Use and Enforcement: Utility Encroaching into Easement

My question involves real estate located in the State of: California

I have just moved into a property where one side has a 15' easement for public utilities. Next to one part of the easement is a pumping station owned by Cal Am Water utility. Recently they've been making changes to their pumping station as new homes are being built in the area, and as part of the change have encroached about 6' x 25' into the easement on the side of my property with part of a building and a barbed wire-topped fence (they extended their existing fence down the property line out into the easement).

Now I know they have a right to use the property because of the easement, but do they have a right to actually encroach and fence off part of the easement to include it into their pumping station? If not, what's my recourse?

Thanks

Use and Enforcement: Utility Encroaching into Easement