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WaterSafety

Surface Water — Water Systems

Water systems sourced from rivers, lakes, and reservoirs. Surface water requires more treatment but serves most large cities.

158
Systems
66,515,334
People Served
82/100
Avg Score
68
Grade A Systems
Surface WaterGround WaterMixed Sources

Surface Water Systems (158)

Chicago

Chicago, Illinois

2,746,388 people
C

San Antonio Water System

San Antonio, Texas

2,113,151 people
B

Washington Suburban Sanitary Commission

Laurel, Maryland

1,900,000 people
A

Phoenix City Of

Phoenix, Arizona

1,695,000 people2 violations
D

Philadelphia Water Department

Philadelphia, Pennsylvania

1,600,000 people
C

City of Baltimore

Baltimore, Maryland

1,600,000 people3 violations
F

Las Vegas Valley Water District

Las Vegas, Nevada

1,539,277 people
B

East Bay MUD

Oakland, California

1,442,800 people
A

Dallas Water Utility

Dallas, Texas

1,356,479 people
A

Cleveland Public Water System

Cleveland, Ohio

1,308,955 people
C

Columbus Public Water System

Columbus, Ohio

1,305,946 people3 violations
F

Denver Water Board

Denver, Colorado

1,287,000 people
C

Charlotte Water

Charlotte, North Carolina

1,163,701 people
A

Fairfax County Water Authority

Herndon, Virginia

1,121,613 people
A

Mo American St Louis St Charles Counties

Chesterfield, Missouri

1,111,000 people
A

Atlanta

Atlanta, Georgia

1,089,893 people5 violations
F

Gwinnett Co. Dept. of Water Resources

Lawrenceville, Georgia

975,000 people
A

Citizens Water - Indianapolis

Indianapolis, Indiana

880,345 people
B

Aqua Pa Main System

Bryn Mawr, Pennsylvania

822,600 people2 violations
F

Veolia Water New Jersey Hackensack

Haworth, New Jersey

792,713 people1 violation
C

Metro Water Services

Nashville, Tennessee

778,153 people
B

Louisville Water Company

Louisville, Kentucky

764,769 people
A

Cincinnati Public Water System

Cincinnati, Ohio

750,200 people
A

Dekalb County

Decatur, Georgia

743,000 people
A

Cobb County

Marietta, Georgia

695,000 people
A

Boston Water and Sewer Commission (mwra)

Boston, Massachusetts

675,647 people1 violation
B

Portland Water Bureau

Portland, Oregon

666,200 people1 violation
C

Metropolitan Utilities District

Omaha, Nebraska

660,000 people
B

Oklahoma City

Oklahoma City, Oklahoma

644,000 people
A

Raleigh, City Of

Raleigh, North Carolina

640,000 people
B

Detroit City Of

Detroit, Michigan

633,218 people
A

Milwaukee Waterworks

Milwaukee, Wisconsin

626,000 people
A

Central Alabama Water System

Birmingham, Alabama

585,000 people
B

Albuquerque Water System

Albuquerque, New Mexico

560,326 people
A

City of Fresno

Fresno, California

545,716 people
A

Aurora City Of

Aurora, Colorado

533,407 people
B

Kansas City Pws

Kansas City, Missouri

513,800 people1 violation
C

Mcwa

Rochester, New York

496,753 people1 violation
B

Water District 1 of Johnson Co

Kansas City, Kansas

482,000 people
A

Mesa City Of

Mesa, Arizona

466,000 people
C

Colorado Springs Utilities

Colorado Springs, Colorado

464,111 people
B

Truckee Meadows Water Authority

Reno, Nevada

442,000 people
A

Virginia Beach, City Of

Virginia Beach, Virginia

437,994 people
A

North Fulton County

Alpharetta, Georgia

434,517 people
B

Minneapolis

Minneapolis, Minnesota

425,300 people
A

Regional Water Authority

New Haven, Connecticut

418,900 people
B

Tulsa

Tulsa, Oklahoma

413,000 people
B

Newport News, City Of

Newport News, Virginia

407,300 people
A

Greenville Water (2310001)

Greenville, South Carolina

396,265 people
A

Wichita, City Of

Wichita, Kansas

395,699 people
A

Saint Paul Regional Water Services

St. Paul, Minnesota

392,529 people
C

Metropolitan District Commission

Hartford, Connecticut

390,887 people
A

Chesterfield Co Central Water System

Chesterfield, Virginia

389,897 people
A

Winston-Salem, City Of

Pfafftown, North Carolina

388,060 people
C

Salt Lake City Water System

Salt Lake City, Utah

381,174 people2 violations
F

North Las Vegas Utilities

North Las Vegas, Nevada

376,515 people
A

Central Arkansas Water

Little Rock, Arkansas

368,455 people
A

Aquarion-Eastern Fairfield County

Shelton, Connecticut

351,756 people
C

Alameda County Water District

Fremont, California

344,000 people
A

Henderson City Of

Henderson, Nevada

336,534 people
A

Ecwa Direct

Buffalo, New York

335,000 people
A

New Orleans Carrollton Water Works

New Orleans, Louisiana

334,903 people2 violations
F

Loudoun Water - Central System

Ashburn, Virginia

334,808 people
B

Charleston Water System (sc1010001)

Charleston, South Carolina

327,422 people
A

Durham, City Of

Durham, North Carolina

322,083 people
C

Greensboro, City Of

Greensboro, North Carolina

319,588 people
C

Columbia City of (sc4010001)

Columbia, South Carolina

319,500 people3 violations
F

Bellevue City Of

Bellevue, Washington

317,330 people
A

St Louis City Pws

St Louis, Missouri

304,709 people
B

Kentucky-American Water Co

Lexington, Kentucky

299,501 people
A

Newark Water Department

Newark, New Jersey

294,274 people22 violations
F

Cocoa, City Of

Cocoa, Florida

294,039 people1 violation
C

City of Plano

Plano, Texas

292,059 people
A

Howard County D.p.w. Distribution

Columbia, Maryland

286,158 people
B

Mobile, Bd. Of W&s Comm. Of the City Of

Mobile, Alabama

279,000 people4 violations
F

Buffalo Water Authority

Buffalo, New York

276,000 people
B

Montgomery (ww&ssb of the City Of)

Montgomery, Alabama

276,000 people
A

E Jefferson Ww District 1

Jefferson, Louisiana

275,163 people
A

Grand Rapids

Grand Rapids, Michigan

273,005 people
A

Fort Wayne - 3 Rivers Filtration Plant

Fort Wayne, Indiana

269,994 people3 violations
F

CWS - Bakersfield

San Jose, California

267,881 people
A

Nj American Water - Western

Delran, New Jersey

264,586 people
C

Huntsville Utilities

Huntsville, Alabama

262,158 people
A

Jersey City Mua

Hoboken, New Jersey

262,000 people1 violation
C

Knoxville Utilities Board - Kub

Knoxville, Tennessee

254,671 people
B

Clarksville Water Department

Clarksville, Tennessee

251,864 people
A

City of Garland

Garland, Texas

248,822 people
B

Gilbert, Town Of

Gilbert, Arizona

247,600 people3 violations
F

Gsw&sa (sc2620004)

Conway, South Carolina

247,550 people
A

Chandler City Of

Chandler, Arizona

247,328 people1 violation
D

Des Moines Water Works

Des Moines, Iowa

246,055 people2 violations
D

Ann Arbor

Ann Arbor, Michigan

241,868 people
B

City of Frisco

Frisco, Texas

231,910 people
A

Thornton City Of

Thornton, Colorado

226,465 people
C

Tualatin Valley Water District

Beaverton, Oregon

224,600 people
B

Everett Public Works Dept. City Of

Everett, Washington

215,774 people
A

Rochester City

Rochester, New York

214,000 people1 violation
B

Tennessee American Water

Chattanooga, Tennessee

211,499 people
A

Springfield Pws

Springfield, Missouri

210,898 people
B

Indiana American Water - Northwest

Greenwood, Indiana

210,510 people
A

Wvawc-Kanawha Valley Dist

Charleston, West Virginia

209,283 people
B

Worcester Dpwp, Water Supply Division

Worcester, Massachusetts

206,518 people
A

Westminster City Of

Westminster, Colorado

202,078 people
B

Alderwood Water District

Lynnwood, Washington

200,000 people
A

Salem Public Works

Salem, Oregon

199,820 people
B

Northern Kentucky Water District

Ft. Thomas, Kentucky

199,460 people
B

Contra Costa Water District

Concord, California

198,000 people
A

Shreveport Water System

Shreveport, Louisiana

192,378 people76 violations
F

City of Jackson

Jackson, Mississippi

189,673 people100 violations
F

Aurora

Aurora, Illinois

183,000 people
A

Evansville Water Utility

Evansville, Indiana

182,444 people
A

Eugene Water & Electric Board

Eugene, Oregon

176,000 people
A

Springfield Water and Sewer Commission

Springfield, Massachusetts

167,954 people27 violations
F

Tuscaloosa Water & Sewer

Tuscaloosa, Alabama

166,524 people6 violations
F

Kent Water Department

Kent, Washington

166,421 people
A

Redmond Water System City Of

Redmond, Washington

163,335 people
A

Naperville

Naperville, Illinois

156,406 people
B

Del-Co Water Company, INC.

Delaware, Ohio

150,000 people
A

Iowa-American Wtr Co-Davenport

Davenport, Iowa

147,720 people
A

Bjw&sa (0720003)

Okatie, South Carolina

145,634 people4 violations
F

Olathe, City Of

Olathe, Kansas

143,014 people
B

Chester Water Authority

Chester, Pennsylvania

140,437 people
A

Pa Amer Water Co Lake Scranton

Wilkes Barre, Pennsylvania

134,570 people
A

Clermont Public Water System

Batavia, Ohio

133,059 people2 violations
F

Topeka, City Of

Topeka, Kansas

125,963 people1 violation
D

Granger-Hunter Improvement District

Salt Lake City, Utah

121,083 people
B

Aquarion-Stamford

Shelton, Connecticut

119,214 people
B

Cambridge Water Department

Cambridge, Massachusetts

118,214 people
A

West Jordan City Water System

West Jordan, Utah

117,025 people
B

Fayetteville Waterworks

Fayetteville, Arkansas

116,398 people
A

Broken Arrow Municipal Authority

Broken Arrow, Oklahoma

116,330 people
B

Provo City

Provo, Utah

116,288 people
B

Lowell Regional Water Utility

Lowell, Massachusetts

115,000 people3 violations
F

Green Bay Waterworks

Green Bay, Wisconsin

107,369 people
B

Rio Rancho Water & Ww Services

Rio Rancho, New Mexico

107,350 people
B

Waterbury Water Department

Waterbury, Connecticut

107,271 people
C

Medford Water Commission

Medford, Oregon

106,068 people
B

St George City Water System

St George City, Utah

105,240 people
C

Racine Waterworks

Racine, Wisconsin

105,100 people
A

Norman Utilities Authority

Norman, Oklahoma

104,868 people1 violation
C

Harford County D.p.w.

Abingdon, Maryland

104,567 people
B

Kenosha Water Utility

Kenosha, Wisconsin

99,218 people
A

Springdale Water Utilities

Springdale, Arkansas

98,948 people
A

Wvawc - Huntington Dist

Charleston, West Virginia

98,647 people
C

Lawton

Lawton, Oklahoma

92,757 people
B

North Penn Water Authority

Lansdale, Pennsylvania

91,941 people
A

Bloomington

Bloomington, Minnesota

91,300 people
A

Warren County Water District

Bowling Green, Kentucky

91,118 people
B

Santa Fe Water System (city Of)

Santa Fe, New Mexico

90,810 people1 violation
D

Fort Smith Water Utilities

Fort Smith, Arkansas

86,209 people1 violation
C

Cicero

Cicero, Illinois

83,000 people1 violation
C

Rogers Water Utilities

Rogers, Arkansas

81,443 people
A

Hardin County Water District #2

Elizabethtown, Kentucky

76,326 people
C

Ankeny, City Of

Ankeny, Iowa

76,207 people
A

Morgantown Utility Board

Morgantown, West Virginia

64,644 people
A

Carson City Public Works

Carson City, Nevada

59,000 people
B

Beckley Water Company

Beckley, West Virginia

47,386 people
A

Berkeley County Pswd-Potomac River

Martinsburg, West Virginia

34,786 people
C

Frequently Asked Questions

158 tracked water systems use surface water as their primary source, serving a total of 66,515,334 people. The average Water Safety Score for these systems is 82/100.

Surface water from rivers and reservoirs requires extensive treatment (filtration, disinfection) before it is safe to drink. It is more susceptible to contamination from runoff, agricultural activity, and industrial discharge. However, well-treated surface water can be very safe.

Water source type is classified by the EPA in the Safe Drinking Water Information System (SDWIS). Systems report whether they draw primarily from surface water (rivers, lakes, reservoirs), ground water (wells, aquifers), or a mix of both.