Water Quality in Maryland
461 water systems • 146 cities • EPA SDWIS Data
461
Water Systems
5,321
Total Violations
594
Health-Based Violations
5,523,173
Population Served
Overview
Maryland ranks 44th among all U.S. states for total drinking water violations, out of 51 states tracked. The state has 5,321 EPA Safe Drinking Water Act violations on record across 461 water systems serving 146 cities. Of those, 594 are health-based violations, meaning a regulated contaminant was measured above the EPA-established safe level. Maryland's total violation count is 85% below the national average. Water systems in Maryland serve approximately 5,523,173 people. The most frequently cited contaminants in Maryland violations include Gross Alpha, Stage 2 DBP, Nitrate, Total Coliform (TCR), Fecal Coliform.
Cities with Most Violations in Maryland
| # | City | Violations | Health-Based | Water Systems | Population |
|---|---|---|---|---|---|
| 1 | Port Deposit | 230 | 6 | 7 | 1,187 |
| 2 | Princess Anne | 217 | 1 | 2 | 4,050 |
| 3 | Frederick | 200 | 12 | 19 | 147,122 |
| 4 | Tylerton | 188 | 5 | 5 | 409 |
| 5 | La Plata | 179 | 2 | 19 | 106,661 |
| 6 | Waldorf | 160 | 6 | 18 | 3,332 |
| 7 | California | 158 | 0 | 28 | 59,957 |
| 8 | Elkton | 141 | 23 | 5 | 18,405 |
| 9 | Havre De Grace | 109 | 11 | 3 | 14,555 |
| 10 | Millersville | 94 | 7 | 14 | 387,543 |
Largest Cities in Maryland
| # | City | Population | Violations | Water Systems |
|---|---|---|---|---|
| 1 | Laurel | 1,900,000 | 0 | 1 |
| 2 | Baltimore | 1,601,584 | 87 | 7 |
| 3 | Millersville | 387,543 | 94 | 14 |
| 4 | Columbia | 286,458 | 31 | 2 |
| 5 | Frederick | 147,122 | 200 | 19 |
| 6 | La Plata | 106,661 | 179 | 19 |
| 7 | Abingdon | 104,567 | 9 | 1 |
| 8 | Hagerstown | 94,933 | 49 | 6 |
| 9 | Westminster | 62,913 | 64 | 6 |
| 10 | Fort Meade | 62,234 | 1 | 1 |
All Cities in Maryland
| City | Population | Violations | Health Violations | Contaminants |
|---|---|---|---|---|
| Laurel | 1,900,000 | 0 | 0 | |
| Baltimore | 1,601,584 | 87 | 7 | E. coli, Stage 2 DBP, Total Haloacetic Acids (HAA5) |
| Millersville | 387,543 | 94 | 7 | Chromium, Stage 2 DBP |
| Columbia | 286,458 | 31 | 8 | Barium |
| Frederick | 147,122 | 200 | 12 | Bromate, E. coli, Stage 2 DBP +2 more |
| La Plata | 106,661 | 179 | 2 | Disinfection Byproducts |
| Abingdon | 104,567 | 9 | 0 | |
| Hagerstown | 94,933 | 49 | 5 | Bromate, Chlorine Dioxide, Disinfection Byproducts +2 more |
| Westminster | 62,913 | 64 | 20 | Chlorine Dioxide, Disinfection Byproducts, Stage 2 DBP +2 more |
| Fort Meade | 62,234 | 1 | 1 | Disinfection Byproducts |
| California | 59,957 | 158 | 0 | |
| Annapolis | 43,780 | 10 | 2 | Disinfection Byproducts |
| Cumberland | 38,609 | 8 | 0 | |
| Aberdeen | 33,006 | 6 | 0 | |
| Salisbury | 31,338 | 52 | 10 | Disinfection Byproducts, Stage 2 DBP |
| Ocean City | 30,127 | 80 | 3 | Gross Alpha, Stage 2 DBP |
| Bowie | 25,000 | 3 | 1 | Stage 2 DBP |
| Berlin | 24,018 | 53 | 3 | Stage 2 DBP |
| Patuxent River | 22,000 | 40 | 0 | |
| Elkton | 18,405 | 141 | 23 | Disinfection Byproducts, Stage 2 DBP, Total Organic Carbon |
| Easton | 17,392 | 11 | 2 | Disinfection Byproducts |
| Cambridge | 15,690 | 16 | 3 | Disinfection Byproducts, Stage 2 DBP |
| Havre De Grace | 14,555 | 109 | 11 | Contaminant 2920, E. coli, TTHM |
| Prince Frederick | 13,580 | 62 | 0 | |
| Hopewell | 13,200 | 0 | 0 | |
| Stevensville | 13,008 | 42 | 1 | Disinfection Byproducts |
| Mount Airy | 10,294 | 25 | 2 | Disinfection Byproducts, Stage 2 DBP |
| North East | 9,610 | 57 | 26 | Contaminant 2920, Disinfection Byproducts, Stage 2 DBP +2 more |
| Lusby | 9,565 | 16 | 1 | Stage 2 DBP |
| Indian Head | 9,339 | 66 | 1 | Stage 2 DBP |
| Dunkirk | 9,200 | 8 | 0 | |
| Newark | 8,636 | 35 | 3 | Disinfection Byproducts, E. coli, Total Organic Carbon |
| Chestertown | 8,496 | 19 | 2 | Stage 2 DBP |
| Walkersville | 8,440 | 2 | 0 | |
| Brunswick | 7,312 | 6 | 1 | Disinfection Byproducts |
| Taneytown | 6,750 | 0 | 0 | |
| Hampstead | 6,600 | 1 | 0 | |
| Fruitland | 6,572 | 29 | 8 | Disinfection Byproducts, Stage 2 DBP |
| Oakland | 6,474 | 17 | 5 | Disinfection Byproducts, Fecal Coliform |
| Thurmont | 6,200 | 4 | 1 | Disinfection Byproducts |
| Poolesville | 6,005 | 10 | 0 | |
| Mountain Lake Park | 5,935 | 2 | 0 | |
| Lavale | 5,500 | 12 | 3 | Disinfection Byproducts, Fecal Coliform |
| Bel Air | 5,447 | 5 | 0 | |
| Leonardtown | 5,100 | 41 | 7 | E. coli, Stage 2 DBP |
| Lonaconing | 5,045 | 30 | 6 | E. coli, Stage 2 DBP, Total Haloacetic Acids (HAA5) |
| Delmar | 5,038 | 4 | 3 | Disinfection Byproducts |
| Chesapeake Beach | 5,000 | 3 | 0 | |
| Manchester | 4,954 | 3 | 0 | |
| Denton | 4,690 | 30 | 1 | Stage 2 DBP |
| Boonsboro | 4,565 | 24 | 1 | Stage 2 DBP |
| Perryville | 4,472 | 82 | 16 | Bromate, Stage 2 DBP, TTHM +1 more |
| Middletown | 4,363 | 18 | 6 | Disinfection Byproducts, E. coli |
| Emmitsburg | 4,300 | 17 | 2 | Disinfection Byproducts |
| Williamsport | 4,260 | 42 | 4 | Disinfection Byproducts, Fecal Coliform, Stage 2 DBP |
| Pocomoke City | 4,100 | 16 | 9 | Stage 2 DBP, TTHM |
| Princess Anne | 4,050 | 217 | 1 | TTHM |
| Willards | 3,791 | 10 | 1 | Stage 2 DBP |
| Smithsburg | 3,641 | 9 | 0 | |
| Waldorf | 3,332 | 160 | 6 | Chlorine, Chlorine Dioxide, Disinfection Byproducts +1 more |
| Centreville | 3,322 | 23 | 2 | E. coli |
| North Beach | 3,000 | 10 | 1 | Stage 2 DBP |
| Chrisfield | 2,976 | 3 | 0 | |
| Lothian | 2,884 | 39 | 1 | Stage 2 DBP |
| St Michaels | 2,650 | 16 | 8 | Barium |
| Federalsburg | 2,535 | 39 | 8 | Disinfection Byproducts, Selenium, Stage 2 DBP |
| Severn | 2,426 | 13 | 2 | Disinfection Byproducts, Stage 2 DBP |
| Snow Hill | 2,409 | 16 | 8 | TTHM |
| Westernport | 2,200 | 11 | 3 | E. coli |
| Hurlock | 2,150 | 5 | 1 | Stage 2 DBP |
| St. Leonard | 2,000 | 2 | 0 | |
| Perry Point | 2,000 | 16 | 8 | TTHM, Total Haloacetic Acids (HAA5) |
| Sykesville | 1,950 | 33 | 21 | Stage 2 DBP, TTHM, Total Haloacetic Acids (HAA5) |
| Hancock | 1,921 | 5 | 0 | |
| Greensboro | 1,905 | 58 | 1 | Stage 2 DBP |
| Ridgely | 1,900 | 31 | 2 | Disinfection Byproducts |
| Rock Hall | 1,750 | 5 | 0 | |
| New Windsor | 1,732 | 1 | 0 | |
| Myersville | 1,516 | 0 | 0 | |
| Pittsville | 1,500 | 8 | 1 | Disinfection Byproducts |
| Port Republic | 1,425 | 5 | 0 | |
| Timonium | 1,373 | 10 | 2 | Disinfection Byproducts |
| Funkstown | 1,300 | 1 | 0 | |
| Silver Spring | 1,248 | 0 | 0 | |
| Sherwood Forest | 1,200 | 0 | 0 | |
| Port Deposit | 1,187 | 230 | 6 | Disinfection Byproducts, Stage 2 DBP |
| Jessup | 1,070 | 17 | 1 | Stage 2 DBP |
| Hebron | 1,022 | 3 | 0 | |
| Union Bridge | 997 | 3 | 1 | Fecal Coliform |
| Farmington Hills | 990 | 9 | 0 | |
| Lexington Park | 892 | 15 | 1 | Stage 2 DBP |
| Grantsville | 885 | 4 | 0 | |
| Woodsboro | 846 | 22 | 0 | |
| Tysons | 828 | 1 | 0 | |
| Glen Arm | 818 | 55 | 9 | Disinfection Byproducts, Fecal Coliform, Stage 2 DBP |
| Oxford | 813 | 12 | 1 | Stage 2 DBP |
| Brandywine | 780 | 4 | 0 | |
| Preston | 750 | 19 | 2 | Stage 2 DBP |
| Queenstown | 705 | 29 | 0 | |
| St. Michaels | 675 | 1 | 0 | |
| Chesapeake City | 673 | 4 | 0 | |
| Ellicott City | 649 | 41 | 9 | Disinfection Byproducts, Selenium, Stage 2 DBP |
| Street | 643 | 89 | 1 | Stage 2 DBP |
| Millington | 625 | 11 | 0 | |
| Sharptown | 625 | 7 | 2 | E. coli, Stage 2 DBP |
| Leesport | 569 | 79 | 4 | Disinfection Byproducts, Stage 2 DBP |
| Grasonville | 556 | 10 | 2 | Stage 2 DBP |
| Secretary | 535 | 5 | 0 | |
| Huntingtown | 526 | 32 | 3 | Stage 2 DBP |
| Sudlersville | 497 | 5 | 0 | |
| Betterton | 481 | 16 | 6 | Disinfection Byproducts |
| East New Market | 480 | 9 | 0 | |
| Cecilton | 477 | 19 | 4 | Disinfection Byproducts |
| Vienna | 460 | 3 | 0 | |
| Reading | 430 | 43 | 1 | Stage 2 DBP |
| Tylerton | 409 | 188 | 5 | Stage 2 DBP |
| Newburg | 406 | 69 | 1 | Stage 2 DBP |
| Durham | 400 | 23 | 2 | E. coli |
| Seaford | 384 | 7 | 1 | Stage 2 DBP |
| Freeland | 336 | 17 | 4 | Disinfection Byproducts, Stage 2 DBP |
| New Castle | 325 | 13 | 4 | Disinfection Byproducts |
| Springfield | 320 | 2 | 1 | Stage 2 DBP |
| Crofton | 320 | 5 | 0 | |
| Midlothian | 300 | 5 | 1 | Stage 2 DBP |
| Lancaster | 300 | 19 | 2 | Stage 2 DBP |
| Accident | 300 | 4 | 0 | |
| Accokeek | 300 | 4 | 0 | |
| Rising Sun | 290 | 3 | 1 | Stage 2 DBP |
| Sacramento | 275 | 10 | 1 | Stage 2 DBP |
| Finksburg | 259 | 9 | 1 | Selenium |
| Alexandria | 256 | 0 | 0 | |
| Colora | 250 | 19 | 3 | Disinfection Byproducts |
| Potomac | 220 | 15 | 3 | Disinfection Byproducts |
| Belle Mead | 220 | 7 | 1 | Stage 2 DBP |
| Sharpsburg | 220 | 4 | 0 | |
| Linthicum Heights | 175 | 6 | 1 | Stage 2 DBP |
| Darlington | 173 | 20 | 3 | Stage 2 DBP |
| Reistertown | 170 | 4 | 2 | Disinfection Byproducts, Stage 2 DBP |
| Berwyn | 159 | 13 | 0 | |
| Marbury | 150 | 12 | 1 | Stage 2 DBP |
| Bishopville | 150 | 9 | 0 | |
| Mt. Savage | 130 | 33 | 2 | Gross Alpha, Stage 2 DBP |
| Herndon | 126 | 4 | 1 | Stage 2 DBP |
| Randalstown | 125 | 20 | 2 | Selenium |
| Hollywood | 120 | 13 | 0 | |
| Cascade | 100 | 4 | 1 | Stage 2 DBP |
Water Quality in Other States
Alabama 13,972 violations Alaska 73,527 violations Arizona 60,414 violations Arkansas 17,031 violations California 39,276 violations Colorado 42,596 violations Connecticut 28,800 violations Delaware 1,242 violations District of Columbia 115 violations Florida 36,335 violations Georgia 32,159 violations Hawaii 182 violations Idaho 26,078 violations Illinois 30,544 violations Indiana 18,261 violations Iowa 9,389 violations Kansas 19,480 violations Kentucky 9,427 violations Louisiana 32,039 violations Maine 6,830 violations Massachusetts 10,561 violations Michigan 15,820 violations Minnesota 3,784 violations Mississippi 25,296 violations Missouri 25,377 violations Montana 20,202 violations Nebraska 5,134 violations Nevada 8,167 violations New Hampshire 6,968 violations New Jersey 19,332 violations New Mexico 37,115 violations New York 93,834 violations North Carolina 54,399 violations North Dakota 8,431 violations Ohio 61,604 violations Oklahoma 128,472 violations Oregon 0 violations Pennsylvania 199,265 violations Rhode Island 0 violations South Carolina 13,045 violations South Dakota 19,565 violations Tennessee 20,607 violations Texas 263,180 violations Utah 71,655 violations Vermont 12,362 violations Virginia 15,298 violations Washington 54,459 violations West Virginia 81,622 violations Wisconsin 18,533 violations Wyoming 13,783 violations
Data Sources
Drinking water data from the EPA Safe Drinking Water Information System (SDWIS). Only active community water systems (CWS) serving 100+ people are included.