The pumping station is a location featured in Jak II. It is a large, tropical island north of Haven City, consisting mostly of large cliffs encrusted with artificial metal architecture and plumbing equipment. During Jak II, it was accessed via an air lock in the Water Slums, or by heading south of a neighboring island home to the landing pad. However, during Jak 3, following the renovation of the Water Slums into New Haven, the pumping station could not be accessed due to the air lock no longer being present. However, during Jak X: Combat Racing, the area was reconstructed and featured as a race track called the Atoll Arena.
At some point before Jak II, Baron Praxis shut off the water supply to the Slums in order to root out the Underground movement. Eventually, the Underground's leader Torn received information from his "friend in the Guard" that the valve to turn the water back on is located at the pumping station. After meeting Jak and Daxter and accepting them into the Underground, he sent them on a mission to turn it back on, stating that "if [Jak] survives, the Slums will be indebted to [him]." Jak succeeded in this, restoring water supply to the Slums.
Later, after meeting Krew and impressing him at the gun course, Jak was sent on a mission with Sig to hunt spyder gunners in order to collect them as trophies for the Hip Hog Heaven Saloon. Sig's weapon, a modified Peace Maker rifle, took a while to charge, requiring Jak to defend him from znorkle tooth ambushes while he charged it. After charging, Sig sniped each of them from a distance, afterwards noting that he would collect them and return them to Krew.
Torn lastly sent the duo on the mission "Find pumping station patrol" with the directive to find and protect an Underground ally who was possibly in trouble out in the station. After arriving at the patrol site, the two met Ashelin Praxis. Almost immediately, they were ambushed by more spyder gunners and juice goons which both Ashelin and Jak defeated. Ashelin relayed to Jak that the Baron, her father, is "up to something big" and "it may have something to do with the [Seal of Mar]." It is from her that Jak then received a Bazaar security pass.
The pumping station is located along the north wall of Haven City, accessed through an air lock in the Water Slums. It opens up directly to a small beach containing two small pumping apparatuses and a large tank reservoir. On both the east and west sides of the pumping station are a network metal scaffolding and platforms used for different purposes, as well as a few defenses. The metal platforms build up nearly to the very top of the main two cliffs and halfway up the eastern cliff. The lower levels of the pumping station consist mostly of sandbanks and water beds (mostly connected to the rest of the ocean), decorated with metal scaffolding leading to other places. Off the island's coast are a multitude of islets containing wind mills indicating energy production in addition to plumbing services. The pumping station has a variety of flora and fauna, with palm trees and grassy plateaus comprising most of the vegetation and znorkle tooths and glubs, as well as a variety of different metal heads, comprising the fauna. Perhaps more noticeably in regards to the flora, however, is the abundance of bush-like trees that scale the higher regions of the cliffs.
The island itself is divided into three smaller island areas, the first one of which is accessed directly after exiting the city. Each area becomes more easily accessible as each mission is completed. The first part, or southern section, is the largest of the three in terms of overall surface area, but is the shortest in terms of height, home to the smaller of the three cliffs. All of the island parts are connected in some way by a small network of metal platforms. The western section is noticeably smaller in square footage, but has more actual pumping equipment and appears to serve a more significant purpose. It is in this section that the valve found by Jak and Daxter is located. The northern section is the tallest, and most notably contains the area that Ashelin and a Seal of Mar embedded in a stump were found.
Notably there is a second island close-by which can only be reached by using the JET-Board and crossing an old pipe. Then following a shortcut through a small canyon will lead you to the dig site and the weapons factory. This shortcut is labeled on the map as the landing pad.