Raspberry Shake’s Survival Story: Underwater and Still Shaking!

Uruguay is a country with a lot of water. What other countries call rivers due to their flow, in Uruguay are considered streams. The average annual rainfall is 1203.8 mm, although it can vary significantly due to the El Niño effect (excess rainfall) or La Niña effect (lack of rainfall). This effect (El Niño-Southern Oscillation – ENSO) has a great impact on livestock and agriculture, which account for 80% of the country’s exports. 

For seismic vault installations in the field, the risk of water damage to equipment is significant. Over the years we have improved our facilities to prevent water-related issues. However, economic and logistical constraints mean that we cannot always ensure fully waterproof installations, requiring us to accept certain risks in special cases.

Of all the seismograph makes and models we have deployed, only two have survived being totally submerged in water. In these cases, when opening the vault, we found only murky brown water and had to reach in blindly to retrieve the equipment. The only seismometers that survived were a well-known brand of broadband seismometers and Raspberry Shake in a watertight case.

This particular case involves station “Juan Saltorio Bufa”, located in Paso Mazangano, Cerro Largo, Uruguay, about 460 km (~six-hour drive) from Montevideo, the capital. The station is named after a dear friend and team member who passed away in a car accident while in service, some years ago.

The station had a solar panel, LTE router, controller, batteries, and a 12Vdc to 5.3Vdc downconverter to power the Raspberry Shake. The equipment was housed in a 40cm concrete vault, similar to one described in another blog, but specifically designed for Raspberry Shake. The vault is usually coated with cold polyurea to waterproof the interior and lid, and sealed with silicone or duct tape and polyurea.

We are uncertain about how the flooding happened. It’s possible that someone inspected the site, removed the cover, or left the vault lid slightly open. Alternatively, during the preceding dry season, the green grass around the vault may have attracted grazing animals, which could have bitten and torn off the plastic covering and silicone seal. Whatever the cause, once the rains arrived, water seeped through the unsealed gaps, completely flooding the vault.

Due to logistical and resource limitations, it took over five months before we could plan a field visit to investigate why the station was no longer transmitting data. In most cases, these issues are related to power or connectivity, often requiring a router or solar panel controller reset. 

However, when we arrived, we found the vault completely submerged (unfortunately, we forgot to take a photo at that moment). The only thing visible inside was brown water. We reached in, retrieved the equipment, drained and dried the vault, and examined the Raspberry Shake. Remarkably, the water had not entered the case.

Back in the lab, we opened the unit and confirmed it was internally dry and clean. After cleaning the connectors and exterior, we powered it on—and our Raspberry Shake was working again.

For our limited resources, losing this equipment would have been a major setback, so this was fantastic news. The sensor has now been tested in the lab for months and is ready for redeployment soon.

Given our experience, we can highly recommend Raspberry Shake for outdoor use, especially in environments where water exposure is a concern.