Which US City Uses The Most Water

New York City is the largest municipal water consumer in the United States, using about one billion gallons every day within its five boroughs. That demand reflects the needs of more than eight million people, thousands of businesses, hospitals, schools, and millions of annual visitors. Supplying that much water takes a vast system of infrastructure, conservation programs, and watershed protection.

One Billion Gallons Of Water Used Every Day

New York City's water consumption stands out even among America's largest urban centers. According to the city's Department of Environmental Protection (DEP), 363.4 billion gallons of drinking water were delivered within the five boroughs in 2025. That represents an average of one billion gallons every day. The city's water system supplied another 39 billion gallons to 70 communities and institutions outside its boundaries, bringing total annual deliveries to 402.4 billion gallons.

The distinction between city consumption and regional deliveries is important. New York's water system serves more than 8.5 million city residents and over one million people in surrounding counties, including Westchester, Putnam, Orange, and Ulster. The one-billion-gallon figure refers specifically to water delivered within New York City, highlighting the municipality's own demand.

How New York Compares To Other Cities

For perspective, one million gallons can fill 1.5 Olympic-sized swimming pools, so New York uses about 1,500 pools of water every day.

Comparing cities is not straightforward, because utilities report their water use in different ways. Chicago's Department of Water Management delivers about 750 million gallons a day, but that figure covers Chicago and its suburbs. Houston's utility produces about 516 million gallons daily for a service area reaching well beyond the city limits. No single national ranking measures every city the same way. Even so, the one billion gallons New York delivers within its own five boroughs is larger than the regional totals reported by either city, a gap that makes New York the country's largest municipal water user.

That volume starts far beyond the city streets, in protected watersheds and reservoirs scattered throughout the Hudson Valley and Catskill Mountains.

New York's Major Reservoir

Ashokan Reservoir is one of the most important components of New York City's drinking water system. Located in Ulster County, about 70 miles north of the city, it was created by damming Esopus Creek and entered into service in 1915. The reservoir consists of two basins separated by a concrete dividing weir and has a storage capacity of about 123 billion gallons. Along with Schoharie Reservoir, it forms part of the Catskill water supply system, the source of almost 40 percent of New York City's daily potable water.

The water travels a long way before reaching a New York City faucet. From Ashokan, it passes through the 92-mile Catskill aqueduct to Kensico Reservoir in Westchester County. The aqueduct relies on gravity, moving huge volumes of water across the landscape without conventional pumping.

A Vast Water Collection Network

Ashokan is one part of a much larger water collection network. New York City owns 19 reservoirs and controls three additional lakes across a watershed covering 1,972 square miles. Extending as far as 125 miles from the city, the system is divided into three major supply networks, the Catskill, Delaware, and Croton systems.

The Delaware system is the largest contributor, supplying about half of the city's drinking water. Its four reservoirs include Pepacton, Cannonsville, Neversink, and Rondout. Pepacton, the largest of them, holds about 143.7 billion gallons at full capacity. The Catskill system contributes almost 40 percent, and the Croton system normally supplies the remaining 10 percent.

The Croton system is the oldest of the three. Its origins date to the 19th century, when New York began looking beyond its immediate surroundings for a dependable drinking water supply. The old Croton reservoir entered service in 1842, and the system eventually expanded to include multiple reservoirs and controlled lakes. Unlike the Catskill and Delaware supplies, Croton water passes through a filtration plant in the Bronx before entering the city's distribution network.

New York City is one of five large American cities that do not conventionally filter their primary Catskill and Delaware surface water supplies. Instead, the water undergoes disinfection and ultraviolet treatment, and extensive watershed protection helps prevent contamination at its source.

Where All That Water Goes

With a billion gallons delivered within the city every day, demand extends well beyond household taps and showers. According to New York's DEP, bathrooms account for about 50 to 75 percent of residential indoor water use. Older toilets can consume between 4.5 and 7 gallons per flush, compared with 1.28 gallons or less for modern high-efficiency models.

Commercial and institutional users add substantially to the city's overall demand. Hotels, restaurants, hospitals, schools, office buildings, and industrial facilities all require dependable water supplies. New York's large hospitality industry alone involves thousands of establishments providing accommodation, food, laundry, and other services to residents and visitors. Municipal operations require water for public facilities, street cleaning, parks, and firefighting.

The city's water demand fluctuates throughout the day. Morning showers, restaurant preparation, commercial cleaning, and evening household activities all contribute to changing consumption patterns. Hillview Reservoir in Yonkers plays an important role in managing these variations, acting as a balancing reservoir before water enters the city's distribution network.

One distinctly New York feature is the scale of its underground infrastructure. Approximately 7,000 miles of aqueducts, tunnels, and water mains carry drinking water throughout the five boroughs. The distribution network is complemented by an extensive wastewater system that collects used water and sends it to treatment facilities before its eventual return to the environment.

Reducing New York's Water Consumption

Despite its high demand, New York City has made real progress in reducing water consumption. Average daily water use peaked at about 1.5 billion gallons in 1979. Today, demand is about 35 percent lower, even though the city's population has grown by more than 1.3 million people since 1980. The DEP describes New York as one of the most water-efficient large cities in the country.

A range of initiatives have contributed to the reduction. The city replaced thousands of inefficient toilets, encouraged water-saving plumbing fixtures, improved water metering, and introduced automated leak notifications. These measures help residents and businesses identify unnecessary consumption and repair problems before substantial quantities of water are wasted.

Leak detection matters most in a city with thousands of miles of aging underground infrastructure. The DEP surveyed 2,250 miles of water mains in 2025 and estimated that proactive leak repairs saved about 9.8 million gallons of water per day.

The DEP shares conservation advice to New Yorkers as well. Shorter showers, efficient washing machines, low-flow shower heads, and repairing dripping faucets can all reduce household consumption. A slowly leaking faucet can waste 15 to 20 gallons every day, illustrating how seemingly minor problems add up across millions of households.

Protecting New York City's Future Water Supply

New York's water demand makes protecting its distant watersheds as important as maintaining the infrastructure that delivers water to the city. The reservoirs depend on healthy forests, streams, wetlands, and surrounding landscapes to maintain water quality and replenish supplies. Development, agricultural runoff, pollution, and changing precipitation patterns can all affect the system.

The city invests more than $100 million annually in watershed protection programs, including land conservation, wastewater improvements in surrounding communities, and agricultural pollution prevention. Because the Catskill and Delaware systems do not employ filtration, preventing contamination at the source is important.

Climate change adds another challenge. Extended dry periods can reduce reservoir levels and place pressure on the entire supply network. New York's extensive reservoir system provides some flexibility, but long-term reliability still depends on careful management and responsible consumption. Protecting the watersheds and maintaining the city's aging infrastructure will remain a priority as precipitation patterns become increasingly unpredictable.

Managing A Finite Resource

New York City uses more water than any other US city, about one billion gallons a day within its five boroughs. A network of 19 reservoirs and three controlled lakes, stretching as far as 125 miles into the Catskills and Hudson Valley, makes that volume possible. The city uses far less than it once did, with demand about 35 percent below its 1979 peak, even as its population has grown. Keeping the country's largest municipal water supply reliable will depend on protecting those distant watersheds and continuing to cut waste at home.