Reservoir Watches are inspired by good ol’ utilitarian manometers, gauges, counters and other measuring instruments for the simple reason that they are precise, easy-to-read instruments and just the kind of tool you might need on your next adventure. The Reservoir Hydrosphere is a dive watch with a unique personality that looks nothing like the usual suspects spawned by the Submariner floating on the market. Inspired by submersible pressure gauges, the latest Hydrosphere is cased in bronze and has a green dial inspired by the colour of cenotes (sinkholes) dotting the Yucatan peninsula.
Spanning the classic division of action watches – automobiles, aviation and marine – French brand Reservoir (French for fuel tank) offers a refreshing take on sports watches that borrow heavily from the world of instruments. From jerry cans to manometers, the brand’s single-hand watches all feature similar layouts: the retrograde minutes span across an arc of 240° like RPM counters, the jumping hours appear in a window at 6 o’clock, and the power reserve is displayed like a fuel gauge at the bottom of the dial.
The Hydrosphere joined the line-up of aviation and automobile-themed watches in 2019 and takes its design cues from a submersible pressure gauge, a crucial piece of diving equipment that lets you know how much air remains in your tank. Don’t miss our contributor and resident diver Derek Haager’s report on his underwater adventure with the Hydrosphere.
Sharing the same specifications as other Hydrosphere models, this watch’s 45mm diameter and 15mm thick dimensions firmly plant it as a solid, robust tool watch. The case is crafted in bronze (except for the caseback, which is steel) to underscore its maritime connections and displays a sporty matte finish. The wide notches on the bronze unidirectional bezel aid grip, and the bezel has a black ceramic insert with a double luminescent scale for reading the time at different diving depths. Naturally, the crown with its rubber tread is screwed-down to ensure the 250m water-resistance, and there is a helium valve at 9 o’clock that does not protrude.
The fact that the Reservoir Hydrosphere has no lugs allows it to sit well on the wrist, even smaller wrists. However, there is no denying that this diver has a lot of wrist presence.
Cenotes are natural sinkholes formed by collapsed limestone bedrock that expose groundwater from the filtration of rain and underground rivers. Dotted around the Yucatan peninsula, cenotes provided drinking water for the Maya. They were also considered sacred portals to the underworld and used to deposit precious offerings, including human remains, as a form of ritual sacrifice. The water in cenotes is a vivid emerald green, a colour that has been replicated on the dial of the watch, complete with a sunburst pattern. Fitted with the signature single hand for the retrograde minutes, the Hydrosphere features a spinning disc on the axis of the central hand that serves as a running indicator.
Using a similar layout to a submersible pressure gauge, three bands of colour are represented on the peripheral minute track (blue, beige and red) with its applied, fully lumed double digits at 10-second intervals (00-60). The jumping hours in the circular aperture are covered with a magnifying lens, and the power reserve appears in the curved bar at 6 o’clock with a white dot travelling from blue to red.
New, improved movement
The movement used inside former Hydrospheres (ETA 2824-2 with a 124-part module) has been upgraded in this latest edition. Fitted with the new Reservoir RSV-240, the movement mounts the 113-part proprietary module for the retrograde minutes, jumping hours and power reserve on top of a La Joux-Perret G100 base. With a frequency of 28,800vph, the movement ups the power reserve from 37h of former editions to a beefier 56 hours.
Availability & Price
The Reservoir Hydrosphere Cenote comes on a matching green NATO strap with bronze stays and an additional black rubber strap in the box. Although the model is currently Sold Out on the brand’s webpage, it will be available to order again in December 2022 for EUR 4,850.
For more information, please visit reservoir-watch.com.