Lake Washington, Melbourne's Drinking-Water Lake

Lake Washington is a natural lake in the upper St. Johns River marshes of Brevard County and the source of raw water for the City of Melbourne's surface water treatment plant.

The City of Melbourne's water treatment page calls it the third uppermost of the naturally connected upper St. Johns River lakes and one of the few surface water supplies of drinking water in Florida. Water pumped from the lake is treated at the John A. Buckley Surface Water Treatment Plant.

The lake sits inside public conservation land. The St. Johns River Water Management District's River Lakes Conservation Area takes in lakes Washington, Winder and Poinsett, land the District acquired as part of the Upper St. Johns River Basin Project it undertook jointly with the U.S. Army Corps of Engineers. Wetlands there are typically dominated by sawgrass, smartweed, arrowhead and maidencane, and the District lists wood storks, bald eagles, Florida sandhill cranes and river otters among the listed species using the area near Lake Washington.

The Florida Fish and Wildlife Conservation Commission's Brevard County fishing guide describes a 60-mile stretch of the St. Johns River headwaters that flows through lakes from 350 to 4,500 acres, including Lake Hell'n Blazes, Lake Sawgrass, Lake Washington, Lake Winder and Lake Poinsett. FWC notes that water levels fluctuate around six feet a year between the dry winter and spring and the wet late summer and early fall, and that most of the upper river and lakes are surrounded by state-owned land.

Melbourne depends on Lake Washington because the lake is the raw water source for the Buckley surface water plant, one of the city's two water treatment facilities.

The other plant draws from underground. The City of Melbourne says its Joe Mullins Reverse Osmosis Water Treatment Plant went into operation in 1995 with a capacity of 5 million gallons per day and a 4 million gallon ground water storage tank, and takes raw water from four Floridan Aquifer wells about 650 to 850 feet underground, each yielding about 3.1 million gallons per day. The city's treatment page does not state what share of Melbourne's supply comes from each plant.

The lake's reach extends well past the city limits. Melbourne's utility supplies drinking water to Melbourne, Melbourne Beach, Indialantic, Indian Harbour Beach, Satellite Beach, Palm Shores, Melbourne Village and unincorporated Brevard County south of the Pineda Causeway, and provides wholesale water service to West Melbourne, so the system fed partly by Lake Washington reaches from the mainland to the barrier island.

Keeping that water fresh in the pipes is its own task. The City of Melbourne says about 100 automatic flushing valves are placed throughout its distribution system to maintain water quality across what it calls a vast network, a reminder that water drawn from Lake Washington travels a long way before it reaches a tap in Satellite Beach or Palm Shores.

Lake Washington's level is held up by a fixed-crest weir just north of the lake, the one point where SJRWMD regulates St. Johns River flow in the River Lakes area to help ensure Melbourne's water supply.

Upstream of Lake Washington, the marshes of the Upper St. Johns River Basin Project, which surround the River Lakes land, act as storage for the river. In an October 2016 release, SJRWMD said the nearly 200,000-acre project has revitalized the river's flow by reclaiming drained marshlands, improving water quality, providing for water supply, and restoring or enhancing wetland habitat, benefits that reach the lake Melbourne draws from.

The river is measured just downstream. The U.S. Geological Survey's St. Johns River near Melbourne gage drains 968 square miles of the upper St. Johns, has daily data from October 1939 and is operated in cooperation with the District. Its record of peak measurements runs from September 1940 to October 2024, continuous data begin in October 1993, and field measurements continued into July 2026. The same record holds discrete water samples from 1952 to 1988 covering 184 observed properties, an early chemistry archive for the river that Melbourne pumps from.

Natural swings still matter. FWC says water levels in the upper St. Johns fluctuate around six feet a year, enough to turn a river less than 150 feet wide into a floodplain several miles across, which changes both navigation and where fish gather around Lake Washington. The river runs in a single channel down to Cocoa before it braids into multiple channels.

FWC says Lake Washington anglers can find bream, crappie, largemouth bass and catfish, and SJRWMD lists wood storks, bald eagles, Florida sandhill cranes and river otters on the surrounding conservation land.

FWC's guide adds that shore anglers may have luck fishing for bass and bream around the pads and bulrushes, and that during high water the edges of overhanging and floating vegetation in the middle river between Poinsett and Winder, and south of Lake Washington, are good places to start. The agency notes that the river is not marked for navigation through this stretch.

SJRWMD describes the River Lakes area near Lake Washington as important habitat for fish and wildlife populations and a recreational resource for anglers, hunters, boaters and bird-watchers. Eastern meadowlarks are plentiful on the property, which has open vistas dotted with palms, seasonal wildflowers and grasslands that change color with the seasons, and visitors may also encounter cattle.

Yes, the public can reach Lake Washington by boat from ramps on State Road 520, U.S. 192 and at Lake Washington County Park, or by land through a River Lakes gate on Wickham Road.

SJRWMD lists picnic pavilions, restrooms, a fishing pier and boat, canoe and airboat ramps at Lake Washington County Park, and FWC places the park on the east side of the lake with a boat ramp, fishing pier, restrooms, pavilions and parking. Primitive campsites along the river are reachable by boat, two day-use shelters stand in the conservation area, and more than 7 miles of trails cross the River Lakes land.

SJRWMD publishes GPS coordinates for the River Lakes campsites and shelters, among them Deepwater Campsite, Buzzard's Roost Camp, Pontoon Camp, Mallow Point Camp, Palms Camp, Highwater Camp, Lake Poinsett Camp, Spike Camp, Wolf's Head Camp and Persimmon Mound Camp, plus the Poinsett and Oak Trees shelters and a Mud Lake observation tower. The shelters are for day use only, for picnicking or protection from the weather, and parts of the hiking trail are unshaded while others pass through dense hardwood and palm hammocks in the River Lakes area around Lake Washington.

The land entrance sits at the western terminus of Wickham Road. The District opens that gate at 7 a.m. and closes it promptly at 7 p.m. each day, and the designated parking area lies about 3 miles, or a 15-minute drive, west of the gate. Most of the property falls within the Upper St. Johns River Marsh Wildlife Management Area, where hunting is allowed, along with fishing, hiking, bicycling, primitive camping, canoeing, boating and wildlife viewing near Lake Washington.

Last verified: October 15, 2026, with the City of Melbourne water treatment page, SJRWMD's River Lakes Conservation Area page and 2016 Upper Basin release, FWC's Upper St. Johns River and Lakes fishing guide and the USGS gage record.