Prioritizing Streams for Protection and Restoration: Does a Triage Approach Make Sense?

Although Maryland is a small state (9,774 square miles), it has a dense drainage network of at least 10,000 miles of perennial streams and rivers.  The human population in 2010 was 5,773,552 (increase of 9.0% since 2000), which makes Maryland the seventh most densely populated state in the U.S. (595 people per square mile).  Urbanization and other land use changes are major stressors on the State's waters.  Between 2000 and 2009, the Maryland Department of Natural Resources conducted a probability-based monitoring program that assessed the condition of non-tidal, 1st through 4th order stream sites based on multi-metric biological and physical habitat indicator scores.  These assessments at 1,370 randomly-selected sites were extrapolated to all streams in the State.  Protecting healthy streams and restoring degraded streams are goals of local, state, and federal agencies in Maryland.  But with so many miles of streams to deal with and agency budgets stretched to the limit, there are far more miles of streams to be restored than there are available dollars to restore them.  A prioritization scheme is needed to decide where and how limited dollars should be spent to achieve maximum benefit.  This situation is analogous to a hospital emergency room, a battlefield, or the site of a natural disaster----places where the number of injured or wounded people exceeds the available medical staff and/or supplies needed to treat them all in a timely manner.  To decide the priority of patients' treatments based on the severity of their injuries and their chances of recovery, a sorting process called triage is performed.  We used a triage approach to sort streams into four treatment priorities, with condition categories and color codes, that can be used to guide management actions:  Priority 1, red--moderately degraded, restore first and soon to maximize recovery potential (2,390-2.574 stream miles); Priority 2, yellow--slightly degraded, minimize stressors, postpone treament or let the stream heal itself, then protect (3,310-3,770 miles); Priority 3, green--mostly healthy, comparable to reference conditions, protect (1,655-1,839 miles); and Priority 4, blue--severely degraded, eliminate human health hazards, do not restore (919-1,471 miles).  This triage approach is the first step in targeting stream restoration efforts.  Priority 1 streams should be sorted again by stressor types and sources to plan specific management actions.