Environmental Engineering PhD?

<p>I had always planned to get my master's degree at some point in my life, but was forced to do it sooner than later because of the terrible state of the economy. I applied for every job in my field within an hour and a half commute from my apartment after I received my BS, and never received one job offer despite solid grades and an EIT certification. Fortunately, I've been given a research assistantship and the opportunity to complete a 4-5 year project and receive a PhD. Alternatively, I could stop at my master's, but I'm not exactly sure which path to pursue. I know that this question has been asked before for those in mechanical or aerospace engineering, but I believe the answer may be different since I'm an environmental engineer.</p>

<p>On the one hand, I enjoy doing actual engineering design (like choosing a type of wastewater treatment plant, making the plans for it, and seeing it realized), which I could simply do with a master's degree. I was involved in such a project my last year as an undergraduate, and had a great time designing the plant from the ground up. I could see myself opening a branch of the company that hires me some day, and would be very satisfied with that kind of life. I heard that PhD's aren't usually hired for this kind of work, and are actually at a disadvantage because they start at a higher (and therefore undesirable) pay range. They're overqualified, so to speak. </p>

<p>On the other hand, I like the idea of being an instrument of progress. I want to move knowledge forward, even if it's only by a small amount. However, I'm worried that I'll be restricted to only a few government agencies like the EPA, and fewer labs that exist than companies that do engineering design. Is it true that there is less opportunity for a researcher than there is for a professional with a master's degree in this field? It would also be nice to teach at a university some day.</p>

<p>I'm basically looking for information that would help me weigh out these choices. If you could tell me the pros and cons of each, specifically in environmental engineering if possible, I would be very grateful.</p>