Ojamo mine pond (Ojamon kaivoslampi)
The flooded open pit at Ojamo, Lohja, from which divers enter the horizontal levels of the old limestone mine. Closed to outsiders; diving runs through the rights-holding club and two training providers.
The mine pond is the open pit of the former Ojamo lime mine. Its water reaches ground level, so divers can kit up beside the water and enter directly, then descend to the first tunnel level. Safety and rescue structures have been installed at the pond according to the national broadcaster.
The site is shared by recreational mine divers of the rights-holding association and by professional diver training run by the vocational consortium Luksia and the maritime safety school Meriturva.
The environment
Open-pit pond leading to cold (about 4 °C), clear mine levels with horizontal tunnels at fairly constant depths; summer surface water can be murky.
Conditions
Surface water warms in summer (around 20 °C) and loses clarity; deep water stays about 4 °C (2013 figures).
Typical ranges from published sources, not current conditions.
Every fact on this page, with its source (5)
| Fact | Status | Source |
|---|---|---|
| Access for outsiders to the Ojamo mine pond is prohibited; the rights holders are Ojamon kaivossukeltajat ry (since 2024), Luksia and Meriturva. | Reported | [1] |
| The most common dive depths are 28, 38 and 58 m. | Reported | [1] |
| Deep water is about 4 °C year-round and surface water reaches about 20 °C in summer.2013 source. | May be out of date | [2] |
| Diving under ice requires cave or mine diving training. | Reported | [1] |
| The water is level with the ground, so divers can park beside the pond and enter directly.2013 description. | May be out of date | [2] |
Verified: stated by an official or primary source we opened. Reported: from a secondary source only. Sources conflict: the note gives both versions. May be out of date: the newest source we found is old.
Written in our own words from the sources above. Report a correction