MIDDLESEX WATER CO (MSEX) Business

Item 1.                Business.

The terms “the Company,” “we,” “our,” and “us” collectively refer to Middlesex Water Company (Middlesex) and its subsidiaries, including Tidewater Utilities, Inc. (Tidewater) and Tidewater’s wholly-owned subsidiaries, Southern Shores Water Company, LLC (Southern Shores) and White Marsh Environmental Systems, Inc. (White Marsh). The Company’s other subsidiaries are Pinelands Water Company (Pinelands Water) and Pinelands Wastewater Company (Pinelands Wastewater) (collectively, Pinelands), Utility Service Affiliates, Inc. (USA) and Utility Service Affiliates (Perth Amboy) Inc. (USA-PA).

Overview

Middlesex was incorporated as a water utility company in 1897 and owns and operates regulated water utility and wastewater systems primarily in New Jersey and Delaware. Middlesex also operates water and wastewater systems under contract on behalf of municipal and private clients primarily in New Jersey and Delaware. Across our regulated utility systems, we serve approximately 131,000 customers. We operate water and wastewater systems under unregulated contracts for governmental entities and private entities.

Our principal executive offices are located at 485C Route 1 South, Suite 400, Iselin, New Jersey 08830. Our telephone number is (732) 634-1500. Our website address is www.middlesexwater.com. Information contained on our website is not part of this Annual Report on Form 10-K. We make available, free of charge through our website, reports and amendments filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, after such material is electronically filed with or furnished to the United States Securities and Exchange Commission (the SEC). We also periodically provide certain information for investors on our website, and our investor relations website, investors.middlesexwater.com. This includes press releases and other information about dividends on the Company’s equity securities.

Middlesex System

Located in New Jersey, the Middlesex System provides water services to approximately 61,000 retail customers, primarily in eastern Middlesex County, and under wholesale contracts to the City of Rahway, Townships of Edison and Marlboro, the Borough of Highland Park and the Old Bridge Municipal Utilities Authority. The Middlesex System treats, stores and distributes water for residential, commercial, industrial and fire protection purposes. The Middlesex System also provides water treatment and pumping services to the Township of East Brunswick under contract. The amount of water supply allocated to the Township of East Brunswick is granted directly to the Township by the New Jersey Water Supply Authority. The Middlesex System produced approximately 67% of our 2025 consolidated operating revenues.

The Middlesex System’s retail customers are located in an area of approximately 55 square miles in Woodbridge Township, the City of South Amboy, the Boroughs of Metuchen and Carteret, portions of the Township of Edison and the Borough of South Plainfield, all in Middlesex County, and a portion of the Township of Clark in Union County. Retail customers include a mix of residential customers, large industrial concerns and commercial and light industrial facilities. These customers are located in generally well-developed areas of central New Jersey.

The contract customers of the Middlesex System comprise an area of approximately 110 square miles with a population of over 0.2 million. Contract sales to the Townships of Edison and Marlboro, the City of Rahway and the Old Bridge Municipal Utilities Authority are supplemental to the water systems owned and operated by these customers. Middlesex is the primary source of water for the Borough of Highland Park and the Township of East Brunswick.

Tidewater System

Tidewater, together with its wholly-owned subsidiary, Southern Shores, provides water services to approximately 65,000 retail customers for residential, commercial and fire protection purposes in over 485 separate communities in New Castle, Kent and Sussex Counties, Delaware. The Tidewater System produced approximately 25% of our 2025 consolidated operating revenues.

Pinelands Systems

Pinelands Water provides water services to approximately 2,500 residential customers in Burlington County, New Jersey. Pinelands Water is not physically interconnected with the Middlesex System. Pinelands Water produced approximately 1% of our 2025 consolidated operating revenues.

Pinelands Wastewater provides wastewater collection and treatment services to approximately 2,500 residential customers and one municipal wastewater system in Burlington County, New Jersey. Pinelands Wastewater produced approximately 1% of our 2025 consolidated operating revenues.

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USA-PA

USA-PA operates the City of Perth Amboy, New Jersey’s (Perth Amboy) water and wastewater systems under a ten-year agreement, which expires in December 2028. In addition to performing day-to day operations, USA-PA is also responsible for emergency responses and management of capital projects funded by Perth Amboy. USA-PA produced approximately 4% of our 2025 consolidated operating revenues.

USA

USA operates the Borough of Avalon, New Jersey’s (Avalon) water utility, sewer utility and storm water system under a ten-year operations and maintenance contract expiring in 2032. In addition to performing day-to-day service operations, USA is responsible for emergency responses and management of capital projects funded by Avalon.

USA operates the Borough of Highland Park, New Jersey’s (Highland Park) water utility and sewer utility under a ten-year operations and maintenance contract expiring in 2030.

Under a marketing agreement with HomeServe USA Corp. (HomeServe) expiring in 2031, USA offers residential customers in New Jersey and Delaware various water and wastewater related home maintenance programs. HomeServe is a leading national provider of such home maintenance service programs. USA receives a service fee for the billing, cash collection and other administrative matters associated with HomeServe’s service contracts.

USA produced approximately 2% of our 2025 consolidated operating revenues.

White Marsh

White Marsh operates or maintains water and/or wastewater systems that serve approximately 3,700 service connections under 28 separate contracts, primarily in New Castle, Kent and Sussex Counties, Delaware. White Marsh also owns two commercial properties that are leased to Tidewater for its administrative office campus and its field operations center. White Marsh produced approximately 0.5% of our 2025 consolidated operating revenues.

Financial Information

Consolidated operating revenues, operating income and net income are as follows:

Operating revenues were earned from the following sources:

Water Supplies and Contracts

Our New Jersey and Delaware water supply systems are physically separate and are not interconnected. In New Jersey, the Pinelands System is not interconnected with the Middlesex System. We believe we have adequate sources of water supply to meet the current service requirements of our present customers in New Jersey and Delaware.

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Middlesex System

Our Middlesex System produced approximately 13.8 billion gallons in 2025 from:

•The Carl J. Olsen Surface Water Treatment Plant (CJO Plant)-10.1 billion gallons;

•Company-owned wells (ground water)-2.7 billion gallons; and

•The balance purchased from a non-affiliated water utility regulated by the New Jersey Board of Public Utilities (NJBPU) under an agreement which expires February 27, 2031. This agreement provides for minimum purchases of 3.0 million gallons per day (mgd) of treated water with provisions for additional purchases.

The Middlesex System’s distribution storage facilities are used to supply water to customers at times of peak demand, outages and emergencies.

The principal source of surface water for the Middlesex System is the Delaware & Raritan Canal, which is owned by the State of New Jersey and operated by the New Jersey Water Supply Authority (NJWSA). Middlesex has an agreement with NJWSA for the purchase of untreated water through November 30, 2048. This agreement with the NJWSA provides for average purchases of 27 million gallons a day (mgd), with a peak up to 47.0 mgd. Pricing is set annually by the NJWSA through a public rate making process. The agreement has provisions for additional pricing in the event Middlesex overdrafts or exceeds certain monthly and annual thresholds. The untreated surface water is pumped to, and treated at, the CJO Plant.

Tidewater System

Our Tidewater System, together with our wholly-owned subsidiary, Southern Shores, produced approximately 3.2 billion gallons in 2025, primarily from 166 wells. Tidewater expects to submit applications to Delaware regulatory authorities for the approval of additional wells as growth, customer demand and water quality warrant. Tidewater augments its water production with annual purchases of approximately 75.0 million gallons of treated water from the City of Dover, Delaware. Tidewater does not have a central water treatment facility for the over 485 separate communities it serves. As the number has grown, many of Tidewater’s individual systems have been interconnected, forming several regional systems that are served by multiple water treatment facilities owned by Tidewater.

Pinelands Water System

Water supply to our Pinelands Water System is derived from four wells which produced approximately 123 million gallons in 2025. The aggregate pumping capacity of the four wells is 2.2 mgd.

Wastewater Facilities

Pinelands Wastewater System

The Pinelands Wastewater System discharges into the South Branch of the Rancocas Creek through a wastewater treatment plant that provides clarification, sedimentation, filtration and disinfection. The total capacity of the plant is 0.5 mgd, and the system treated approximately 87.0 million gallons in 2025.

Human Capital Management

The Company strives to attract and retain employees by offering competitive compensation and benefits along with career development and training opportunities in a safe, supportive and inclusive work environment. Our mission, our business philosophy and the manner in which we deliver value for our customers, our shareholders and our employees, is inherent in what we, as an enterprise, profess to be our core values of Respect, Invest, Growth, Honesty and Teamwork. Our employees’ success is a key element of the Company’s success.

Workforce

As of December 31, 2025, the Company had 395 employees. None of our employees are subject to a collective bargaining agreement. We believe our employee relations are positive.

Employee Compensation and Benefits

The Company provides competitive compensation and benefits programs designed to attract, retain, and motivate qualified employees. Compensation is structured based on job responsibilities, skill level, experience, and geographic market considerations. The Company periodically reviews and evaluates its compensation programs, including through independent benchmarking against industry peers and relevant labor markets.

Compensation increases and incentive compensation are merit-based and linked to individual performance, as documented through the Company’s bi-annual performance management process.

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The Company offers a range of benefits intended to support employees’ physical, mental, and financial well-being, including healthcare coverage, employer-funded retirement plans, insurance programs, and other benefits consistent with market practice.

Safety

The Company has implemented safety programs and management practices designed to promote a safe work environment and protect employee health. These programs include required safety training for all employees, as well as role-specific qualifications and certifications for certain operational positions.

Employees are encouraged to identify and report unsafe conditions and are authorized to stop work they reasonably believe presents a safety risk or does not comply with Company safety policies and procedures. The Company maintains a policy of non-retaliation for employees who raise safety concerns or exercise stop-work authority in good faith.

Employee Development and Training

The Company maintains training and educational programs designed to support workforce capability, operational effectiveness, and risk awareness. These programs include company-wide and role-specific training initiatives delivered through Middlesex Water Company Academy, the Company’s internal learning and development framework that supports onboarding, role-based training, leadership development, and ongoing professional development. The Company also offers tuition assistance for eligible full-time employees enrolled in pre-approved undergraduate, graduate, or professional licensing programs.

Employees receive training to identify and report operational, financial, cybersecurity, physical security and other enterprise risks, including risks related to the protection and use of sensitive data, physical risks and risks to the Company’s brand and reputation, reinforcing accountability and responsible risk management.

Executive management and the Board of Directors regularly review leadership development progress, workforce planning, and succession planning for key leadership positions. In addition, formal succession plans have also been established for certain critical roles to support business continuity and long-term organizational needs.

Workplace Culture

The Company seeks to maintain a professional work environment in which employees are treated with respect and provided opportunities to contribute and develop based on their skills, experience, and performance. The Company focuses on the recruitment and development of both external and internal candidates to support workforce continuity and organizational effectiveness.

Competition

Our business in our franchised service areas is substantially free from direct competition for growth with other public utilities, municipalities and other entities. However, our ability to provide contract wholesale water supply and operations and maintenance services that are not under the jurisdiction of a state public utility commission is subject to competition from other public utilities, municipalities and other entities. Although Tidewater has been granted exclusive franchises for its existing community water systems, the ability to expand service areas can be affected by the Delaware Public Service Commission (DEPSC) awarding franchises to other regulated water utilities with whom we compete for such franchises and for projects.

Regulation

Our rates charged to customers for utility services, the quality of the services we provide and certain other matters are regulated by the state public utility commissions in the states where we operate, including the NJBPU and the DEPSC (collectively, the Public Utility Commissions).

Our USA, USA-PA and White Marsh subsidiaries are not regulated public utilities as related to rates and service quality. However, they are subject to federal and state environmental regulations with respect to water quality and wastewater effluent quality to the extent such services are provided.

We are subject to environmental and water quality regulation by the following regulatory agencies (collectively, the Government Environmental Regulatory Agencies):

•United States Environmental Protection Agency (USEPA);

•New Jersey Department of Environmental Protection (NJDEP) with respect to operations in New Jersey; and

•Delaware Department of Natural Resources and Environmental Control, the Delaware Department of Health and Social Services-Division of Public Health (DEDPH), and the Delaware River Basin Commission with respect to operations in Delaware.

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In addition, our issuances of equity securities are subject to the prior approval of the NJBPU and require registration with the United States Securities and Exchange Commission. Our issuances of long-term debt securities are subject to the prior approval of the respective state Public Utility Commissions.

Regulation of Rates and Services

For regulated rate setting purposes, we account separately for our regulated utility operations to facilitate independent rate setting by the applicable Public Utility Commissions.

In determining our regulated utility rates, the respective Public Utility Commissions consider the revenue, expenses and utility infrastructure used and useful in providing service to the public. Rate determinations by the respective Public Utility Commissions do not guarantee achievement by our regulated utility companies of specific rates of return for our regulated utility operations. Thus, we may not achieve the rates of return authorized by the Public Utility Commissions. In addition, there can be no assurance that any future rate increases will be granted or, if granted, that they will be in the amounts requested.

Rate Matters

Middlesex - In February 2026, the NJBPU approved:

•$14.5 million of base rate increases for Middlesex and Pinelands, effective February 23, 2026;

•A Resiliency and Environmental System Improvement Charge (RESIC) Foundational Filing, which allows for the recovery of certain costs of future Middlesex and Pinelands investments related to compliance with requirements to address existing and emerging chemical elements or compounds, installation of new plant or equipment or replacement of existing plant or equipment to further maintain, enhance, or improve resiliency, health, safety or environmental protection; and

•A Distribution System Improvement System Charge (DSIC) Foundational Filing, which allows for the recovery of future Middlesex and Pinelands Water investments in qualifying capital improvements to their water distribution system.

In January 2026, the NJBPU approved the merger of Pinelands into Middlesex through a corporate reorganization.

In addition to above, Middlesex is currently recovering costs associated with its Lead Service Line Replacement Plan, prior DISC eligible investments and purchased water.

Tidewater - In July 2025, the DEPSC approved a $5.5 million base rate increase for Tidewater, effective July 3, 2025.

In addition to the above, Tidewater is currently recovering costs associated with DSIC investments and Tidewater's obligation to identify and inventory lead service lines.

For additional information on these rate matters, see Note 2, Rate and Regulatory Matters.

Water and Wastewater Quality and Environmental Regulations

Government environmental regulatory agencies regulate our operations in New Jersey and Delaware with respect to water supply, treatment and distribution systems and the quality of the water. They also regulate our operations with respect to wastewater collection, treatment and disposal.

Regulations relating to water quality require us to perform tests to ensure our water meets state and federal quality requirements. We participate in industry-related research to identify technologies that may reduce the level of organic, inorganic and synthetic compounds found in water. The cost to water utilities to comply with any proposed water quality standards depends in part on the limits set in the regulations and on the method selected to treat the water to the required standards. We regularly test our water to determine compliance with government environmental regulatory agencies’ water quality standards.

In April 2024, the USEPA finalized drinking water regulations for Perfluoroalkyl Substances (PFAS), establishing maximum contaminant levels (MCLs) for three PFAS compounds (Regulated PFAS) that are lower than the current NJDEP MCLs adhered to by the Company. Under the new USEPA regulations effective April 2024, water systems must monitor for Regulated PFAS and have three years to complete initial monitoring (by April 2027), followed by ongoing compliance monitoring. Water systems must also provide the public with information on the levels of Regulated PFAS in their drinking water beginning in 2027. Delaware law requires all water systems to notify their customers beginning in 2026 if PFAS levels exceed the proposed EPA MCL. Water systems have five years (by April 2029) to implement treatment solutions if monitoring shows that drinking water levels exceed these MCLs. The USEPA has announced its plans to issue a proposed rule extending the compliance date to 2031, however currently no rule has been published.

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Beginning in April 2029 and absent an extension by the USEPA, water systems that have Regulated PFAS in drinking water which exceeds one or more of these MCLs must take action to comply with the USEPA rule and must provide notification to the public of the violation.

In anticipation of these new USEPA standards, in 2023, the Company began implementing its strategy to meet these lower MCLs for Regulated PFAS and is finalizing preliminary engineering studies and has begun preliminary design of for PFAS treatment at the Company's largest water treatment facility in New Jersey to ensure that effective PFAS treatment approaches are implemented. Similarly, in Delaware the Company currently treats for PFAS at four locations and is implementing a strategy to treat at other locations as needed to ensure compliance with the new regulation.

We treat the groundwater supplies in our Middlesex System with chlorination for primary disinfection purposes and use air stripping for removal of volatile organic compounds. In addition, we use granular activated carbon filtration for Regulated PFAS compounds treatment.

Surface water treatment in our Middlesex System is by conventional treatment; coagulation, sedimentation and filtration. The treatment process includes pH adjustment, ozone and chlorination for disinfection, and corrosion control for the distribution system.

Treatment of groundwater in our Tidewater System is by chlorination for disinfection purposes, ion exchange for PFAS treatment and, in some cases, pH adjustment and filtration for nitrate and iron removal. Chloramination is used for final disinfection at Southern Shores and at a Tidewater plant.

Treatment of groundwater in the Pinelands Water System (primary disinfection only) is performed at individual well sites.

Treatment of wastewater in the Pinelands Wastewater System includes the use of rotating biological contactors.

The NJDEP and DEDPH monitor our activities and review the results of water quality tests that are performed for adherence to applicable regulations. Other applicable regulations include the Lead, Copper and Lead Service Line Rules, the Federal Surface Water Treatment Rule and the Federal Total Coliform Rule and regulations for maximum contaminant levels established for various volatile organic compounds.

The Company must comply with various environmental laws and regulations promulgated by the USEPA, NJDEP and other governmental agencies, including the Toxic Catastrophe Prevention Act, the Spill Prevention, Control, and Countermeasure Rule and the Discharge Prevention Program of the New Jersey Spill Compensation and Control Act.

Seasonality

Customer demand for our water during the warmer months is generally greater than other times of the year due primarily to additional consumption of water in connection with irrigation systems, swimming pools, cooling systems and other outside water use. Throughout the year, and particularly during typically warmer months, demand may vary with temperature and rainfall timing and overall levels. In the event that temperatures during the typically warmer months are cooler than normal, or if there is more rainfall than normal, the customer demand for our water may decrease and therefore, adversely affect our revenues.

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Management

This table lists information concerning our executive management team:

Nadine Leslie – Ms. Leslie joined the Company as President and Chief Executive Officer in March 2024. Ms. Leslie is an accomplished leader with more than 25 years of domestic and international experience in the Water Industry. She previously served as Chief Executive Officer of Suez North America from 2019 to 2022. Ms. Leslie holds a Bachelor of Science degree in civil engineering from the Faculte des Sciences in Haiti and completed an internship/scholarship program in urban planning at La Cambre University in Belgium. Ms. Leslie currently serves as a Director on the Board of Directors of Provident Financial Services, Inc. (since June 2021), Hackensack Meridian Health (since July 2020) and Syensqo SA/NV (from December 2023 through July 2025).

Mohammed G. Zerhouni – Mr. Zerhouni, a Certified Public Accountant, joined the Company in June 2024 as Senior Vice President, Chief Financial Officer and Treasurer. He was most recently the Senior Vice President of Finance and Principal Accounting Officer of SJW Group. Prior to joining SJW Group, he was the Chief Financial Officer for Veolia North America’s regulated utility business. Mr. Zerhouni served in various roles of increasing responsibility up to Senior Manager in the audit practice of PricewaterhouseCoopers LLP. Mr. Zerhouni attended Franklin University, where he received a Bachelor of Science in Accounting and a Masters in Business Administration.

Gregory S. Sorensen - Mr. Sorensen joined the Company in December 2024 as Vice President and Chief Operating Officer. Prior to joining the Company, Mr. Sorensen served as President, West Region at Liberty Utilities where he led a team of 800 professionals delivering safe and reliable water, wastewater, and electric service in Arizona, California, Texas and Chile. At Liberty, Mr. Sorensen had nearly 20 years of progressive leadership roles including in accounting, customer service, engineering, operations and general management. Before joining Liberty, Mr. Sorensen worked in various roles in accounting and finance for an international call center company in Arizona and in public accounting in North Carolina and Georgia. Mr. Sorensen attended Wake Forest University where he received a Bachelor of Science in Accounting.

Robert K. Fullagar – Mr. Fullagar, a licensed professional engineer and New Jersey T4 and W4 Licensed Operator, joined the Company in 1997, was named Assistant Vice President-Operations in January 2019 and promoted to Vice President-Operations in July 2019. In February 2025, Mr. Fullagar was promoted to President-New Jersey Operations. Mr. Fullagar attended the New Jersey Institute of Technology, where he received a Bachelor of Science Degree in Civil Engineering. Mr. Fullagar serves as Sector Chair of the New Jersey Infrastructure Advisory Committee and is a Member of the NJDEP’s Licensed Operator Advisory Committee.

Lorrie B. Ginegaw – Ms. Ginegaw joined Tidewater in 2004 and in 2007 was promoted to Director of Human Resources for Middlesex. In March 2012, Ms. Ginegaw was named Vice President-Human Resources. Prior to joining the Company, Ms. Ginegaw worked in various human resources positions in the healthcare and transportation/logistics industries and is a Society for Human Resource Management Certified Professional. Ms. Ginegaw attended Wichita State University, where she received a Bachelor of Arts in Field Studies, Business and Psychology, and Wilmington University, where she received a Master’s in Business Administration. Ms. Ginegaw serves as a volunteer director on the Board of the New Jersey Utilities Association.

Jay L. Kooper – Mr. Kooper joined the Company in 2014 as Vice President and General Counsel and serves as Secretary for the Company and all subsidiaries. Prior to joining the Company, Mr. Kooper held various positions in private and public entities as well as in private law practice, representing electric, gas, water, wastewater, telephone and cable companies as well as municipalities and private clients before 17 state public utility commissions and legislatures, federal agencies and federal and state appellate courts. Mr. Kooper serves as a volunteer director on selected non-profit utility industry-related Boards including the New Jersey State Bar Association’s Public Utility Law Section (current Consulter and Past Chairman) and serves as the Chairman of the National Association of Water Companies’ New Jersey Chapter. Mr.

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Kooper also serves on other non-profit boards based in New Jersey, including as President of Temple B’Nai Abraham in Livingston, New Jersey and as a Director of the Crohn’s and Colitis Foundation’s New Jersey Chapter.

Georgia M. Simpson – Ms. Simpson joined the Company in 2009, was named Assistant Vice President-Information Technology in January 2019 and promoted to Vice President- Information Technology in July 2019. In April 2022, Ms. Simpson was named Chief Technology Officer. Prior to joining the Company, Ms. Simpson held various Information Technology positions and has gained an extensive array of technical and business computer certifications. Ms. Simpson graduated from Monroe University in New York with a Bachelor’s Degree in Information Systems. Ms. Simpson serves as a member of the Delaware Cyber Security Advisory Council, the Society for Information Management, New Jersey chapter and the Project Management Institute, New Jersey chapter.

Bruce E. Patrick – Mr. Patrick, a licensed professional engineer, joined Tidewater in February 2002 as Vice President of Engineering. He was promoted to Vice President and General Manager in April 2012, Executive Vice President in April 2023, and President in December 2023. Mr. Patrick has extensive experience in regulatory compliance, permitting, planning and design. Prior to joining Tidewater, he served as Kent County, Delaware Public Works Director and County Engineer where he had overall responsibility for the County’s regional wastewater facilities. Mr. Patrick also held prior positions with the Delaware Department of Natural Resources and Environmental Control as well as the Delaware Division of Public Health.

Robert J. Capko – Mr. Capko, a Certified Public Accountant, joined the Company in 2009 as Corporate Controller. On March 28, 2023, Mr. Capko was appointed Principal Accounting Officer of Middlesex. Mr. Capko is also a Director and Treasurer of Tidewater and White Marsh and Controller of USA, USA-PA, Pinelands Water and Pinelands Wastewater. Prior to joining Middlesex, Mr. Capko was an Audit Senior Manager with Deloitte & Touche LLP, with a focus on publicly traded regulated utilities including several regulated public utility clients subject to the jurisdiction of the NJBPU. Mr. Capko serves as the Treasurer of the National Association of Water Companies’ New Jersey Chapter.