Pivka jama – outflow sumps of the underground Pivka (Postojna system)

Behind Pivka jama, part of the Postojna cave system, the Pivka river flows on through a chain of outflow sumps towards Planinska jama. Divers first passed the 170 m long, 30 m deep first sump in 1975; in 2015 a sidemount team led by Igor Vrhovec and Sebastjan Gantar passed a fourth sump and surveyed 3.5 km of new river passage, and in 2017 they linked Pivka jama with Magdalena jama naturally through the extended Zvezni siphon (422 m, 17 m deep). Visibility is typically half a metre or less, and a large olm colony lives along the route.

Facts

Region: Slovenia – Lakes, Rivers & Caves
Area: Notranjska & Brkini (Cerknica, Postojna, Pivka)
Depth: 0–30 m
Level: advanced
Current: moderate
Type: cave
Coordinates: 45.8046137, 14.204598 (approximate)
Highlights: first outflow sump 170 m long, up to 30 m deep (passed 1975), series of five+ sumps towards Planinska jama, 4th sump 30 m long, 6 m deep (2015), 3.5 km of new passage surveyed in 2015, Zvezni siphon 422 m long, 17 m deep (2017), visibility often 0.5 m or less, 3 m counted as excellent, large olm (proteus) colony along the river, sidemount configuration used
Permit: Show-cave system operated by Postojnska jama d.d.; under ZVPJ Art. 14 the operator/concessionaire must be notified before entry. Under the Cave Protection Act (ZVPJ) every cave, including water-filled ones, is state-owned and protected. Only persons certified for independent caving (certificate checked by the Speleological Association of Slovenia, JZS) may explore caves, and they must notify the cave's custodian, concessionaire or protected-area manager in advance (Art. 14); closed caves can be entered only for scientific/archaeological work with a permit from the ministry responsible for nature conservation (Art. 17). There is no visitor dive permit: in practice diving here happens only as a member of the caving/cave-diving team that runs the exploration.
Issuer / contact: Postojnska jama d.d.
- Phone: +38657000100
- Email: info@postojnska-jama.eu
- Website: https://www.postojnska-jama.eu/
Tips: Research-only, not available to visiting divers: exploration is done by a small team of certified cave divers from Slovenian caving clubs with a 20–30-person support crew, supported by the show-cave company. Multiple sumps, near-zero visibility, cold water and long carries. Do not disturb the olms.

Pivka jama – outflow sumps of the underground Pivka (Postojna system)

Facts

Sources