In addition to requiring some kind of water right, your diversion of water potentially requires a separate permit from the California Department of Fish and Wildlife (CDFW) known as a Lake/ Streambed Alteration (LSA) Agreement. These agreements are issued under Section 1602 of the Fish and Game Code, which authorizes CDFW to place conditions to protect fish and wildlife on any “substantial” diversion of any stream. Note that this includes many diversions from springs and wells.
Although an LSA Agreement is technically not a water right, it can be very similar to one in some ways. For example, it may contain terms limiting the season in which you are allowed to divert water, as well as the rate and quantity of diversion. One of the most common LSA terms is a forbearance period in which no diversion is allowed for several months during the late summer and early fall, when streamflow is naturally the lowest.
How do I know if I need an LSA Agreement for my diversion?
This can be tricky, because there are currently not any formal guidelines for what constitutes a “substantial” diversion. As a general rule, the larger a diversion is in relation to the amount of instream flow, the more likely it is to be substantial. For example, if you know your diversion takes more than 10% of the flow of the stream at its lowest level (during the late summer), you should assume it is substantial and an LSA Agreement is required. Practically speaking, this means that most residential diversions with an operational capacity of 10 gallons per minute that are located on tributaries throughout coastal California will be considered substantial. Smaller diversions can also be substantial – particularly when they take water from springs that provide crucial cold water flow to streams during the later part of the dry season. Larger diversions are very likely to be substantial, even where they are on larger mainstem rivers that normally flow year-round.
The surest way to determine whether you need an LSA Agreement for your diversion is to complete an LSAA notification form and send it to CDFW with the required fee. In cases where you are relatively certain your diversion is substantial based on the considerations above, or if your diversion is for any kind of commercial activity (including cannabis production), you would be well advised to do this. Some tips on filling out the form can be found here.
If you plan to store water for residential use, and therefore need to fill out a Small Domestic Use Registration, there’s a good chance you can avoid the time and expense of filling out the LSAA notification form. When the Water Board processes your completed registration form, it will send it to CDFW for the chance to review it and impose conditions to protect fish and wildlife. As part of this review, CDFW will usually determine whether it intends to require an LSA Agreement. In many cases, CDFW will conclude that no agreement is required, on the grounds that that the conditions it places on the SDU registration render the diversion “non-significant.” Thus, non-commercial homeowners should generally let the SDU registration process play out before filling out an LSAA notification.
If you will not be storing any water, and are unsure whether your diversion is significant, you can try consulting CDFW for advice. It may take a bit of persistence to find the appropriate local staff, but the effort is likely well spent.