Sector G Hydro Electric

"If you're waiting for the train to Sector G, then you'll probably better off walking it. I overheard someone say that all the trams on this end of the facility are having problems."

- Black Mesa scientist

Sector G Hydro Electric is one of the seven main sectors of the Black Mesa Research Facility, providing the power for the facility. It is connected to the Red Line of the Black Mesa Transit System.

Topside Hydro Plant
Sector G's most prominent feature is the Topside Hydro Plant, featuring the iconic Hydro-Electric Dam. A road passes above the dam; one direction leads to the Advanced Biological Research Lab, the other to a series of partially destroyed freight hangars. There Black Ops and Race X creatures squabble over the area.

When Gordon Freeman reaches the dam from the Advanced Biological Research Lab, it is mostly intact, but the HECU posted a cannon on the other side. An Apache is also patrolling the area and destroys the bridge linking the intake tower to the dam. Freeman is forced to quickly dive in the basin where an Ichthyosaur is swimming to reach the intake tower and stop one of the propellers below, then pass under the dam to proceed further.

Later Adrian Shephard reaches the dam from the hangar area located on the other side. There he witnesses his comrades assaulting a trapped Gargantua, while the G-Man is talking on a cell phone in the intake tower, before leaving through a portal where Sprites are diving in. He then defeats the creature with dynamite, damaging the middle of the dam. At that point, the other side of the dam from which Freeman originally comes is blocked by Race X moss, and the water level on the other side of the dam has also greatly risen.

A duct system inside the dam leads to exit H-287GQ, located in a small desert area. Farther Sector E Materials Transport can be reached through an Ordinance Storage Facility, under which the Gene Worm appears.

Drainage Canal
Located at level 5, and accessed by Barney Calhoun through Entry Point B-03, the Drainage Canal is used for Waste Crushing and Disposal. It features a large lift used to move important items such as crates, and two large wheels in the canal itself used to crush garbage. The Drainage Canal is also connected through a small trapdoor to a small road linking the Freight Yard to the South Exit.

That area of Sector G is reached from the Black Mesa Transit System by the Sector G Main Access Lift, giving access to all five levels of that sector, and being adjacent to another lift. A Small Materials Storage Area full of cardboard crates and a crane system in a bigger storage area can also be found at level 5. It is unknown how the Drainage Canal area connects to the Topside Hydro Plant.

Behind the scenes
The name "Topside Hydro Plant" is given in a Black Mesa Announcement System announcement; the name "Hydro Electric" is given in a Black Mesa Transit System map seen in Blue Shift. It is not clearly stated that the Hydro-Electric Dam is part of the Topside Hydro Plant and that it is located in Sector G, but given the Sector's name, that seems logical.

Trivia

 * The Hydro-Electric Dam is very similar to the Hoover Dam.

List of appearances

 * Half-Life
 * Half-Life: Opposing Force
 * Half-Life: Blue Shift