to the OCSD Euclid Interceptor, with Euclid Avenue serving as the western boundary of the service area. Some of the sewer pipes and manholes adjacent to Euclid Avenue were extracted from the West Anaheim hydraulic model and added to the Central Anaheim hydraulic model.

The following general steps were completed to construct the model geometry:

1. The existing Central Anaheim and West Anaheim hydraulic model pipe and manhole network s (Autodesk InfoSewer) were converted into GIS shapefiles (referred to as “model shapefiles”).

2. Model shapefiles were updated with invert elevations and slope data if it was available in the City’s current Sewer GIS information.

3. Recently constructed or replacement sewers , not currently in the City’s Sewer GIS information or included in the previous model, were incorporated into the model shapefiles using as-built plans.

4. The model shapefiles were reviewed by the City and then revised based on City comments.

5. Finalized model shapefiles were imported into the Aquatwin Sewer model software. 6-3.2 Invert Elevation Datum Adjustment
Initially, the pipe invert elevations were not all relative to one another, likely due to datum differences between source datasets. When running the Aquatwin Sewer model, the pipe invert elevations must be relative to one another to run properly. Upstream pipes must always have inverts higher than downstream pipes. If not, it will cause the model to incorrectly simulate surcharged or pressurized conditions. Therefore, some pipe inverts were adjusted to ensure continuity between adjacent pipes. The original pipe slopes were always maintained when adjusting inverts. As a result of the invert elevation adjustments, model invert elevations may differ from survey data, as-built drawings, or GIS records.
6-3.3 Model Geometry Provision
Previous Sewer Master Plan reports were reviewed but the origin of the hydraulic model data is not absolutely clear. The 2006 Combined Central Anaheim Area Master Plan of Sanitary Sewers report (CH2MHILL) states that GIS data was used to develop the model and missing data was input manually. It is assumed that the model inverts were based on review of as-built plans.

The 2017 Central Anaheim Master Plan of Sanitary Sewers report (Psomas) states that the model was “checked for accuracy and adjustments in datums made to sewer invert elevations”. Pipeline improvements constructed after the 2006 work was completed were added to the model.

HYDRAULIC MODEL
CITY OF ANAHEIM 6-3 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
As previously stated, hydraulic models prepared for the Central Anaheim Sewer Master Plan (2017) and the West Anaheim Sewer Master Plan (2019) were used as the basis of the updated model. Additional sewer pipes constructed after the 2017 work was completed, were added to the model based on as-built plans.

The City’s hydraulic model is now the result of three master plan projects , and includes improvements to the model geometry over the 20 years, including but not limited to, as -built plan review, field surveys, and flow monitoring. The model results are an initial planning level evaluation of the system capacity . I mprovement projects should be implemented only upon a detailed review of the pipe inverts, slopes, and capacities based on further investigation of as-built plans, flow monitoring, surveying, and/or closed -circuit television (CCTV) inspections.
6-4 Split Manholes
The Central Anaheim service area contains 69 split manholes, defined as manholes with two outlet pipes.

The locations of the split manholes were confirmed through plan review and/or field survey. Generally, the model was set up to split the flows based on the existing pipe sizes and invert elevations for all scenarios . The split manhole locations are shown on Figure 3- 2 and
detailed in Table 6-1
Some of the split manholes had a direct effect on model calibration and the overall system analysis. The
operations of these locations were not always set up the same for each model scenario. These split manhole
locations were evaluated in greater detail and are
discussed in this section of the report.

Split Manholes at Harbor Boulvard and Katella Avenue:

As shown on Figure 6-1, flow in the pipe on the east side of Harbor Boulevard can split west and south at Manhole SW087319; however, field surveys confirmed that all flow is currently diverted south by a block within the manhole.

At Manhole SW076431, flow is split west and southwest
by invert elevations, and at Manhole SW076424, flow is
split west and northwest . In the model, these split
manholes were set up to operate in the same manner for
the calibration, existing, and future scenarios.

Figure 6-1
Split Manholes at Harbor Boulevard
and Katella Avenue

HYDRAULIC MOCEL

CITY OF ANAHEIM 6-4 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table 6-1
Split Manhole Summary

No. Location
Pipe
Size (in)
Normal Flow
Direction
Overflow
Direction1 No. Location
Pipe
Size (in)
Normal Flow
Direction
Overflow
Direction1
12 Southeast - 15 South -
12 Southeast 24 West
15 Southwest - 21 South -
24 South 18 West
12 West - 15 Southwest -
15 North 18 West
24 South - 15 South -
24 West 10 Southwest
24 South - 21 Block to
the west
27 West 15 South -
24 West - 8 South -
24 Northwest 12 West
24 West 12 West -
8 South 12 South
8 West 6 West -
8 South 12 South
8 West - 8 South -
8 East 8 Northwest
6 West - 18 South -
6 Northwest 18 West
8 South - 21 South -
8 West 10 West
24 South - 8 North
33 West 8 West
24 West - 6 South -
8 Northwest 6 West
24 West - 8 West
8 Southwest 6 East
8 North - 8 South -
8 South 8 West
6 East - 8 North -
6 North 8 South
12 West - 8 East -
10 South 8 West
10 South - 12 North -
10 West 8 South
10 North 21 East
8 West 18 West
12 West - 8 West High point
6 South 8 South
6 North - 8 East
8 West 8 West
6 West - 30 West
6 North 15 South
15 South - 12 North
24 West 8 West
8 Northwest - 12 North -
24 West 8 West
21 West - 8 North -
8 Southwest 8 West
8 North - 8 South -
8 South 8 West
10 West - 8 North -
12 South 12 West
6 West - 8 West
8 South 8 South
8 North - 24 West
8 West 8 South
6 South - 24 West
8 West 8 South
6 West - 24 West
8 South 8 South
8 South - 8 South -
6 West 12 West
12 West 24 Northwest -
12 South 30 West
24 South 15 South -
8 West 12 West
21 South -
15 West
1 Overflow direction will only convey flow when depth of flow increase significantly during emergency conditions. 64 Wakefield ave and
Jacalene Ln
67 Westport Dr and Reseda
St
65 Wakefield Ave and
Janette Ln
66 Wakefield Ave and Gail
Ln
69 Orangewood Ave, east of
State College Blvd
59 Underhill Ave and
Sunkist St
60 Elsiena Way and
Shakespeare St
61 Dutch Ave and
Plantation Pl
62 Ward Ter and Sunkist St
63 Jackson Ave and
Armando St
54 Katella Ave and State
College
55 North of Orangewood
and Orange Center
56 East of Oshkosh Ave
and Clay St
57 Howell Ave and State
College Blvd
58 Sunkist St and
Sycamore St
49 East of Broadway and
Ash St
50 Darian Rd and Sarah
Way
51 North of Jason Dr and
Sarah Way
52 West of Clifpark Way
and McCloud St
53 State College Blvd and
Almont Ave
44 Santa Ana St and
Archison St
45 South St and East St
46 Orangewood Ave and
Mountain View Ave
47 Donacy Way and
Canfield Ln
48 North of Cedar St and
Spruce Dr
32 North of S Olive St and
E Santa Ana St
33 Water St and Olive St
34 Lemon St and South St
35 Vermont Ave and
Lemon ST
36 Vermont Ave and Lemon
ST
37 Ball Rd and Lemon St
38 Manchester Ave and
Harbor Blvd
39 Disney Way and Ahrbor
B lvd
40 Katella Ave and Harbor
B lvd
41 Katella Ave and
Clementine St
42 South of Katella Ave and
Harbor Blvd
43 North Santa Ana St and
Kroeger St
27 La Palma Ave and Patt
St
28 North of S Atchison St
and E Broadway
29 South of Melrose St
and Broadway
30 Elm St and Lemon St
31 Santa Ana St and
Lemon St
22 Vermont Ave and
Harbor Blvd
23 West St and Katella
A ve
24 Katella Ave and Harbor
B lvd
25 W Katella Ave and S
Harbor Blvd
26 South of Commercial St
and Olive St
17 North St and Harbor
B lvd
18 South of Center St
Prom. and Clementine
19 Santa Ana St and
Janss St
20 Helena St and Elm St
21 Harbor Blvd and
Hampshire Ave
12 Ball Rd and Walnut St
13 Katella Ave and Disney
Dr
14 Katella Ave and Disney
Dr
15 South of Commercial St
and Anaheim Blvd
16 Champion at Mann
Elementary School
68 1200 S Euclid St,
Anaheim, CA 92802
1 Orangewood Ave and
Spinnaker St
2 Walnut St and Cerritos
A ve
3 East St and La Palma
A ve
4 Katella Ave and 9th St
5 Katella Ave and 9th St
6 Katella Ave and 9th St
7 Wakefiled and 9th St
8 Orangewood Ave and
9th St
9 Alley west of La Verne
St and Pine St
10 Wedgewood Dr and
Birchmont Dr
11 Locus Ave and Aspen
St

HYDRAULIC MODEL

CITY OF ANAHEIM 6-5 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Split Manholes at Disneyland Drive/West Street and
Katella Avenue: As shown on Figure 6-2, flow in the pipe on the south side of Katella Avenue can split west and
south at Manhole SW076302. During the calibration
period, the flow at Manhole SW076302 was blocked to
the south. Therefore, in the calibration scenario, this manhole was modeled with all flow diverted west on
Katella Avenue. For the existing and future scenarios, flows were distributed based on invert elevations
assuming the block would be removed.

At Manhole SW066424, flow is split west and southwest,
while at Manhole SW066417, flow is split west and
northwest. In the model, these split manholes were set up to operate in the same manner for the calibration,
existing, and future scenarios.

Split Manholes at Ninth Street and Katella Avenue: As
shown on Figure 6-3, flow in the pipe on the north side of Katella Avenue can split west and south at Manhole
OT057445. At this location, flows in the model were
distributed based on invert elevations for the calibration, existing, and future scenarios.

Flow in the pipe on the south side of Katella Avenue can split west and south at Manhole OT057444. Currently,
all flow is directed south. In the model, this split manhole was set up to operate in the same manner for the
calibration, existing, and future scenarios. The City is currently working on the design of Katella Avenue
sewers to accommodate future flows associated with
development and redevelopment in the resort area (i.e.

Disneyland Theme Park area). The split manholes in
Katella Avenue were evaluated as part of the Anaheim
Resort Area Sanitary Sewer Study Final Preliminary
Design Report, dated May 2025. Per this study, the
future flows at Manhole OT05744 are planned to be
redirected west to Katella Avenue to provide additional capacity to the sewers located in Ninth Street.

At Manhole SW057450, flow can split west and
northwest. At this location, flows in the model were
distributed based on invert elevations for the calibration, existing, and future scenarios.

Split Manholes at Cerritos Avenue and Walnut Street: As shown in Figure 6-4, flow in the Walnut Street sewer can currently split to the southwest and south at Manhole 22. During the calibration period, all flow at MH 22 was diverted to the south to isolate the flows from within the resort area. Therefore, the calibration scenario was set up to divert all flows south at MH 22.

Figure 6-2
Split Manholes at Disneyland
Drive/West Street and Katella Avenue
Figure 6-3
Split Manholes
at Ninth Street and Katella Avenue

HYDRAULIC MODEL
CITY OF ANAHEIM 6-6 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Flows in the model were distributed based on invert
elevations for the existing scenarios. The City is
currently designing pipes improvements in Cerritos
Avenue such that all flow tributary to MH OT065317 will typically be diverted to the west, for the future model scenarios.

Split Manholes at Ball Road and Walnut Street : As
shown in Figure 6-5, flow at Manhole SW064426 may
split to the south on Walnut Street and to the west on
Ball Road. During the calibration period, all flow was diverted to the west to isolate the flows between the
sewer tributary areas. The existing and future system
analyses, the flows were distributed based on invert
elevations.

Split Manholes Manchester Avenue and Harbor
Boulevard As shown in Figure 6-6, the flow at Manhole SW086326 may be diverted to the western or eastern
pipe on Harbor Boulevard. In the model, this manhole
was set up to flow based on invert elevations for the
calibration, existing, and future scenarios. In the future, as the development and redevelopment projects increase the flows in these areas, the City may consider diverting flows at this manhole to maximize the existing capacities of the western and eas tern pipes in Harbor Boulevard. Future connections for new developments should also be evaluated at that time.

Figure 6-4
Split Manholes
at Cerritos Avenue and Walnut Street
Figure 6-5
Split Manholes
at Ball Road and Walnut Street

Figure 6-6
Split Manholes at Manchester Avenue and
Harbor Boulevard

HYDRAULIC MODEL
CITY OF ANAHEIM 6-7 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
6-5 Siphons
There are 75 siphons in the existing system as described in Section 3-3. It should be noted that the model is not set up to include a detailed hydraulic analysis of the siphons. The model software calculates an average slope using the inverts at the upstream and downstream end of each siphon. The hydraulic analysis results are based upon this calculated average slope.

Whenever a siphon is in need of replacement or if a new siphon is being designed, a detailed hydraulic analysis should be performed during the preliminary design phase of the project to size the siphon and determine the hydraulic grade lines in the adjacent portions of the system. 6-6 Model Calibration – Dry Weather Scenario
The hydraulic model was calibrated through an iterative process that incorporated updates to the model geometry based on as -built plans and field survey data, as well as refinements to sewer loads, sewer return factors, and diurnal flow patterns to align with flow monitoring results. The calibration effort was performed for a dry weather weekday representing peak dry weather flow conditions, with the understanding that the timing and magnitude of peak flows may vary across the system. Model accuracy was ass essed by comparing the model results to flow data at each flow monitoring location.

To isolate the flows between sewer flow monitoring locations, blocks were placed at the following flow split locations:
 Ball Road and Walnut Street (Manhole ID: SW064426) – All flow was diverted west on Ball Road  Cerritos Avenue and Walnut Street (Manhole ID: 22) – All flow was diverted south on Walnut Street  West Street and Katella Avenue (Manhole ID: SW076302) - All flow was diverted west on Katella Avenue
 Harbor Blvd and Katella Avenue (Manhole ID: SW087319) – All flow was diverted to the south sewer on Katella Avenue
A comparison of the measured flows and model calculated flows is provided in Table 6-2. Comparison graphs of measured flows and model calculated flows for the calibration period are shown on Figures 6-7 to 6-10. The calibration effort was based on flow monitoring data collected by ADS Environmental Services. This dataset was considered the most reliable for calibration purposes due to the fact that both depth and velocity were measured within the pipe in order to calculate flow. Data from SmartCover devices, which estimate flow solely based on depth measurements within the manhole channels, were reviewed for reasonableness but were not used for calibration purposes.

At Site ADS 9, the peak flow in the model is about 13% higher than the peak flow measured. This is conservative but acceptable for planning purposes.

At Site ADS 10 and ADS 11, the peak flow in the model is about 8% and 1% lower than the peak flow measured, respectively. This is acceptable for planning purposes.

Sites ADS 13 and ADS 14 are located on parallel sewers in Katella Avenue, west of Walnut Street. Individually, the flows at these sites do not match as well as when the flows are combined. The model calculates more flow at Site ADS 13 and less flow at Site ADS 14 than what was measured in the field. There are several flow splits upstream of Site ADS 13 and ADS 14. Flow can move between the north and south sewers in Katella Avenue.

The exact split of flows at each split manhole was difficult to calibrat e precisely. The City is currently working on the design of Katella Avenue sewers to accommodate future flows associated with development and redevelopment in the resort area (i.e. Disneyland Theme Park area). The split manholes in Katella Avenue will be further evaluated as a part of this project.

HYDRAULIC MODEL

CITY OF ANAHEIM 6-8 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table 6-2
Comparison of Measured Flows and Model Calculated Flows

Average Maximum Average Maximum Average Maximum
ADS 9 SW114329 SW114330-
SW114329
Wagner Ave, east of
State College Blvd 3/11/24 0.5895 0.9600 0.5419 1.0887 8.1% 13.4% ADS 10 SW052204 SW052205-
SW052204
La Palma Ave, east of
Laguna St 4/16/24 1.3978 2.1310 1.3702 1.9602 2.0% 8.0% ADS 11 SW055334 OT055336-
OT055334 Ball Rd, west of Loara St 4/18/24 4.9759 7.0010 4.9078 6.9389 1.4% 0.9% ADS 131,2 SW066329 OT066331-
OT066329
Katella Ave, east of 9th St
(north sewer) 4/3/24 2.3352 3.1590 2.2938 3.6586 1.8% 15.8% ADS 141,2 SW066327 SW066328-
SW066327
Katella Ave, east of 9th St
(south sewer) 4/3/24 1.6803 2.5360 1.7870 2.1399 6.3% 15.6% ADS 13 &
ADS141,2
See sites
13 and 14
See sites 13
and 14 Katella Ave, east of 9th St 4/3/24 3.9918 5.6170 4.0808 5.7985 2.2% 3.2% 1 Sites 13 and 14, representing the north and south sewers in Katella Avenue. Total flow was evaluated due to multiple flow splits in the upstream system. % Difference
Comments
Measured Flow 4
(MGD)
Model Calibration
Flow
(MGD)
2 Block s placed in the manhole at Ball Rd/Walnut St (diverted flow west of Ball Rd), Katella Ave/West St (diverted flow west in Katella Ave), and at Walnut St/Cerritos St (diverted flow south in West St) to isolate flows between flow monitoring locations. 4 Measured flow based on flow monitoring data collected during calibration period and does not match the average flows detailed in Table 4-1.

Calibration of total flow to Site
13 and 14 matches well. The
allocation of the future loads
between the north and south
sewers are being evaluated as
part of the Katella Avenue
sewer improvement projects,
currently in the design stage.

Calibration
Date3
3 Separate calibration dates were selected to represent the hightest peak flow for each area as they occurred on different dats.

Flow
Monitor
Site
ID
Model
Manhole
ID
Model Pipe
ID Location

HYDRAULIC MODEL

CITY OF ANAHEIM 6-9 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Figure 6-7
Dry Weather Model Calibration
ADS Flow Monitoring Site 9 (Wagner Avenue)

Figure 6-8
Dry Weather Model Calibration
ADS Flow Monitoring Site 10 (La Palma Avenue)

0.00 0.20

0.40 0.60

0.80 1.00

1.20 12:00 AM
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7:00 PM
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10:00 PM
11:00 PM
12:00 AM
Flow (mgd)
Time
Flow Monitoring
Model Results

0.00 0.20

0.40 0.60

0.80 1.00

1.20 1.40

1.60 1.80

2.00 2.20

2.40 12:00 AM
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Flow (mgd)
Time
Flow Monitoring
Model Results

HYDRAULIC MODEL
CITY OF ANAHEIM 6-10 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Figure 6-9
Dry Weather Model Calibration
ADS Flow Monitoring Site 11 (Ball Rd)

Figure 6-10
Dry Weather Model Calibration
ADS Flow Monitoring Site 13/14 (Katella Avenue)

0.00 0.50

1.00 1.50

2.00 2.50

3.00 3.50

4.00 4.50

5.00 5.50

6.00 6.50

7.00 7.50
12:00 AM
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Flow (mgd)
Time
Flow Monitoring
Model Results

0.00 0.50

1.00 1.50

2.00 2.50

3.00 3.50

4.00 4.50

5.00 5.50

6.00 6.50
12:00 AM
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Flow (mgd)
Time
Flow Monitoring
Model Results

HYDRAULIC MODEL
CITY OF ANAHEIM 6-11 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
6-7 Model Calibration - Wet Weather Scenario
The wet weather scenario was developed to evaluate the existing system under the wet weather conditions captured during the Sewer Master Plan flow monitoring period. The rainfall dependent inflow and infiltration (RDII) evaluation is discussed in detail in Section 4-7.

The wet weather scenario was based on flow monitoring data collected during the 2/4/24 - 2/6/24 storm event.

The model was updated to represent the 24- hour period of February 6, 2024, which captured the peak wet weather flows. This storm produced 4.8 inches of rainfall over 54 hours which represents a 5- to 10-year storm frequency.
6-7.1 RDII Loads and Diurnal Patterns
It was previously stated in Section 4- 7 that the wet weather flow at ADS Site 9 is believed to have been underestimated during the 2/4/24-2/6/24 storm. Therefore, the data at ADS Site 9 was not utilized for the wet weather scenario. RDII was estimated for the remaining ADS Sites by calculating the difference between the wet weather flow that was measured on February 6, 2024 and the typical average weekday flow over a 24-hour period. The number of manholes upstream of each flow monitoring site was identif ied and the total RDII was then distributed equally to each manhole in the sewer model. The average RDII per manhole calculated for the flow monitoring sites was applied to the remaining areas that were not located within one of the flow monitoring tributary areas. The total RDII load added to the model was 6.17 MGD.

Diurnal flow patterns were developed at each flow monitoring site as shown in Figure 6-11 and then applied to the manholes in the applicable basin. The average diurnal pattern was applied to all manholes that were not located within one of the flow monitoring tributary areas.

Figure 6-11
RDII Diurnal Patterns

HYDRAULIC MODEL
CITY OF ANAHEIM 6-12 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
6-7.2 Measured Flows versus Model Flows
The RDII diurnal patterns were iteratively adjusted to match flow monitoring data peaks during the wet weather event. Similar to the dry weather calibration effort, the wet weather calibration effort was based on flow monitoring data collected by ADS Environmental Services. This dataset was considered the most reliable for calibration purposes due to the fact that both depth and velocity was measured within the pipe in order to calculate flow.

The peak flow simulated in the model closely matched the peak measured flows during the wet weather event on 2/6/24 as shown on Figures 6-12 through 6-14.

Figure 6-12
Wet Weather Model Calibration
ADS Flow Monitoring Site 10 (La Palma Avenue)

0.00 0.50

1.00 1.50

2.00 2.50

3.00 3.50
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HYDRAULIC MODEL
CITY OF ANAHEIM 6-13 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Figure 6-13
Wet Weather Model Calibration
ADS Flow Monitoring Site 11 (Ball Rd)

Figure 6-14
Wet Weather Model Calibration
ADS Flow Monitoring Site 13/14 (Katella Avenue)

0.00 1.00

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HYDRAULIC MODEL
CITY OF ANAHEIM 6-14 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
6-8 Model Scenarios
Five (5) model scenarios were developed for the Sewer Master Plan study: Dry Weather Calibration, Wet Weather Calibration, Dry Weather Existing Condition, Wet Weather Existing Condition and Dry Weather Future Condition.

The process of developing the sewer loads for the calibration, existing and future conditions is discussed in Section 5, Sewer Loads. Generally, the sewer loads of each model scenario are as follows:

3. Future Condition Scenario: Future loads are the existing condition loads plus increases in loads where new development/redevelopment is planned or densification is expected, specifically in the following locations:
 Theme Park Expansion
 Anaheim Convention Center Expansion
 Anaheim Garden Walk Expansion
 Public Facilities Expansion – Civic Center, Police Department, Fire Department  General Plan Redevelopment Areas
 Accessory Dwelling Units (ADUs) in Low Density Residential Areas The calibrated loads are utilized for all three model scenarios for any portion of the service area that is not located near a major attraction or event center and is not expected to change landuse or densify in the future.

The dry weather diurnal patterns shown on Figure 4-3 were applied to all dry weather loads. The RDII diurnal patterns shown on Figure 6-11 were applied to the RDII loads. The total average sewer loads for each model scenario are summarized in Table 6-3. Hydraulic analysis and results are presented in Section 7.

Table 6-3
Sewer Model Scenario Loads

Scenario
Average Sewer
Load (MGD)
Dry Weather Calibration 18.3
Wet Weather Calibration 24.4
Dry Weather Existing Condition 20.1
Wet Weather Existing Condition 26.3
Dry Weather Future Condition 30.5

CITY OF ANAHEIM 7-1 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
SECTION 7

CAPACITY ANALYSIS
7-1 General
A hydraulic model was developed to assess the capacity of the existing sewer system to convey existing and future estimated flows. The development of the model is described in Section 6, while the criteria used to evaluate gravity system capacity and summary of the results are presented in this section of the report. 7-2 Criteria
Establishing performance standards is an important part of evaluating the existing sewer collection system, as it forms the basis for the system improvement recommendations. Collection system design standards include minimum pipe size, minimum slope, and maximum depth of flow to pipe diameter ratio (d/D). 7-2.1 Minimum Pipe Size
Per the City’s 2023 Sewer Design Manual, the minimum pipe size shall be 8- inches in diameter unless otherwise noted and approved.
7-2.2 Pipe Slope
Per the City’s 2023 Sewer Design Manual, the minimum velocity is 2 ft/s and the minimum slopes for sewers to achieve this minimum self-cleaning velocity for the expected design flow are shown in Table 7-1. Maximum slopes shall not exceed 10% or 0.1000.

It is recognized that the desired minimum slopes and velocities are sometimes not achievable under certain circumstances. On a case by case basis, the City may approve sewer designs that do not meet these criteria. More frequent pipe cleaning may be needed in areas with less than the minimum slopes
shown in Table 7- 1, where velocities are
less than the minimums recommended,
and/or further reduction in inside water use
results in increased solids deposition in the
pipelines.
7-2.3 Maximum Depth to Diameter
Ratio
The design and analysis of sewer pipes is
based upon the depth to diameter ratio
(d/D) with peak dry weather flow.

Assuming a constant Manning roughness
coefficient and slope of a circular pipe, the
velocity and flow rate profiles can be
plotted against the depth of flow as shown
on Figure 7 -1. The maximum velocity
occurs at about 81.3 percent full
(d/D=0.813). The maximum flow rate
Figure 7-1
Pipe Size (in) Minimum Slope
8" 0.0036
10" 0.0030
12" 0.0024
15" and larger 0.0020
Table 7-1
Minimum Sewer Slopes

CAPACITY ANALYSIS
CITY OF ANAHEIM 7-2 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
occurs at about 93.8 percent full (d/D=0.938). Although the maximum flow rate exceeds that of a full pipe by about 8 percent, the difference is somewhat insignificant since pipes operating near full capacity tend to experience slightly unstable flow. The flow rate at about 0.82 is therefore commonly considered the maximum capacity because it has the same capacity as when the pipe is full.

Sewer agencies set d/D criteria to provide enough capacity in the system to avoid backups and sewer spills.

At the same time, minimum velocities must be considered so as not to allow debris to settle and create septic conditions that could potentially become a continual operation and maintenance issue. It is also not practical or feasible to size the pipes in a system to convey an excessive amount of wet weather flow.

Per the City’s 2023 Sewer Design Manual, t he following depth to diameter (d/D) criteria were applied for evaluating the capacity of the existing and future sewers:

1. For existing pipes:
a. 10-inch and smaller sewers: d/D = 0.67 with peak dry weather flows b. 12-inch and larger sewers: d/D = 0.75 with peak dry weather flows

2. For new construction or future planned sewers:
a. 10-inch and smaller sewers: d/D = 0.50 with peak dry weather flows b. 12-inch and larger sewers: d/D = 0.60 with peak dry weather flows The remaining pipe capacity is reserved within the sewer pipes to accommodate wet weather flows. 7-3 Gravity Sewer Dry Weather Flow Analysis1 Existing Sewer Loads 7-3.1 Existing Capacity Deficiencies
The existing capacity deficiencies, based upon the established criteria and the hydraulic model, were found to be limited to one sewer pipe with a total length of 85 feet. It is a minor deficiency in an existing 8-inch pipe, located near the Anaheim Convention Center on West Street. The hydraulic deficiencies are listed in Table 7- 2 and shown on Figure 7-2.

The City’s proactive approach to sewer system management has significantly strengthened the performance of its collection system. Since the completion of the 2017 Central Anaheim Sewer Master Plan, the City has successfully implemented a series of capacity improvement projects . This is the primary reason for the limited amount of existing capacity deficiencies. The City has also been rehabilitating aging sewer pipelines through an ongoing pipe lining program since 2007. Pipe lining locations are shown on Figure 3 -2. These efforts demonstrate the City’s continued commitment to maintaining reliable infrastructure and protecting public health and the environment.
7-3.2 Future Capacity Deficiencies
The capacity deficiencies associated with the addition of future development and redevelopment sewer loads are shown in Table 7-2 and on Figure 7-2. The total length of existing sewers found to be capacity deficient is 24,622 feet. This is 1.9 % (24,622 / 1,323, 527 ft) of the total existing system length in the Central Anaheim service area. The analysis is based on future load projections using the best available planning data, as detailed in Section 5- 5. As more detailed planning data is finalized , the sewer capacities should be reassessed.

CAPACITY ANALYSIS

CITY OF ANAHEIM 7-3 Central Anaheim Sewer Master Plan
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Table 7-2
Existing and Future Capacity Deficiencies

ADWF
(mgd)
PDWF
(mgd)

Depth
(ft)

Depth
(in)
PDWF
d/D
ADWF
(mgd)
PDWF
(mgd)

Depth
(ft)

Depth
(in)
PDWF
d/D
1 Existing SW077111-SW067222 SW077111 SW067222 8 85 0.0057 0.013 0.3266 0.5206 0.47 5.60 0.70 0.5122 0.8189 0.64 7.68 0.96 85 1 Future SW067222-SW067406 SW067222 SW067406_A 10 319 0.0045 0.013 0.3274 0.5180 0.42 5.10 0.51 0.5129 0.8136 0.57 6.80 0.68 SW096304-SW096303 SW096304 SW096303 8 352 0.0030 0.013 0.0053 0.0066 0.07 0.80 0.10 0.2942 0.3763 0.56 6.72 0.84 SW096303-SW096302 SW096303 SW096302 8 349 0.0028 0.013 0.0060 0.0075 0.06 0.72 0.09 0.3493 0.4504 0.57 6.80 0.85 SW096302-SW096305 SW096302 SW096305 10 368 0.0024 0.013 0.0643 0.0804 0.18 2.20 0.22 0.5025 0.7050 0.77 9.30 0.93 SW096301-SW096302 SW096301 SW096302 8 145 0.0044 0.013 0.0582 0.0727 0.16 1.92 0.24 0.1533 0.2753 0.45 5.36 0.67 SW096116-SW096304 SW096116 SW096304 8 310 0.0029 0.013 0.0034 0.0042 0.05 0.64 0.08 0.2289 0.2946 0.45 5.44 0.68 SW096311-SW096310 SW096311 SW096310 8 358 0.0024 0.013 0.0175 0.0219 0.11 1.36 0.17 0.2103 0.3940 0.67 8.00 1.00 SW096307-SW096305 SW096307 SW096305 8 361 0.0024 0.013 0.0229 0.0286 0.12 1.44 0.18 0.3464 0.6500 0.57 6.88 0.86 CO097104-SW096310 CO097104 SW096310 8 73 0.0020 0.013 0.0036 0.0045 0.08 0.96 0.12 0.0005 0.1053 0.67 8.00 1.00 SW096309-SW096308 SW096309 SW096308 8 176 0.0029 0.013 0.0229 0.0286 0.12 1.44 0.18 0.3443 0.6449 0.67 8.00 1.00 SW096310-SW096309 SW096310 SW096309 8 177 0.0029 0.013 0.0211 0.0264 0.11 1.36 0.17 0.3362 0.6287 0.67 8.00 1.00 SW096308-SW096307 SW096308 SW096307 8 344 0.0024 0.013 0.0229 0.0286 0.13 1.60 0.20 0.3443 0.6459 0.67 8.00 1.00 SW097201-SW097101 SW097201 SW097101 8 444 0.0020 0.013 0.0007 0.0009 0.05 0.64 0.08 0.0293 0.2119 0.67 8.00 1.00 SW097101-SW096311 SW097101 SW096311 8 32 0.0022 0.013 0.0075 0.0093 0.07 0.80 0.10 0.2104 0.3864 0.67 8.00 1.00 SW117304-SW117303 SW117304 SW117303 10 261 0.0038 0.013 0.0418 0.0522 0.13 1.60 0.16 0.7859 1.3872 0.83 10.00 1.00 SW117411-SW117409 SW117411 SW117409 10 93 0.0043 0.013 0.0236 0.0295 0.10 1.20 0.12 0.2240 0.5329 0.83 10.00 1.00 SW117409-SW117408 SW117409 SW117408 10 211 0.0029 0.013 0.0397 0.0497 0.16 1.90 0.19 0.6563 1.1551 0.83 10.00 1.00 SW117408-SW117405 SW117408 SW117405 10 139 0.0019 0.013 0.0400 0.0499 0.15 1.80 0.18 0.6612 1.1638 0.83 10.00 1.00 SW117405-SW117404 SW117405 SW117404 10 135 0.0053 0.013 0.0413 0.0516 0.14 1.70 0.17 0.7460 1.3153 0.83 10.00 1.00 SW117404-SW117304 SW117404 SW117304 10 304 0.0027 0.013 0.0413 0.0516 0.15 1.80 0.18 0.7460 1.3168 0.83 10.00 1.00 SW117303-SW117302 SW117303 SW117302 10 120 0.0056 0.013 0.0429 0.0537 0.11 1.30 0.13 0.7859 1.3875 0.62 7.40 0.74 SW117412-SW117411 SW117412 SW117411 10 107 0.0037 0.013 0.0236 0.0295 0.10 1.20 0.12 0.1937 0.4708 0.83 10.00 1.00 SW117416-SW117409 SW117416 SW117409 8 158 0.0016 0.013 0.0100 0.0125 0.09 1.04 0.13 0.4323 0.7818 0.67 8.00 1.00 SW117209-SW117403 SW117209 SW117403 8 247 0.0036 0.013 0.0191 0.0239 0.11 1.28 0.16 0.1753 0.4098 0.67 8.00 1.00 SW117403-SW117412 SW117403 SW117412 8 225 0.0039 0.013 0.0214 0.0267 0.11 1.28 0.16 0.1806 0.4134 0.67 8.00 1.00 SW117205-SW117209 SW117205 SW117209 8 378 0.0039 0.013 0.0174 0.0218 0.10 1.20 0.15 0.1458 0.3924 0.67 8.00 1.00 SW117206-SW117205 SW117206 SW117205 8 292 0.0032 0.013 0.0136 0.0170 0.09 1.12 0.14 0.1195 0.2842 0.67 8.00 1.00 SW127103-SW117204 SW127103 SW117204 8 299 0.0032 0.013 0.0089 0.0112 0.07 0.88 0.11 0.0757 0.2173 0.67 8.00 1.00 SW117204-SW117206 SW117204 SW117206 8 286 0.0034 0.013 0.0110 0.0137 0.09 1.04 0.13 0.0887 0.2372 0.67 8.00 1.00 SW117401-SW117405 SW117401 SW117405 10 218 0.0039 0.013 0.0013 0.0017 0.02 0.30 0.03 0.0362 0.1900 0.83 10.00 1.00 SW117208-SW117402 SW117208 SW117402 8 393 0.0039 0.013 0.0013 0.0017 0.03 0.32 0.04 0.0356 0.1040 0.67 8.00 1.00 SW117402-SW117401 SW117402 SW117401 8 84 0.0052 0.013 0.0013 0.0017 0.03 0.32 0.04 0.0358 0.1909 0.67 8.00 1.00 SW096305-SW086411 SW096305 SW086411 12 135 0.0057 0.013 0.0875 0.1094 0.20 2.40 0.20 0.8595 1.3380 1.00 12.00 1.00 SW086411-SW086409 SW086411 SW086409 12 284 0.0024 0.013 0.1089 0.1361 0.24 2.88 0.24 0.8882 1.3834 1.00 12.00 1.00 SW086409-SW086408 SW086409 SW086408 12 292 0.0023 0.013 0.1089 0.1361 0.24 2.88 0.24 0.8882 1.3834 0.91 10.92 0.91 SW087302-SW087301 SW087302 SW087301 10 234 0.0031 0.013 0.1286 0.2032 0.27 3.30 0.33 0.4408 0.6961 0.57 6.90 0.69 SW087301-SW087106 SW087301 SW087106 10 219 0.0048 0.013 0.1286 0.2032 0.40 4.80 0.48 0.4408 0.6961 0.67 8.10 0.81 SW107111-SW107110 SW107111 SW107110 8 362 0.0023 0.013 0.0038 0.0047 0.05 0.64 0.08 0.1116 0.2004 0.51 6.08 0.76 SW107110-SW107109 SW107110 SW107109 8 339 0.0014 0.013 0.0078 0.0097 0.09 1.04 0.13 0.2053 0.3689 0.67 8.00 1.00 SW107109-SW107108 SW107109 SW107108 8 361 0.0035 0.013 0.0131 0.0164 0.08 0.96 0.12 0.2782 0.4998 0.54 6.48 0.81 6 Future
7 Future
3 Future
4 Future
5 Future
Roughness
Existing Conditions Future Conditions
Existing Deficiency Total
2 Future
Capacity
Deficiency
Location

Future
Capacity
Deficiency Pipe ID U/S MH ID D/S MH ID
Pipe
Diameter
(in)
Pipe
Length
(ft) Slope

CAPACITY ANALYSIS
CITY OF ANAHEIM 7-4 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table 7-2 (Continued)
Existing and Future Capacity Deficiencies

ADWF
(mgd)
PDWF
(mgd)
PDWF
Depth
(ft)
PDWF
Depth
(i
n)
PDWF
d/D
ADWF
(mgd)
PDWF
(mgd)
PDWF
Depth
(ft)
PDWF
Depth
(i
n)
PDWF
d/D
SW108208-SW108203 SW108208 S W108203 8 319 0.0024 0.013 0.0032 0.0042 0.05 0.56 0.07 0.2560 0.4739 0.67 8.00 1.00 SW108203-SW108201 SW108203 SW108201 8 318 0.0021 0.013 0.0032 0.0041 0.05 0.64 0.08 0.2560 0.4625 0.62 7.44 0.93 SW108201-SW107409 SW108201 SW107409 8 322 0.0038 0.013 0.0049 0.0068 0.09 1.12 0.14 0.2576 0.4643 0.49 5.84 0.73 SW119107-SW119106 SW119107 S W119106 8 271 0.0020 0.013 0.0069 0.0086 0.07 0.88 0.11 0.2018 0.3624 0.49 5.84 0.73 SW119108-SW119107 SW119108 S W119107 8 275 0.0020 0.013 0.0057 0.0071 0.07 0.80 0.10 0.1707 0.3072 0.51 6.08 0.76 SW119106-SW118309 SW119106 S W118309 8 277 0.0079 0.013 0.0165 0.0206 0.13 1.52 0.19 0.2488 0.4470 0.50 6.00 0.75 SW119214-SW119210 SW119214 S W119210 8 251 0.0029 0.013 0.0079 0.0099 0.10 1.20 0.15 0.2053 0.3687 0.47 5.68 0.71 SW119210-SW119206 SW119210 S W119206 8 215 0.0051 0.013 0.0079 0.0099 0.07 0.80 0.10 0.2207 0.3965 0.46 5.52 0.69 SW086311-SW087101 SW086311 S W087101 15 339 0.0020 0.013 0.5359 0.7857 0.58 6.90 0.46 1.1153 1.6883 0.95 11.40 0.76 SW087305-SW087306 SW087305 SW087306 15 333 0.0024 0.013 0.8109 1.2164 0.66 7.95 0.53 1.6213 2.1629 1.04 12.45 0.83 SW087101-SW087102 SW087101 SW087102 15 41 0.0020 0.013 0.5652 0.8314 0.60 7.20 0.48 1.1446 1.7305 0.98 11.70 0.78 SW087102-SW087103 SW087102 SW087103 15 297 0.0020 0.013 0.5950 0.8783 0.61 7.35 0.49 1.1744 1.7755 1.01 12.15 0.81 SW087103-SW087104 SW087103 SW087104 15 43 0.0020 0.013 0.6131 0.9064 0.63 7.50 0.50 1.1925 1.8008 1.04 12.45 0.83 SW087104-SW087105 SW087104 SW087105 15 291 0.0020 0.013 0.6396 0.9481 0.69 8.25 0.55 1.2190 1.8413 1.09 13.05 0.87 SW087105-SW087106 SW087105 SW087106 15 340 0.0015 0.013 0.6528 0.9671 0.61 7.35 0.49 1.2190 1.8406 0.98 11.70 0.78 SW087106-SW087304 SW087106 SW087304 15 340 0.0020 0.013 0.7814 1.1703 0.70 8.40 0.56 1.5918 2.1180 1.13 13.50 0.90 SW087304-SW087305 SW087304 SW087305 15 330 0.0024 0.013 0.7814 1.1698 0.70 8.40 0.56 1.5918 2.1167 1.08 12.90 0.86 SW102326-SW103103 SW102326 S W103132 8 358 0.0047 0.013 0.1331 0.1728 0.27 3.28 0.41 0.2221 0.4038 0.46 5.52 0.69 SW103102-SW103101 SW103102 S W103101 8 105 0.0040 0.013 0.1836 0.2369 0.31 3.68 0.46 0.2726 0.4526 0.45 5.44 0.68 SW103103-SW103102 SW103103 S W103131 8 61 0.0036 0.013 0.1370 0.1819 0.29 3.52 0.44 0.2260 0.4142 0.49 5.92 0.74 2362 SW103132 S W103103 8 57 0.0036 0.013 0.1356 0.1780 0.29 3.44 0.43 0.2245 0.4103 0.49 5.84 0.73 2364 SW103131 S W103102 8 277 0.0034 0.013 0.1389 0.1868 0.31 3.76 0.47 0.2279 0.4191 0.51 6.08 0.76 13 Future SW069402-SW069401 SW069402 S W069401 8 313 0.0021 0.013 0.0204 0.0254 0.11 1.36 0.17 0.1827 0.3282 0.45 5.44 0.68 SW087313-SW087311 SW087313 S W087311 21 126 0.0020 0.013 1.0346 1.4023 0.67 7.98 0.38 3.1389 5.0336 1.58 18.90 0.90 SW087315-SW087318 SW087315 S W087318 21 94 0.0020 0.013 0.9936 1.3377 0.65 7.77 0.37 3.0979 4.9703 1.59 19.11 0.91 SW087415-SW087414 SW087415 S W087414 21 147 0.0020 0.013 0.9677 1.2977 0.63 7.56 0.36 2.4975 4.0365 1.56 18.69 0.89 SW087414-SW087413 SW087414 S W087413 21 104 0.0020 0.013 0.9677 1.2977 0.65 7.77 0.37 2.9968 4.8209 1.61 19.32 0.92 SW087318-SW087313 SW087318 S W087313 21 116 0.0020 0.013 0.9965 1.3421 0.67 7.98 0.38 3.1008 4.9742 1.59 19.11 0.91 SW087311-SW087309 SW087311 S W087309 21 213 0.0020 0.013 1.0502 1.4269 0.70 8.40 0.40 3.1547 5.0577 1.54 18.48 0.88 SW087417-SW087416 SW087417 S W087416 21 56 0.0020 0.013 0.7117 0.8937 0.61 7.35 0.35 1.8161 3.0073 1.45 17.43 0.83 SW087416-SW087415 SW087416 S W087415 21 15 0.0020 0.013 0.9662 1.2954 0.63 7.56 0.36 2.4912 4.0303 1.51 18.06 0.86 SW087413-SW087425 SW087413 S W087425 21 90 0.0020 0.013 0.9883 1.3304 0.65 7.77 0.37 3.0875 4.9617 1.61 19.32 0.92 SW087317-SW087315 SW087317 S W087315 21 124 0.0020 0.013 0.9901 1.3322 0.65 7.77 0.37 3.0944 4.9660 1.59 19.11 0.91 SW087425-SW087317 SW087425 S W087317 21 239 0.0020 0.013 0.9896 1.3322 0.65 7.77 0.37 3.0931 4.9675 1.61 19.32 0.92 Roughness
Existing Conditions Future Conditions
Pipe ID U/S MH ID D/S MH ID
Pipe
Diameter
(i
n)
Pipe
Length
(ft) Slope
14 Future
Capacity
Deficiency
L
ocation
Existing or
Future
C
apacity
Deficiency
10 Future
Harbor Future
12 Future
8 Future
9 Future

CAPACITY ANALYSIS
CITY OF ANAHEIM 7-5 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table 7-2 (Continued)
Existing and Future Capacity Deficiencies
ADWF
(mgd)
PDWF
(mgd)

Depth
(ft)

Depth
(in)
PDWF
d/D
ADWF
(mgd)
PDWF
(mgd)

Depth
(ft)

Depth
(in)
PDWF
d/D
SW076427-SW076417 SW076427 SW076417 21 449 0.001853 0.013 0.8571 1.4422 0.68 8.19 0.39 2.9755 4.2043 1.75 21.00 1.00 SW076410-SW076409 SW076410 SW076409 24 159 0.001973 0.013 1.4758 1.9260 0.74 8.88 0.37 3.7180 6.3761 1.62 19.44 0.81 SW066424-SW066417 SW066424 SW066417 8 20 -0.03818 0.013 0.0000 0.0000 0.15 1.76 0.22 0.1491 0.4639 0.59 7.12 0.89 SW066332-OT066331 SW066332 OT066331 24 25 0.001853 0.013 1.9444 2.9716 1.16 13.92 0.58 4.7178 6.6176 2.00 24.00 1.00 SW066417-SW066428 SW066417 SW066428 8 19 0.071615 0.013 0.0000 0.0000 0.33 4.00 0.50 0.2308 0.5290 0.59 7.12 0.89 SW076310-SW076309 SW076310 SW076309 21 249 0.001853 0.013 1.0800 1.7893 0.77 9.24 0.44 3.4664 4.9200 1.75 21.00 1.00 SW076312-SW076311 SW076312 SW076311 21 374 0.001853 0.013 1.0790 1.7897 0.77 9.24 0.44 3.4651 4.9201 1.75 21.00 1.00 SW076417-SW076312 SW076417 SW076312 21 384 0.001853 0.013 0.8587 1.4420 0.74 8.82 0.42 2.9775 4.1833 1.75 21.00 1.00 SW076411-SW076424 SW076411 2056 24 44 0.002406 0.013 1.9219 2.7235 0.84 10.08 0.42 4.8370 7.3129 1.66 19.92 0.83 SW076433-SW076308 SW076433 SW076308 24 379 0.001973 0.013 1.7288 2.3254 0.84 10.08 0.42 3.9712 6.7512 1.76 21.12 0.88 SW076430-SW076429 SW076430 SW076429 21 267 0.001816 0.013 0.8560 1.4423 0.67 7.98 0.38 2.9736 4.2623 1.75 21.00 1.00 SW087307-SW076411 SW087307 SW076411 24 56 0.002 0.013 1.9219 2.7235 0.86 10.32 0.43 4.8370 7.3134 1.68 20.16 0.84 SW076311-SW076310 SW076311 SW076310 21 253 0.001853 0.013 1.0790 1.7895 0.77 9.24 0.44 3.4651 4.9200 1.75 21.00 1.00 SW076306-SW076305 SW076306 SW076305 24 113 0.001973 0.013 1.8092 2.4514 0.86 10.32 0.43 4.0980 6.9445 1.72 20.64 0.86 SW076308-SW076307 SW076308 SW076307 24 176 0.001973 0.013 1.8086 2.4514 0.86 10.32 0.43 4.0965 6.9472 1.76 21.12 0.88 SW076307-SW076306 SW076307 SW076306 24 202 0.001973 0.013 1.8092 2.4514 0.86 10.32 0.43 4.0980 6.9459 1.74 20.88 0.87 SW076305-SW076304 SW076305 SW076304 24 262 0.001973 0.013 1.8095 2.4514 0.86 10.32 0.43 4.0988 6.9437 1.68 20.16 0.84 SW076304-SW076303 SW076304 SW076303 24 110 0.001973 0.013 1.8632 2.5362 0.88 10.56 0.44 4.1525 7.0277 1.62 19.44 0.81 SW066428-SW066427 SW066428 SW066427 24 265 0.001853 0.013 1.5928 2.5974 0.90 10.80 0.45 4.3653 6.3389 1.94 23.28 0.97 SW066427-SW066423 SW066427 SW066423 24 332 0.001853 0.013 1.5941 2.5973 0.90 10.80 0.45 4.3675 6.3226 2.00 24.00 1.00 SW066423-SW066426 SW066423 SW066426 24 314 0.001853 0.013 1.5941 2.5972 0.90 10.80 0.45 4.3675 6.2941 2.00 24.00 1.00 SW066426-SW066332 SW066426 SW066332 24 340 0.001853 0.013 1.5941 2.5970 1.02 12.24 0.51 4.3675 6.2731 2.00 24.00 1.00 SW076429-SW076428 SW076429 SW076428 21 265 0.001853 0.013 0.8560 1.4422 0.68 8.19 0.39 2.9737 4.2479 1.75 21.00 1.00 SW076408-SW076407 SW076408 SW076407 24 60 0.001973 0.013 1.4845 1.9397 0.76 9. 12 0.38 3.7267 6.3803 1.66 19.92 0.83 SW076407-SW076405 SW076407 SW076405 24 318 0.001973 0.013 1.4916 1.9508 0.78 9.36 0.39 3.7340 6.3857 1.70 20.40 0.85 SW076405-SW076433 SW076405 SW076433 24 56 0.001973 0.013 1.4930 1.9640 0.80 9.60 0.40 3.7354 6.3823 1.74 20.88 0.87 SW076409-SW076408 SW076409 SW076408 24 159 0.001973 0.013 1.4845 1.9397 0.74 8.88 0.37 3.7267 6.3846 1.64 19.68 0.82 SW076428-SW076427 SW076428 SW076427 21 39 0.001853 0.013 0.8570 1.4422 0.68 8.19 0.39 2.9753 4.2297 1.75 21.00 1.00 SW076309-SW066430 SW076309 SW066430 21 261 0.001853 0.013 1.0810 1.7892 0.84 10.08 0.48 3.4673 4.9200 1.75 21.00 1.00 SW066430-SW066424 SW066430 SW066424 24 44 0.001853 0.013 1.5928 2.5974 0.90 10.80 0.45 3.9857 5.7320 1.88 22.56 0.94 SW066424-SW066428 SW066424 SW066428 24 19 0.001852 0.013 1.5928 2.5974 0.90 10.80 0.45 4.1346 5.8699 1.90 22.80 0.95 OT066331-OT066329 OT066331 OT066329 27 661 0.001853 0.013 3.0950 4.6680 1.22 14.58 0.54 6.5817 9.5253 2.07 24.84 0.92 OT066329-OT057445 OT066329 OT057445 27 658 0.001853 0.013 3.0950 4.6671 1.08 12.96 0.48 6.5818 9.5251 1.69 20.25 0.75 SW076431-SW076424 SW076431 SW076424 9 24 0 0.013 0.1032 0.1852 0.30 3.60 0.45 0.6443 1.2292 0.64 7.68 0.96 SW076424-SW076430 SW076424 SW076430 9 23 0.070127 0.013 0.5851 0.9947 0.49 5.92 0.74 1.6066 1.8985 0.67 8.00 1.00 SSGM-17858 SW076302 SW067239 15 44 0.000334 0.013 1.0591 1.3714 0.86 10.35 0.69 1.9348 2.9417 1.25 15.00 1.00 SSGM-17857 SW067239 SW067238 15 39 0.000514 0.013 1.0591 1.3715 0.79 9.45 0.63 1.9348 2.9417 1.18 14.10 0.94 2334 2056 SW076424 24 52 0.001973 0.013 2.0863 2.9832 0.80 9.60 0.40 5.8913 8.8936 1.60 19.20 0.80 SW087319-SW087307 SW087319 SW087307 15 19 0.015207 0.013 0.8123 1.2180 0.41 4.95 0.33 1.6226 2.1647 1.05 12.60 0.84 24,622
Roughness
Existing Conditions Future Conditions
Katella Future
Future Capacity Deficiency Total
Pipe ID U/S MH ID D/S MH ID
Pipe
Diameter
(in)
Pipe
Length
(ft) Slope
Capacity
Deficiency
Location
g
Future
Capacity
Deficiency
Euclid St
Harbor Blvd
Anaheim Blvd State College Blvd
Orangewood Ave
Ball Rd
Harbor Blvd
Raymond Ave
State College BlvdOrangethorpe Ave
Kraemer Blvd
Placentia Ave
Chapman Ave
Lemon St
Euclid St
Lewis St
9th St
West St
Orangewood Ave
Ball Rd
La Palma Ave La Palma Ave
Cerritos Ave
Cerritos Ave
Broadway
Santa Ana River
91-FWY
91-FWY
57-FWY
5 Fwy
5 Fwy
3 2
1 4
6 8
7 5
Katella
Deficiencies
11 1
11 9
10 12
13 7
14 0 6,0003,000
US Feet
Legend
Existing Deficiency Location
Resort Area Deficiency
Future Deficiency Location
High d/D caused by backflow (not deficient)
City of Anaheim Sewer
City of Anaheim Sewer < 8" Diameter
Private Sewer
OCSD Trunk Sewer
General Plan Update Development Areas
Central Anaheim Service Area
³
1"=3,000'
Figure 7-2

CENTRAL ANAHEIM

SEWER MASTER PLAN
Capacity Deficiency LocationsPROJECT NO: 751879
DATE: April 2026

CAPACITY ANALYSIS

CITY OF ANAHEIM 7-7 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
7-3.3 Backflow Condition
The pipes identified as “High d/D caused by backflow (not deficient)” on Figure 7 -2, are cases, where the model showed d/D values above the City’s criteria but do not represent true capacity deficiencie s. This situation can occur when a smaller pipe connects to a larger one and the inverts match. Normally, sewers are designed so that the top of the pipes (soffits) are aligned to prevent backflow . In some cases, the inverts are aligned instead, as shown in Figure 7- 3. In this case , flow from the downstream pipe can back up into the smaller upstream pipe. Each of these locations in the model w as reviewed in detail to ensure that the peak flows could still be conveyed through the system . No improvement projects were recommended as long as the downstream pipe capacity met the City’s d/D criteria. It is recommended that the City verify the pipe inverts and connections (i.e. matching inverts or soffits) at these locations by review of record drawings and/or field survey.

Figure 7-3
Example Backflow Profile

7-4 Gravity Sewer Wet Weather Flow Analysis1
The Wet Weather Existing Condition model scenario is the basis of the wet weather flow analysis. This scenario was developed by building on top of the Dry Weather Existing Condition scenario, which accounts for sewer loads associated with peak attendance at the major attractions in the service area, as well as near future development and redevelopment projects. The estimated average RDII per manhole and the RDII diurnal patterns, discussed in Section 6- 7.1, were applied to the Dry Weather Existing Condition scenario.

The RDII estimates and patterns were based on the February 6, 2024 storm which was a 5 to 10 year storm event. The Wet Weather Existing Condition scenario therefore provides a realistic evaluation of the system performance based on actual field collected flow monitoring data. It is recommended that the City update the wet weather analysis when flow monitoring data from higher frequency storms becomes available.

CAPACITY ANALYSIS

CITY OF ANAHEIM 7-8 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
System capacity was considered deficient during a wet weather event when the pipe d/D exceeded 0.82, which is full capacity of the pipe. No sewer pipes were identified as flowing full during the wet weather analysis.

It is not practical to provide capacity in a sewer system for all foreseeable wet weather events as oversizing of pipes can create operation and maintenance issues such as debris deposition from low velocities and potential septic conditions. If wet weather hydraulic analyses are conducted and i f deficiencies are identified due to wet weather conditions, it is recommended that the City prioritize inflow reduction projects , since it has been identified to be more significant than infiltration as discussed in Section 4-7. 7-5 Small Diameter Gravity Sewers
The City continues to take a proactive approach to improving its sewer system. In addition to addressing capacity deficiencies, the City plans to upgrade all remaining 6- inch sewer pipes to a minimum of 8-inches in diameter, which is the minimum pipe size per the 2023 Sewer Design Manual.

The total length of the remaining 6- inch pipe in the system is 143,527 feet. The locations are shown on Figure 3- 2. Upgrading the 6- inch pipes will enhance system reliability, reduce the risk of blockages, and provide additional capacity for future development and redevelopment projects. Low flows per field observation and/or the hydraulic model should be considered during the design phase of the replacement sewers. Larger pipe sizes will create lower velocities. The City should be aware of possible sediment deposition issues, particularly near the upstream end of the system.

CITY OF ANAHEIM 8-1 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
SECTION 8

CAPITAL IMPROVEMENT PROGRAM
8-1 General
The primary goal of the development of the capital improvement projects is to provide the City with a long-range planning tool for implementing its sewer improvements in an orderly manner and a basis for financing these improvements. The recommended improvement project s were based upon the capacity analyses, and the costs were developed based upon sewer improvement project bid data for recent City projects.

The City’s Central Anaheim sewer system hydraulic model has been developed and refined over the past 20 years through three master plan projects . Improvements have been made to t he model geometry, including but are not limited to as-built plan review, field observations, field surveys, and flow monitoring.

The model results provide a high level analysis of the system capacity. The pipe capacity and condition should be confirmed through flow monitoring and closed -circuit television (CCTV) inspection prior to design and implementation of improvement projects. Pipe sizes should be reevaluated using survey information. Existing flows can be estimated from the City’s hydraulic model and flow monitoring data, while future flows for new or redeveloped areas should be calculated using the Sewer Load Factors in Table 5-2. The future pipe sizes and slopes should be designed to meet the established criteria with future estimated sewage flows.

The gravity main improvement projects recommended in this Sewer Master Plan are capacity related only.

Condition assessment of the gravity mains are evaluated separately by the City. 8-2 Project Priorities
The sewer improvement projects were selected primarily based upon health and safety concerns and minimizing the possibility of overflows. The projects that will eliminate the capacity deficiencies in the gravity collection system are prioritized as follows:

1. One pipe was identified with capacity deficiencies under existing peak dry weather flow conditions and is identified as the highest priority. Flow monitoring is recommended prior to project implementation.

2. The Katella Avenue and Cerritos Avenue Sewer Projects, located in the Resort Area, are currently in the design stage. These high-priority improvements have expedited construction schedules to ensure completion before the 2028 Summer Olympics, which is expected to significantly increase seasonal and event-driven visitor numbers and, consequently, sewage generation in the City.

3. Pipes identified as having capacity deficiencies under future sewer load conditions , but not under existing load conditions are considered lower in priority. Project priority will generally be determined by the schedule of development or redevelopment projects. As more detailed planning data becomes available, hydraulic analyses should be conducted to assess the available capacity in the existing sewers. If deficiencies are identified due to increased future flows, the City must implement the required gravity sewer improvements before the development or redevelopment can proceed.

4. The replacement of existing 6- inch pipes with a minimum 8- inch diameter are the lowest priority projects. These projects do not address capacity deficiencies but will enhance system reliability, reduce blockages, and support future development and redevelopment.

CAPITAL IMPROVEMENT PROGRAM

CITY OF ANAHEIM 8-2 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
8-3 Project Costs Sewer Loads
The pipe improvement recommendations are based on the
assumption that the existing pipes will be replaced in the same alignment. Where parallel OCSD facilities exist,
projects could instead include new connections directly to OCSD. However, replacement costs are generally more
conservative and will therefore allow the City more
flexibility for each project.

The total project costs include construction costs,
engineering design, administration, construction
management, inspection and contingencies. The
individual cost components are calculated as follows:

1. Unit pipe construction costs, shown in Table 8 -1,
were developed from bid information for recent
sewer pipeline projects (2023- 2025). These bids
are representative of current construction market
conditions within the study area. The resulting
replacement costs are higher than the estimates
would have been using the 2017 Central Anaheim
Master Plan of Sanitary Sewers costs increased
by the historical Engineering News Record (ENR)
Index for the Los Angeles area (ENRLA).

2. Pipe Construction Cost = Pipe Length x Unit Pipe Construction Cost

3. Engineering design, administration, construction management, inspection and contingency cost = 50% of the pipe construction cost
Construction costs are expected to fluctuate as changes occur in the economy. These costs should therefore be reevaluated and updated annually based upon ENRLA, with the base Index of 15,994.21 for October 2025. 8-4 Improvement Projects
The recommended gravity main capacity improvement projects are detailed in Table 8-2, and the locations are shown on Figure 8-1. A summary of the total costs for the City is as follows:

Existing Capacity Deficiency Improvements $0.94M
Future Capacity Deficiency Improvements $32.40M
Resort Area Improvement Projects $31.09M
Small Diameter Replacement Projects $223.90M
Total $288.33M
8-4.1 Capacity Deficient Projects
Sometimes the recommended improvement projects include pipe segments that extend beyond the calculated capacity deficiencies. In these cases, nearby pipes may not show a deficiency, but increasing their size to match the upstream pipe helps prevent potential bottlenecks in the system.

Pipe Size
(inches)
Pipe Construction Cost
($/ft)
8 $1,040
10 $1,300
12 $1,560
15 $1,950
18 $2,340
21 $2,520
24 $2,880
27 $3,240
30 $3,600
36 $4,320
42 $5,040
48 $5,760
Table 8-1
Unit Pipe Construction Costs
1 Unit Costs for construction are based on
$130/diameter-inch-foot for pipes 18" and smaller
and $120/diameter-inch-foot for pipes 21" and larger

CAPITAL IMPROVEMENT PROGRAM

CITY OF ANAHEIM 8-3 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
8-4.2 Resort Area Projects
Concurrent to this master planning effort, the resort area sewer improvements were analyzed and summarized in the Anaheim Resort Area Sanitary Sewer Study Final Preliminary Design Report (Resort Area Sewer PDR), which was completed by Woodard and Curran in May 2025. The recommended project locations for the Katella Avenue Sewer and the Cerritos Avenue Sewer projects are shown on Figure 8-1.

Katella Avenue Sewers
The recommended improvements presented in the Anaheim Resort Area Sewer PDR include replacement of pipes to increase capacity in the north Katella Avenue sewer and the construction of a third sewer in Katella Avenue to divert flows to the sewers in West Street and Wakefield Avenue. The Katella Avenue sewer improvements are currently in the design stage and will address the sewer capacity deficiencies.

Cerritos Avenue Sewer
The Resort Area Sewer PDR recommended the Cerritos Avenue sewer improvements to reduce the sewer flows in the north Katella Avenue sewer. As part of the project recommendation, all flows at split Manhole 22 (Cerritos Avenue and Walnut Street) were diverted to the existing sewer in Cerritos Avenue. This resulted in deficiencies in Cerritos Avenue between Walnut Street and the OCFCD Anaheim Barber City Channel, as well as backflow conditions in Walnut Street, north of Cerritos. The Cerritos Avenue sewer improvements are currently in the design stage and will address both the capacity deficiencies and backflow conditions.

Project Costs
The City has reached an agreement with developers to contribute approximately $10 million toward the total resort area project costs. The City’s share of $31.09M reflects the combined cost of the Katella Avenue Sewer Project ($35.76M) and the Cerritos Avenue Sewer Project ($5.33M), minus the $10M developer contribution, as detailed in Table 8-2.
8-4.3 Future Deficiency Location P-11
There are existing parallel sewers in Harbor Boulevard between Katella Avenue and Manchester Avenue. There is an 18 -inch sewer on the west side of the street and a 15- inch sewer on the east side of the street. Flow monitoring data from the Resort Area Sewer PDR indicate that the majority of the existing flows are conveyed by the easterly 15-inch sewer, and the hydraulic model assumes the existing and future Disneyland flows also connect to this sewer.

Based on the updated hydraulic model, the easterly sewers are undersized, as shown on Figure 7- 2.

Reallocation of existing and projected Disneyland flows to the westerly 18- inch sewer results in both sewers meeting the City’s capacity criteria for 12- inch and larger pipes (d/D = 0.75) under future loading conditions.

However, the resulting d/D ratios approach the criteria threshold, indicating limited remaining capacity. Future loading is projected from Disneyland and General Plan Redevelopment Areas, and the existing capacity is sensitive to changes in development assumptions.

At this time, no pipe improvements are recommended. It is recommended that the City continue to monitor future development to ensure the sewer capacity remains adequate and identify when sewer improvements may become necessary. In addition, the City should require that the Disneyland laterals connect to the 18-inch sewer on the west side of Harbor Boulevard during design review and approval.

CAPITAL IMPROVEMENT PROGRAM

CITY OF ANAHEIM 8-4 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
8-4.4 Small Diameter Replacement Projects
The City plans to upgrade all remaining 6- inch sewer pipes to a minimum of 8- inches in diameter to enhance system reliability, reduce the risk of blockages, and provide additional capacity for future development and redevelopment projects. The 6-inch diameter pipe replacement projects include a total of 143,527 feet at a cost of $223.90M. A detailed summary of these pipes and associated costs is provided in Appendix 8-1.

CAPITAL IMPROVEMENT PROGRAM

CITY OF ANAHEIM 8-5 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table 8-2
Capacity Improvement Projects

Capital
Improvement
Project ID Location Pipe ID U/S MH ID D/S MH ID
Existing
Pipe
Diameter
(in)
Existing
Length (ft)
Existing
Slope
Peak Dry
Weather
Flow d/D
Peak Dry
Weather
Flow
(MGD)
Proposed
Pipe
Diameter
(in)
Unit
Cost
($/ft)1
Construction
Cost ($)2
Total Cost
($)
Project Total
Cost ($) Description
SW067222-SW067406 SW067222 SW067406_A 10 319 0.0045 0.68 0.8135 12 $1,560 $496,907 $745,360 SW077111-SW067222 SW077111 SW067222 8 85 0.0057 0.96 0.8189 12 $1,560 $132,070 $198,104 403 $628,976 $943,465 $943,465
SW096304-SW096303 SW096304 SW096303 8 352 0.0030 0.73 0.3677 12 $1,560 $549,635 $824,452 SW096302-SW096305 SW096302 SW096305 10 368 0.0024 0.93 0.7050 12 $1,560 $574,454 $861,682 SW096303-SW096302 SW096303 SW096302 8 349 0.0028 0.85 0.4504 12 $1,560 $544,393 $816,590 SW096311-SW096310 SW096311 SW096310 8 358 0.0024 1.00 0.3940 12 $1,560 $559,182 $838,773 SW096307-SW096305 SW096307 SW096305 8 361 0.0024 0.86 0.6500 12 $1,560 $563,753 $845,629 SW096309-SW096308 SW096309 SW096308 8 176 0.0029 1.00 0.6449 12 $1,560 $275,106 $412,659 SW096310-SW096309 SW096310 SW096309 8 177 0.0029 1.00 0.6287 12 $1,560 $275,683 $413,525 SW096308-SW096307 SW096308 SW096307 8 344 0.0024 1.00 0.6459 12 $1,560 $536,266 $804,398 SW117304-SW117303 SW117304 SW117303 10 261 0.0038 0.84 1.3872 15 $1,950 $508,677 $763,016 SW117411-SW117409 SW117411 SW117409 10 93 0.0043 1.00 0.5329 15 $1,950 $182,306 $273,458 SW117409-SW117408 SW117409 SW117408 10 211 0.0029 1.00 1.1551 15 $1,950 $412,074 $618,111 SW117408-SW117405 SW117408 SW117405 10 139 0.0019 1.00 1.1638 15 $1,950 $271,323 $406,985 SW117405-SW117404 SW117405 SW117404 10 135 0.0053 1.00 1.3153 15 $1,950 $263,270 $394,904 SW117404-SW117304 SW117404 SW117304 10 304 0.0027 1.00 1.3168 15 $1,950 $592,176 $888,264 SW117302-OT117112 SW117302 OT117112 10 21 0.0472 0.47 1.3871 15 $1,950 $40,463 $60,694 Recommended to prevent bottle neck SW117303-SW117302 SW117303 SW117302 10 120 0.0056 0.74 1.3875 15 $1,950 $234,293 $351,439 SW117412-SW117411 SW117412 SW117411 10 107 0.0037 0.80 0.4708 15 $1,950 $207,831 $311,747 SW117416-SW117409 SW117416 SW117409 8 158 0.0016 1.00 0.7818 12 $1,560 $247,057 $370,586 SW096305-SW086411 SW096305 SW086411 12 135 0.0057 1.00 1.0749 15 $1,950 $262,646 $393,968 SW086411-SW086409 SW086411 SW086409 12 284 0.0024 1.00 1.1107 15 $1,950 $554,522 $831,782 SW086409-SW086408 SW086409 SW086408 12 292 0.0023 0.91 1.1107 15 $1,950 $570,278 $855,416 SW086408-SW086407 SW086408 SW086407 12 93 0.0028 0.72 1.1107 15 $1,950 $181,428 $272,142 Recommended to prevent bottle neck SW087302-SW087301 SW087302 SW087301 10 234 0.0031 0.69 0.6961 12 $1,560 $365,087 $547,630 SW087301-SW087106 SW087301 SW087106 10 219 0.0048 0.81 0.6961 12 $1,560 $341,016 $511,524 SW107109-SW107108 SW107109 SW107108 8 361 0.0035 0.81 0.4998 12 $1,560 $563,909 $845,863 SW107110-SW107109 SW107110 SW107109 8 339 0.0014 1.00 0.3689 10 $1,300 $440,804 $661,206 SW107111-SW107110 SW107111 SW107110 8 362 0.0023 0.76 0.2004 10 $1,300 $470,574 $705,861 $2,212,930E Howell Ave and S Lewis StProject 07
Project 046 E Howell Ave between S Sinclair St and west of S Sunkist St
E Cerritos Ave and S Anaheim BlvdProject 036
Project 05
Existing Improvement ProjectSouth of W Eleanor Dr and S West StProject 01 Project 026 E Palais Rd and S Anaheim Blvd
Existing Capacity Deficiency Improvement Project Total
$943,465
$2,502,724
W Midway Dr and Anaheim Blvd
Project 06 W Disney Way and S Harbor Blvd
$3,314,984
$4,439,202
$2,353,309
$1,059,154

CAPITAL IMPROVEMENT PROGRAM

CITY OF ANAHEIM 8-6 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table 8-2 (Continued)
Capacity Improvement Projects

Capital
Improvement
Project ID Location Pipe ID U/S MH ID D/S MH ID
Existing
Pipe
Diameter
(in)
Existing
Length (ft)
Existing
Slope
Peak Dry
Weather
Flow d/D
Peak Dry
Weather
Flow
(MGD)
Proposed
Pipe
Diameter
(in)
Unit
Cost
($/ft)1
Construction
Cost ($)2
Total Cost
($)
Project Total
Cost ($) Description
SW108208-SW108203 SW108208 SW108203 8 319 0.0024 1.00 0.4739 10 $1,300 $414,635 $621,953 SW108203-SW108201 SW108203 SW108201 8 318 0.0021 0.93 0.4625 10 $1,300 $413,465 $620,198 SW108201-SW107409 SW108201 SW107409 8 322 0.0038 0.73 0.4643 10 $1,300 $419,003 $628,505 SW119107-SW119106 SW119107 SW119106 8 275 0.0020 0.76 0.3624 10 $1,300 $357,916 $536,874 SW119108-SW119107 SW119108 SW119107 8 271 0.0020 0.73 0.3072 10 $1,300 $352,326 $528,489 SW119106-SW118309 SW119106 SW118309 8 277 0.0079 0.78 0.4470 12 $1,560 $432,806 $649,210 SW119214-SW119210 SW119214 SW119210 8 251 0.0029 0.71 0.3687 10 $1,300 $326,300 $489,450 SW119206-OC_SW119206 SW119206 OC_SW119206 8 337 0.0042 0.64 0.4026 10 $1,300 $438,243 $657,365 SW119210-SW119206 SW119210 SW119206 8 215 0.0051 0.69 0.3965 10 $1,300 $279,734 $419,601 SW102326-SW103103 SW102326 SW103132 8 358 0.0047 0.69 0.4038 10 $1,300 $465,764 $698,646 SW102415-SW102326 SW102415 SW102326 8 307 0.0038 0.64 0.3548 10 $1,300 $399,048 $598,572 SW103102-SW103101 SW103102 SW103101 8 105 0.0040 0.68 0.4526 10 $1,300 $136,500 $204,750 SW103103-SW103102 SW103103 SW103131 8 61 0.0036 0.74 0.4142 10 $1,300 $79,638 $119,457 2362 SW103132 SW103103 8 57 0.0036 0.73 0.4103 10 $1,300 $74,451 $111,677 2364 SW103131 SW103102 8 277 0.0034 0.76 0.4191 10 $1,300 $360,568 $540,852 SW069403-SW069402 SW069403 SW069402 8 314 0.0022 0.58 0.0872 12 $1,560 $490,152 $735,228 SW069402-SW069401 SW069402 SW069401 8 313 0.0021 0.68 0.3282 12 $1,560 $488,717 $733,075 SW087313-SW087311 SW087313 SW087311 21 126 0.0020 0.90 5.0336 27 $3,240 $406,976 $610,465 SW087315-SW087318 SW087315 SW087318 21 94 0.0020 0.91 4.9703 27 $3,240 $303,523 $455,285 SW087415-SW087414 SW087415 SW087414 21 147 0.0020 0.89 4.0365 27 $3,240 $474,757 $712,136 SW087414-SW087413 SW087414 SW087413 21 104 0.0020 0.92 4.8209 27 $3,240 $335,599 $503,399 SW087318-SW087313 SW087318 SW087313 21 116 0.0020 0.91 4.9742 27 $3,240 $375,678 $563,517 SW087311-SW087309 SW087311 SW087309 21 213 0.0020 0.88 5.0577 27 $3,240 $690,638 $1,035,958 SW087413-SW087425 SW087413 SW087425 21 90 0.0020 0.92 4.9617 27 $3,240 $292,248 $438,372 SW087317-SW087315 SW087317 SW087315 21 124 0.0020 0.91 4.9660 27 $3,240 $402,311 $603,466 SW087425-SW087317 SW087425 SW087317 21 239 0.0020 0.92 4.9675 27 $3,240 $775,948 $1,163,921 SW087309-SW087307 SW087309 SW087307 21 317 0.0020 0.73 5.0577 27 $3,240 $1,027,210 $1,540,814 Recommended to prevent bottle neck 12,305 $21,602,357 $32,403,535 $32,403,535Future Capacity Deficiency Improvement Project Total South of E Katella Ave and S State Colleger
B lvdProject 08 $1,870,655
Project 14 West of W Katella Ave and S Clementine St
$1,714,573
$7,627,333
$1,468,303
$2,273,954
$1,566,416Project 10 North of S Towne Centre Pl and Rampart St Project 12 Southwest of E Lincoln Ave and N Evelyn Dr
East of Durst St and N Lemon StProject 13
Project 09 South of E Orangewood Ave and S Dupont Dr

CAPITAL IMPROVEMENT PROGRAM

CITY OF ANAHEIM 8-7 Central Anaheim Sewer Master Plan
R:Rpts\\Anaheim\2025_Central Anaheim Sewer Master Plan
Table 8-2 (Continued)
Capacity Improvement Projects

CENTRAL ANAHEIM

Anaheim City CouncilAugust 25, 2026

Anaheim City Council
August 25, 2026