2019 Excellence in Environmental Engineering and Science® Awards Competition Winner

Honor Award - Planning

Wastewater Collection and Treatment Facilities Master Plan

Entrant: Orange County Sanitation District
Engineer in Charge: Eros Yong, P.E., BCEE
Location: Fountain Valley, California
Media Contact: Eros Yong and Daisy Covarrubias

Entrant Profile

Orange County Sanitation District (OCSD) is a publicly-owned water resource recovery facility that provides wastewater collection, treatment, and disposal services for approximately 2.6 million people in central and northwest Orange County, California. OCSD has two treatment plants that treat residential, commercial, and industrial wastewater; Plant No. 1 in Fountain Valley and Plant No. 2 in Huntington Beach. Together both plants currently treat nearly 185 million gallons per day (mgd).

Over the years, OCSD has evolved from a wastewater treatment facility to a resource recovery facility that treats wastewater as the resource that it is, not a waste. Every day at OCSD, wastewater is being converted into clean water, energy, and soil amendments.

To assure OCSD's capability to meet regulatory requirement, future capacity demands, level of service goals, and to meet our Board of Director's policies for enhanced resource recovery and energy independence, OCSD completed a Wastewater Collection and Treatment Facilities Master Plan in 2017 to lay out a 20-year Capital Improvement Program (CIP) that coordinates and optimizes the refurbishment and replacement of our collection system and treatment facilities.

The 2017 Wastewater Collection and Treatment Facilities Master Plan was performed by OCSD staff and a consultant team comprised of Carollo Engineers and Brown and Caldwell.

Project Description

Overview

OCSD recently completed capital expenditures of over $500 million for transition of their two treatment plants to full secondary, as well as improvements to provide over 100 MGD of secondary effluent to Orange County Water District's (OCWD) Groundwater Replenishment System (GWRS) for potable reuse.

OCSD is now facing a time when dry-weather influent flows have decreased, ocean outfall discharge flows have decreased (due to recycling), and discharge regulations have stabilized. When the Wastewater Collection and Treatment Facilities Master Plan (Facilities Master Plan) project was started, OCSD staff acknowledged that capacity and emerging regulations were important and required evaluation; however, the challenge was addressing rehabilitation and replacement of their aging infrastructure. With lower flows and aging infrastructure, much of the capital improvements and ongoing operational costs will be focused on infrastructure maintenance, asset management, and resiliency.

Integrated Approach

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The Facilities Master Plan effort included integration of ongoing initiatives and recent master planning efforts to create a CIP that is focused on strategic goals set by OCSD's Board of Directors. The initiatives/efforts incorporated include:

Indirect Potable Reuse. Through the GWRS, treated wastewater from OCSD Plant No. 1 is recycled reducing the reliance of surrounding communities on costly imported water, and provides a sustainable solution to an extended period of drought. The Facilities Master Plan incorporates projects that will increase the supply of treated wastewater to the GWRS by conveying OCSD Plant No. 2 treated wastewater to OCWD.
Biosolids. The Biosolids initiative focuses on diversifying OCSD's biosolids management options to create a sustainable and cost-effective biosolids program. Through integration of a recently completed Biosolids Master Plan into the Facilities Master Plan, OCSD will begin implementing projects to convert their existing digestion facilities to produce Class A Exceptional Quality biosolids, which will provide more opportunities for beneficial use for local agriculture and soil blending.
Food Waste/Biogas. By receiving and treating pre-processed source separated organics, OCSD is helping to reduce the volume of waste being sent to landfills. Two food waste facilities have been identified by the Biosolids Master Plan and incorporated into the Facilities Master Plan: 1) an interim facility which will immediately provide some relief to local landfills and build partnerships with surrounding waste haulers; 2) the ultimate facility which will provide enough receiving capabilities to support the local area. An added side-effect of accepting food waste is an anticipated increase in biogas production. OCSD is currently using biogas as an alternative fuel source to cogeneration engines. Using biogas not only provides a cheaper alternative to imported natural gas or imported electricity but also reduces the wastewater treatment plant's carbon dioxide emissions.
Odor Control. The majority of OCSD facilities are located in dense communities adjacent to homes, schools, businesses, and other public areas. The Facilities Master Plan augmented existing CIP projects with findings from the recently completed Odor Control Master Plan to mitigate odors extending beyond OCSD boundaries.

Quality

With the completion of the Facilities Master Plan, OCSD moved from a 20-year CIP consisting of projected cashflow based on percentages of total asset values to a CIP that is based on compilation of well-defined projects with thorough project descriptions, cost estimates and schedule. The proposed 20-year CIP resulted in a rate increase of 1.2 percent annually for the next five years, which is less than the anticipated rate of inflation. The OCSD Board of Directors unanimously adopted the Facilities Master Plant in December 2017, solidifying OCSD's commitment to the proposed CIP that will provide a sustainable and reliable wastewater collection, and treatment and resource recovery facility for central and northern Orange County.

Innovation

The condition assessment of OCSD's collection system pipelines were evaluated using Closed Circuit Television (CCTV) inspections focusing on the structural defects that could be indicative of renewal or repair needs. The data was extracted from approximately 1,100 databases, including over 53,000 defects for approximately 7,000 surveys spanning over 20 years. Rigorous refinement of the data to eliminate duplicate data was conducted before the data was imported into a GIS- based asset integrity management and capital planning software called InfoMaster for further analysis. InfoMaster was used to generate defect scores for each pipe segment. The software allows quick reviews of the CCTV inspections by skipping from one defect to the next with a press of a button. The use of InfoMaster allows users to accurately estimates the likelihood of failure.

Complexity

The Facilities Master Plan provided a framework for a very complex 20-year CIP; with over 80 well defined capital projects, each complete with project justification, project description, cost estimate, and an implementation schedule.

Highlights of the proposed CIP plan includes:

Rehabilitation and replacement of most of the treatment processes at both treatment plants, and off-site pump stations
Conversion of Plant No. 2 digestion process to produce a Class A biosolids product
Modification of existing facilities and addition of new facilities to enable the recycling of Plant No. 2 treated effluent
Rehabilitation of the five-mile ocean outfall to extend its useful life
Capital spending of $5 billion over a 20-year period resulting in $250 million per year

The Facilities Master Plan established a clear and concise road map which is essential for maintaining reliable and resilient facilities to protect public health.

Contribution to Social and Economic Advancement

The following OCSD's Mission Statements were the guiding principles during the preparation of the Facilities Master Plan:

Providing reliable, responsive, and affordable services in line with customer needs and expectations.
Protecting public health and the environment utilizing all practical and effective means for wastewater, energy, and solids resource recovery.
Continually seeking efficiencies to ensure that the public's money is wisely spent.

The Facilities Master Plan resulted in the following social and economic benefits:

Capital spending of $250 million per year will create local jobs in Orange County.
A well-planned 20-year CIP allows for proactive spending as opposed to costly reactive spending (emergency repairs, etc.).
The Facilities Master Plan supports GWRS' goal to reduce reliance on imported water through providing high quality and reliable source water.

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<
p>OCSD's sewer service has two main components: the collection system and the treatment and recycling facilities. The collection system contains 15 pump stations and 396 miles of regional trunk sewer that collect wastewater from OCSD's 479-square-mile service area. This wastewater is conveyed to Reclamation Plant No. 1 in Fountain Valley and Treatment Plant No. 2 in Huntington Beach, where treatment and resource recovery take place. While some of this treated water is released five miles off shore through a deep-water ocean outfall system, most is recovered into Orange County's main water supply. This is accomplished by way of a joint project with the Orange County Water District, the Groundwater Replenishment System – the world's largest advanced water purification system for indirect potable reuse.	Aerial Image of Orange County Sanitation District (OCSD) Reclamation Plant No. 1, circa 1957.

Aerial Image of Orange County Sanitation District (OCSD) Reclamation Plant No. 1, circa 2017.	Aerial Image of Orange County Sanitation District (OCSD) Treatment Plant No. 2, circa 1957.

Aerial Image of Orange County Sanitation District (OCSD) Treatment Plant No. 2, circa 2017.	The Facilities Master Plan Central Generation Condition Assessment Team consisted of multiple discipline experts, OCSD O&M staff, and OCSD asset engineers. Assessments were conducted at Plant Nos. 1 and 2 and off-site pump stations to determine asset condition and identify necessary improvement or replacement projects. In many cases, the assessment revealed that the structural facilities are in sound condition, but the mechanical systems must be either rehabilitated or replaced due to age, obsolescence, and deterioration.

The multi-discipline Facilities Master Plan Condition Assessment Team maintained an approach focusing on translating assessment findings into large CIP projects.	Plant No. 1 Central Generation was constructed in 1994. Engines are periodically rebuilt as part of routine maintenance cycles. However, major support systems will reach the end of their useful lives over the next 10-20 years and will need to be replaced or refurbished.

Plant No. 1 trickling filters and clarifiers were constructed in 2006. Although the facility is relatively new at the time of the Facilities Master Plan, a project to rehabilitate the facility is now part of the 20-year CIP. This project is projected to start in about 15 years.	A Street Pump Station in Newport Beach is one of OCSD's 15 pump stations. It was constructed to blend in with the neighborhood. Twelve pump station projects were identified as part of the Facilities Master Plan.

OCSD has about 396 miles of gravity pipelines and force mains. Approximately 40 miles of pipe rehabilitation during the FMP assessment. The result is 25 sewer pipeline projects amounting to $497 million.