Fish and Game code Section 1602 requires any entity to notify CDFW before beginning any activity that may substantially divert or obstruct the natural flow of, or substantially change or use any material from the bed, channel, or bank of any river, stream, or lake. If CDFW determines that the activity may substantially adversely affect fish and wildlife resources, a Lake or Streambed Alteration Agreement will be prepared.

When is Notification of Lake or Streambed Alteration (LSA) required?

Fish and Game Code section 1602 requires an entity to notify CDFW prior to commencing any activity that may do one of the following:

• Substantially divert or obstruct the natural flow of any river, stream or lake;
• Substantially change or use any material from the bed, channel or bank of any river, stream, or lake; or
• Deposit debris, waste or other materials that could pass into any river, stream or lake.

Please note that "any river, stream or lake" includes those that are episodic (they are dry for periods of time) as well as those that are perennial (they flow year round). This includes ephemeral streams, desert washes, and watercourses with a subsurface flow. If may also apply to work undertaken within the flood plain of a body of water.

For more information, please contact the Department of Fish and Wildlife

LSA Website