Hello, this isn't exactly a pond question (although I have a pond and like this forum), it's a question about Water Hyacinth in an open waterway. The waterway specifically is a slough in my backyard that is part of the San Joaquin/Sacramento rivers Delta.

I ask this question because many people on this forum know a lot more about things than just ponds.

I am sensitive to the regulatory and environmental issues regarding the use of herbicides in open and public waters. But, I need help just figuring out what herbicides are even effective. I have done some research but some of this stuff is very expensive and the environmental stuff is sometimes difficult to determine.

I've seen references to the use of Glyphosate and 24-D. I've seen posts on this forum describing how different Glyphosates are more or less suitable to water applications.

I have seen an herbicide named Habitat, the description looks perfect for me but the stuff is expensive. To expensive to waste but I would use if effective.

So, I'll keep it short and just ask for comments and suggestions regarding this problem.

Beer, I would not consider spraying a chemical in CA on "public" waters...you might go to prison for life!

Have you called the local agency or Game warden to see if it can be controlled by them? If you are given permission to do anything, make sure it is in writing!

Heed Rainman's advice VERY closely. Far better for the governing agency to implement a management program on public water than an individual.
Beyond that, you might investigate Clearcast herbicide, which is in the same chemistry-family as Habitat but with much less "enviro-baggage" (aka "restrictions") - and is very active/effective on water hyacinth.