Water is the second episode of the TV series, Battlestar Galactica, and aired during the show's first season.
- "When a mysterious explosion destroys most of the Galactica's water supply, Adama and President Roslin attempt to control the ensuing riots, while Baltar searches for any Cylons who may have infiltrated the crew."
- —Battlestar Galactica: The Complete Series DVD case.
This episode starts out on Galactica with Lieutenant Sharon "Boomer" Valerii sitting in a store room, wearing her flight suit and completely soaked with water. Motionless at first, she comes too and realises what is going on. She finds a duffel back with a spare uniform with her name on it. Quickly changing she finds G-4 explosives, marked with detonator #A-7, in the same pack and quickly disassembles it. After changing, Lt. Valerii enters the D2 Repair Bay hoping to return the detonator to the small arms locker. She is spotted by Specialist Cally Henderson, who notes her unusually early arrival at 0545, but she brushes it off. Finding the right case in the locker, Lt. Valerii finds that detonators #A-1 through #A-6 are also missing. Elsewhere on the ship, they remotely arm themselves, but their location is so far a mystery.
Lt. Felix Gaeta alerts the crew of Galactica to the arrival of Colonial One on Galactica's hangar deck. Col. Saul Tigh is in his dress uniform ready to greet President Laura Roslin, but is more concerned about drawing on his liquor bottles to ration out his alcohol. CAG Cpt. Leland Adama gets ready for the event, and his haunted by the recent destruction of Olympic Carrier, which Commander William Adama advises to put behind him. As Colonial One docks, President Roslin is briefed as to the boarding ceremony, though she admits to Billy Keikeya that she dislikes the protocol, only going through with it in the hopes of pleasing Commander Adama. Commander Adama, ironically, only insisted on this in the hopes that making her feel Presidential would ease tensions between the two. During her official tour of the ship, President Roslin is shown a standard procedure for refilling neighbouring ships with water; Galactica's water reclamation is at close to 100% efficiency, meaning it can go years without new water supplies, but civilian ships do not have such efficient equipment.
Meanwhile, Lt. Valerii meets with Chief Galen Tyrol in private, where she informs him about the missing detonators. Chief Tyrol is initially angry at her for failing to report this to the Master-at-Arms, but she explains that because of the recent rumours of Cylons with human form infiltrating the fleet she will be the obvious suspect. While they discuss what to do, the bombs detonate and release water out into space. Chief Tyrol leads a damage control team including Specialist Henderson into the water tank, while Raptor 478 observes from outside, crewed by Lt. Valerii and Lt. Alex Quartararo. Specialist Henderson spots fragments of the detonator, with a pink powder residue on them. Chief Tyrol is reluctant to rule them as bomb components, however.
Meanwhile, President Roslin; Lt. Gaeta and Dr. Gaius Baltar are invited to a briefing on the situation. Lt. Gaeta has determined some 10 million "JPs" of water was lost in the explosion, which amounts to 60% of the water Galactica was able to supply to the fleet. Commander Adama orders a ban on laundry and showers on the ship for the time being. The available drinking water will run out on Galactica even if transferring to other ships is not taken into account. As one third of the fleet was already short and water to begin with, approximately 16,000 people are expected to be affected by water shortage in two days. President Roslin has Keikeya alert the captains of those ships to ration their water as well to stretch it out. President Roslin inquires as to what caused the accident, which Lt. Gaeta theorises was the result of structural failings in the ship brought on by the nuclear blast it suffered during the Fall of the Twelve Colonies. Commander Adama makes an order for astronomy teams to locate nearby star systems with planets with water, and Col. Tigh comes back with five such star systems with planets suspected of carrying water. The Raptor teams to be sent out to find this water must locate a large enough source, as well, as Dr. Baltar determines the entire fleet would require a minimum of 82 tons of grain; 85 of meat; 423 of fruit and vegetables, and 2.4 million JPs of water per week.
Chief Tyrol is ordered to submit his findings at the briefing. To cover for himself and Lt. Valerii, he reports on his suspicions of the being a G-4 "type" detonator involved. When this normally would have meant the Master-at-Arms receiving orders to investigate, Chief Tyrol adds that he already talked to her, and she has independently confirmed them to be G-4 and that several of Galactica's detonators are missing. Hoping to stall an investigation, he adds that due to spotty record keeping and lax security since the attack, they may never know who took the detonators, but warns that one of the detonators was not accounted for in the water tank, meaning it may still be a risk. Commander Adama is satisfied, and ends the briefing, with everyone advised it is strictly confidential. Left with only Col. Tigh; President Roslin and Dr. Baltar in the room, Commander Adama makes it clear it is obvious a Cylon agent was involved, and puts Dr. Baltar on the spot about the slow progress of his Cylon Detector, assigning Lt. Gaeta to his staff to ensure the completion of the machine.
Lt. Valerii reports on deck, where she is pleaded by Cpt. Adama to find water in her trip, as the news of water rationing has already led to fights taking place in the fleet. Ready to take off, she is told by Chief Tyrol that he has saved her back, but she is worried he suspects her involvement.
Elsewhere, President Roslin follows Commander Adama to his room to discuss the riots in private, where they bond over an exchange of books. Having only brought A Murder on Picon with her on her first trip to Galactica, she is handed a copy to keep of Edward Prima's Dark Day, a literary classic the two appreciate, but which Roslin has not yet read. Turning to the real issue, Commander Adama refuses the request to send Marines over to the civilian ships, as there is a serious risk the Marines will kill civilians if caught up in fighting.
Lt. Gaeta accompanies Dr. Baltar to discuss the computer development, but Dr. Baltar is distracted by the pilots' lounge, where Lt. Kara Thrace is holding a card game. He shows himself an expert card player and bests Lt. Thrace, who he flirts with throughout. Ready to leave with his winnings, he lights a fumarello-derived cigar as a gift for Lt. Thrace.
During the water search, Lts. Valerii and Quartararo become the only crews left out there after the other crews report the first four star systems did not have water as hoped. Lt. Quartararo names the area "Kimiko" in name of a woman he knew. It is quickly determined to hold water, but Lt. Valerii refuses to acknowledge it, and prepares to detonate the ship with the final G-4 which was smuggled on board. She comes too again, and announces the discovery of water. When they return to Galactica, Lt. Valerii realises G-4 is there, showing she has no memory of what she does in her blackouts.
Back on Caprica, Lt. Agathon and the Number Eight bond over rationed food. He isn't sure why she would take a Raptor back to rescue him, knowing it would have meant disobeying orders. She explains she regretted leaving him behind to change the subject. While they
On the deck, the Raptor crew returns to a celebration. Taken away to take part, Lt. Valerii casually warns Chief Tyrol about the problem. Soon after, Chief Tyrol meets with Lt. Valerii, where he tells her he handed the G-4 in to the Master-at-Arms and lied about having found it during routine maintenance.
On Caprica One, President Roslin personally congratulates Cpt. Adama for the mission. Hearing he has problems over the Olympic Carrier incident, she tells him that President Richard Adar kept a list of all fifteen victims of a massacre caused by his decision to send Marines to a protest on Aerilon, and that for Cpt. Adama he will never know if his actions were a mistake. She hires him for the position of Military Adviser, but insists she needs him to give advice on military procedure, avoiding any problems with his father.
The script for "Water" was longer than needed for a 42-minute episode, leading to 10–12 minutes of extra scenes, sequel to an entire act, being cut.