I was a lucky duck to intern every Friday this summer at HRWC. My role: continue work on HRWC’s Dam Removal Prioritization project. Back in 1995, the fisheries division of the DNR identified a few dams for removal (Argo, Peninsular Paper, and Dexter’s Mill Pond dam); but that was the only sort of prioritizing that had been done. When I told my Ann Arbor friends about the internship, they inquired: “So you’re doing something with Argo then?” My response: “Nope. It’s more of a watershed-wide initiative. HRWC is interested in creating a prioritization tool to score and rank the roughly 100 dams in the Huron River watershed to then develop a top list of high priority dams to look more closely at for potential removal.” My friends’ response: “Oh…”
Really, what it meant was that I got to delve into analyzing three Michigan dam removal prioritization case studies and three non-MI case studies to better understand the different approaches taken to assess, score, and rank dams. What I learned: dam prioritization is damn difficult.
Let me explain:
- there are a lot of lovely data from MDNR from which one could do basic dam rankings based on dam size, dam age, pond size, etc. Numbers. Nice neat numbers. But then,
- there are the more difficult aspects to attempt to quantify, such as cultural, community and historical value of a dam. And then,
- there are seemingly endless other scientific, economic, social, and environmental criteria by which one could decide to score and rank a dam.
Each case study represented a different approach to evaluating dams. Some prioritization reports were extensive and long. Some were quite short taking only a few criteria into account. And the criteria ranged from numbers and scientific categorization to general, best-guess, more subjective values.
And then there is the added complexity of how much each criterion should be weighted into the final scoring matrix – a subjective decision that could take any number of perspectives into account.
My favorite prioritization tool consisted of a laundry list of criteria that could be weighted in any number of ways, leading to infinite permutations of ranking outcomes – painting a nice picture of the reality of dam scoring and prioritization. There is no single, uniform way to go about it, because each watershed, community, local economy, and decision maker’s perspective is different.
But it sure makes for a damn good puzzle. And if you like puzzles like me, it makes for a “dam” good time.