The riverine environment includes inland, coastal and delta areas characterized by limited land lines of communication and extensive inland waterways providing natural routes for surface transportation and communications. In this environment, waterways serve as primary lines of communication and frequently constitute key terrain. To control the key terrain naval forces must be able to control all three mediums. This control will be exerted through a combination of physical occupation, multi-spectral observation, and the ability to bring fires to bear. As in any other unique physical environment, Marines will encounter conditions having significant effect on tactics and equipment and must adapt to be successful.
Climate affects equipment and radio propagation characteristics.
Navigation over flat, featureless terrain or areas with limited observation will pose a challenge, especially during darkness, or when overhead cover attenuates the signals of position reporting equipment. Biological and medical factors associated with the riverine environment present serious health and safety concerns. Harmful insects, poisonous snakes, endemic diseases, and even harmful plants can restrict movement and have an adverse impact on unit readiness. In an environment where water is literally everywhere, the transport and delivery of potable water might well be critical to mission accomplishment. Naval forces will encounter a large noncombatant population in the riverine environment and can expect the enemy to be dispersed throughout it.