Date of Award

12-2009

Level of Access Assigned by Author

Campus-Only Thesis

Degree Name

Master of Science (MS)

Department

Civil Engineering

Advisor

Shaleen Jain

Second Committee Member

Jean MacRae

Third Committee Member

Willem Brutsaert

Abstract

Recent changes in streamflow for the New England region (based on 32 serially complete, unimpaired flow records) are reported and discussed from a sustainable resources management perspective. Place-based, use-inspired research questions about these changes are developed using a collaborative engagement research approach that tailors scientific information to planning and decision making needs. Specifically, the information needs of this project's end-users, the Maine Department of Environmental Protection and Maine Drinking Water Program, prompt this project's research questions. First, changing streamflow patterns are identified and discussed through the lens of Maine instream flow regulations and water user activities. Tests for trends in streamflow (mean, quantiles, and variance) at the monthly and seasonal level (analyses which match the time scales by which seasonal streamflow standards are set and applied, respectively) are performed. Trends in monthly and seasonal variance may be especially valuable metrics of change for users and regulators given their bearing on resource reliability. Analyses identifying changes at the daily level (improving the resolution of the timing of changes) are also employed. An example of how changes in flow can be translated into the changes in the risk of exceeding or falling below expectations or needs during windows of interest to water users is shown as well. These or similar use-inspired time spans and related questions are suggested as a starting point for inquiries into regional changes in streams. Changes in streamflow are also examined with respect to impacts on regional aquatic biology. Such inquiries respond to regulators' need to understand the impacts of changing climate on species' population dynamics and suit the spirit of state instream flow regulations, which intend to protect aquatic habitat. The ecologically-sensitive Indicators of Hydrologic Alteration (IHA; developed and tested by the ecological flows community over the past decade and a half) and several IHA-inspired indices are applied to the streamflow data sets to parse from the data set those changes in streamflow events with relevance for aquatic biology. The well-documented ties of the lifecycle of the endangered Maine Atlantic salmon to streamflow conditions are used as an example of how the IHA may be used to address specific, species-based questions about environmental stressors posed by climate-driven changes in streamflow conditions. Finally, contact is made with the principal water user group in Maine (municipal drinking water facilities), establishing dialogue on the presence, nature and manifestation of changing streamflow patterns on utility operations, including present and future concerns about meeting instream flow requirements. Their survey-based feedback permitted the construction of rudimentary facility-specific calendars identifying potential windows of vulnerability to operations. The survey process and resulting calendars appear to be a promising strategy for enhancing the lines of communication between water users, researchers, and state agencies about the affects of climate-driven changes in streamflow on water user activities. Overall, this research project seeks to provide answers to pressing regional questions about water resources management in New England and to suggest useful frameworks for answering those questions in a way that is meaningful for the broader water resources community.

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