I like Craig`s suggestion, but I think you need more than just a mailing list. You need to consider how to get your brochure into the hands of someone who can respond to it. If the water authorities are as bureaucratic as I think they might be, you risk having your brochure reach the mailbox of someone who has a secretary to process mail. And a lot of secretaries throw out things like brochures from companies they don`t know (or even from companies they do know).
A telephone "survey" might be a better way to go, if only because your survey can specify that you need to talk to the manager/executive responsible for water sourcing, or something like that. You can pitch your survey by offering to share a free report of overall survey results, and of course, you can mail your brochure along with that report -- to the person who you have already verified as the appropriate contact.
Having said that, I know the telephone survey has some pitfalls of its own. You`ll get refusals from many potential targets, for one.
It would not surprise me if this audience has several periodicals targeting it. Maybe you could invest some advertising dollars in that niche or find a conference and try to get yourself invited as a speaker.
In short, I think you might need multiple approaches for this.
I`m in the planning stage for some products that would be delivered via standard reports -- probably PDF documents available for download or distributed by email.
I think that a money-back guarantee would enhance my value proposition, but I`m not sure how I will ensure that I don`t give money back to customers who actually are just trying to get my product for free. For one product, I have an idea for a 30-day grace period, during which I could probably learn whether or not they actually "consumed" the material in my report. For other products, I`m not so sure.
What experience have you had with money-back guarantees?
If your experience was with intangible products like information, how do you guard against this potential problem?