Montgomery County Reservoir

An abandoned water treatment station home to half a dozen raiders and, depending on your level, a Sentry Bot. There are ammunition boxes in the upstairs of the barn and in a corrugated metal shed to the northwest.

Description
The treatment station serves no real use other than a stopping point in the Mid North West part of the map, as it is not a place of random encounters, nor is there any extraordinary loot inside the reservoir excluding the 30 HP health boost (with only 2 Rads). This can be used by activating the wheel on two of the four circular water tanks. There is also an abandoned barn to the northwest where three ammunition boxes (1 very easy locked) can be found on the second floor. West of the barn are three more unlocked ammunition boxes in a makeshift shelter.

Trivia
The Montgomery County Reservoir is a real landmark in Montgomery County Maryland, but its location on the Fallout 3 map places it in Northern Virginia.