UW Aquatic & Fishery Sciences Quantitative Seminar

Gino Lucchetti

Senior Ecologist, Watershed and Ecological Assessment Team, Department of Natural Resources and Parks, King County

Assessing the efficacy of environmental protection measures in rural King County, Washington


King County, like all local governments, must balance land use and economic development with regulations and other actions, such as habitat acquisition and restoration, to provide environmental protection. For rural areas, the County’s environmental regulations rely on low density zoning, protection of critical areas and their buffers and best management practices for clearing, grading and stormwater runoff in order to avoid or minimize and mitigate the effects of development. Until recently, the County had never comprehensively assessed the adequacy of or compliance with its regulations. This presentation will summarize two recent studies assessing whether the County’s regulations are providing, or are likely to provide, the desired level (no adverse or detectable effect) of environmental protection.

For watersheds, the County’s Regulatory Effectiveness Monitoring project2 constructed a watershed-based framework to conduct a “natural experiment.” Land use permits and changes in land cover, hydrology (flashiness), water quality (conductivity, temperature), stream channel complexity (reach-averaged velocity), and biology (benthic invertebrates) were assessed for five years (2008-2012) in six “treatment” watersheds, with ongoing rural development, and three forested “control” watersheds with no development (nine watershed total in a BACI-type design). Unexpectedly low levels of land development, presumably due to the Great Recession of 2008, caused treatment levels to be low and probably not a rigorous test of the regulations. Therefore, to increase perspective, present-day land covers were compared to historic (~1910, 1936, 1948, and 1965), future full build-out and urban land cover scenarios. A hydrologic condition index (HCI) was developed to measure and compare differences in hydrologic condition (not just land covers) across scenarios. Although no environmental response was detected, the project’s low-levels of treatment stymied a strong test of the regulations. Still, the project’s comprehensive, detailed examination of land covers and regulations suggest relatively little future change in watershed hydrologic flashiness under low density zoning, particularly when compared to urban land use. It also suggested that noncompliance, while present, was not large and buffers may be being preferentially protected, as desired. An outstanding issue is the role of toxics on productivity of streams in low density, rural environments.

For floodplains, a comprehensive assessment of floodplain development and habitat protection and restoration actions was conducted in response to a finding by NOAA that FEMA’s National Flood Insurance Program (NFIP) was Jeopardy under the federal Endangered Species Act (ESA). As a result, the County’s mapped FEMA floodplains totaling some thirty-four thousand acres across six major watersheds were examined in detail to determine if the County’s current actions were protective of endangered species habitat and consistent with the ESA. For this, current and future potential land covers were compared by estimating the decrease in forest and increase in impervious land covers, i.e., the “bad” changes, projected to occur under potential full build-out and the concomitant change in those land covers that may result from protection of critical areas and regulatory buffers and habitat acquisition and restoration activities, i.e., the “good” changes. Additionally, potential development effects (good and bad) under County regulations were assessed for their effect on twenty habitat variables identified in NOAA’s Matrix of Pathways and Indicators. To be precautionary, as required under the ESA, the approach somewhat overstated the potential for bad and somewhat understated and the potential for good. The analysis concluded that when considering the combined net effect of good and bad changes there would likely be a net increase in floodplain forest cover with, at best, only minor amounts of new impervious and that the effect of regulations (zoning, buffers, clearing, grading and stormwater) should result in a variety of improvements and no adverse effects if implemented properly. As a result, the County’s floodplain land use was accepted as sufficient under the ESA. The analysis provides a framework for future assessments and the County has agreed to review and update findings at no less than five and no more than ten year intervals.

Together, the two studies provide the County with new information on how its regulations and other actions, such as habitat protection and restoration, are working. It also provides a framework and working hypotheses for future assessments as well as evidence to suggest that the County’s habitat protection and restoration actions may be facilitated and not be undone by development-drive change at the watershed or floodplain scales.

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