Water Supply
As of 7/1/23
| Lowest safe level | -40′ (38% capacity) |
| Lowest historic level (3/5/67) | -34.3′ (45% capacity) |
| Highest historic level (6/1/84) | +1.8′ (103% capacity) |
| Number of years over spillway | 33 |
| Years of 110+% capacity | 31 |
| Daily safe yield (entire MDC system) | 300 million gallons |
| Communities served by system | 53 |
| Population Served | |
| 1946 | 1.5 million |
| 1963 | 2.1 million |
| 1990 | 2.2 million |
| 2020 | 3.1 million |
| MWRA Water System Demand | Million gallons/day (MGD) |
| 1985 | 333.9 MGD |
| 1990 | 285.1 MGD |
| 2000 | 251.7 MGD |
| 2010 | 204.3 MGD |
| 2020 | 195.7 MGD |
| 2023 | 190.6 MGD |