There is a temporary closure of Crater Lake until protocols are created to minimize the risk of contamination from invasive species which could potentially be introduced by divers. The temporary closure prohibits scuba diving and use of water gear in the lake.  The protocols being worked on will require divers to take specific precautionary measures prior to entering the lake.

Crater Lake has been increasing in popularity for scuba diving which also increases the potential for divers and their gear to carry microscopic organisms into the water.  The microscopic aquatic invasive microorganisms can cause a large amount of damage which is often irreversible.

Crater Lake is crystal clear and very pure, minor changes in the hydrologic environment of the lake could affect the purity and clarity of the lake permanently.  There is a large range of aquatic invaders from microscopic bacterial and viral pathogens to plants and animals which in their native environments are controlled by predators, parasites, pathogens, or competitors.   When these aquatic invaders are introduced into a pure environment such as Crater Lake, the natural checks are not present which provide the invasive species a big advantage over the native species.   These invasive species when introduced into a pure ecosystem such as the one within Crater Lake, are very expensive, difficult, and at times impossible to control. Examples of aquatic invasive species include: quagga mussels, spiny water flea, and viral hemorrhagic septicemia.  These can all cause very severe and permanent damage by decreasing the number of native species and changing the ecosystem.  These microorganisms are a major cause of extinctions.  The best way to reduce the risk of introducing invasive species into Crater Lake is to focus on preventing the introduction of these harmful invasives.