SUPPORTING FISH-FRIENDLY LAND USE DECISION MAKING Kitsap County s Use of Alternative Futures Planning in the Barker Creek Watershed

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1 SUPPORTING FISH-FRIENDLY LAND USE DECISION MAKING Kitsap County s Use of Alternative Futures Planning in the Barker Creek Watershed Keith Folkerts 1, Hal Beecher 2, Brian Skahill 3, Terra Hegy 2, Robert L. Vadas, Jr 2, Steve Boessow 2, Paul Nelson 1 ABSTRACT Throughout the Puget Sound land and water resource managers plan for salmon recovery and habitat protection by addressing future urbanization and groundwater withdrawals. Often planning and development result in direct impacts to sensitive salmon streams. The time-lag between decision making and the impact to the resource can be decades; the impacts are often incremental and appear insignificant. In Kitsap County these temporal and spatial land use and environmental planning challenges are being successfully bridged using alternative futures planning process which simulates and assesses future watershed conditions under various land and water use scenarios. This paper presents how policymakers utilized the alternative futures planning process to assess and make important land use and population growth decisions while protecting and conserving salmon and water resources. Kitsap County elected officials envision Kitsap as a place where Education, land use planning and coordinated efforts assure that the forests, clean air and water that Kitsap is known for are sustained for the benefit of current and future generations. (Kitsap County, 2005) In trying to accomplish this vision, local land use decision-makers face numerous daunting challenges. Several of these challenges have been successfully addressed by an alternative futures planning process, resulting in the adoption of a land use plan for the Barker Creek watershed that was designed to maximize the watershed s properly functioning conditions. BACKGROUND The Challenges The first challenge land use decision makers face when trying to be fish-friendly is a temporal mismatch: There is a long time lag between making a decision about zoning and seeing the results of that decision. A decision to keep an area in low density rural zoning may cause immediate harm to development interests today, but the resulting benefits of that decision to the watershed s aquatic resources may not be attained for decades. The second challenge is a spatial mismatch: A typical landowner s perspective will include his or her parcel and perhaps neighborhood, but rarely does it include his or her watershed. When a watershed view is presented, landowners typically think the development of their single lot has a negligible impact on the health of the watershed. However, it is well documented that within a watershed seemingly negligible impacts can add up to large changes. 1 Kitsap County, Department of Community Development Natural Resources Section 2 Washington Department of Fish and Wildlife, Habitat Science Division, Water Resources Section 3 US Army Corps of Engineers, Engineer Research and Development Center, Watershed Systems Group

2 A third set of challenges can be described as institutional mismatches: Resource agencies lack land use authority and land use agencies lack resource expertise. The insights learned through scientific efforts can be highly technical and inaccessible to the public and their elected decision makers. Because of the way our economic system has evolved, many of the costs are monetized and readily understood, while many of the benefits are non-monetized, are not readily apparent, and/or lack simple explanation. Planning has evolved in a way that leaves many water issues to be considered only in largely after-the-fact analysis instead of in the actual planning stages. Another challenge, identified in the County s previous round of alternative futures planning, is that the alternative futures effort should be fully integrated into the County s growth management planning efforts. The alternative futures process is meant to be a decision support tool ; as such it must be sufficiently flexible to work within the existing decision making environment. For land use planning in Washington, that means being able to work within a highly regulated process with requirements for public involvement, timeliness, and use of scientifically valid analyses. With these challenges in mind, County staff synthesized the following problem statement: County land use decision makers lack the technical basis and public support to implement a land use plan for the Barker Creek watershed which protects and preserves its beneficial uses and promotes properly functioning watershed conditions. The Solution With funding support from a Centennial Clean Water Fund grant (G ) administered through the Washington Department of Ecology, Kitsap County and partnering agencies addressed this problem by embarking upon the Barker Creek Alternative Futures planning process in support of a 10-year all-inclusive update of the County s Comprehensive Land Use Plan. The alternative futures effort addressed the temporal and spatial mismatch challenges by providing the public and decision makers with a sense of how their decisions today will impact land, streams and salmon decades from now. It also helped bridge institutional gaps by providing resource agencies with a meaningful way to contribute to land use decision making, while allowing land use authorities to benefit from sophisticated natural resource analysis in a readilyunderstandable and highly pertinent format. The alternative futures process brought the discussion of water and aquatic resources to an equal footing with such issues as transportation and capital facilities planning through the structured growth management planning process. The Setting Kitsap County is located in the Puget Sound lowlands surrounded by the main basin of Puget Sound to the east and Hood Canal to the west. Situated west of Seattle and north of Tacoma, Kitsap County is the third most densely populated county in Washington. Barker Creek watershed drains to Puget Sound s Dyes Inlet and is home to chum and coho salmon, and steelhead and cutthroat trout. About one half of this watershed is within the Silverdale Urban Growth Area; land use planning for Silverdale, an unincorporated area, is the responsibility of Kitsap County. Barker Creek is a relatively urbanized watershed by local standards: the watershed covers 1.0% (4.0 square miles) of the County s landmass, but in 2000 contained an estimated 2.6% (6,010) of the 2

3 County s population. The watershed s total impervious area is estimated at 20.5% and forest cover at 63.0% (Kitsap County DCD, 2002). ALTERNATIVE FUTURES LAND USE PLANNING Technical Analysis Tools Three types of modeling were used to support this planning project. A County planning department analyst used a geographic information system (GIS, ArcGIS 8.3) to model future land use scenarios; a Corps of Engineers research scientist used Hydrological Simulation Program- FORTRAN (HSPF) to model stream flows; and a team of scientists with Washington Department of Fish and Wildlife used Riverine Habitat Simulation Software (RHABSIM, Thomas R. Payne and Associates) to model salmon habitat quantity. Land Use Advisory Groups Several citizen-based groups were involved with the shaping of the alternative land use scenarios and selection of a preferred alternative. A group of citizens and stakeholders, primarily from Barker Creek and other nearby watershed, participated in the Northern Dyes Inlet Watershed Academy a series of six meetings to discuss important planning and water-related scientific issues. The County s Natural Resources staff organized these meetings to provide an opportunity for technical experts to interface with members of the public. The graduates of this series were invited to participate in the Silverdale Citizen s Advisory Committee s watersheds subcommittee. The Silverdale Citizen s Advisory Committee was charged with creating a detailed subarea plan for the Silverdale area (which includes Barker Creek watershed). This two-year planning process was organized by the County s Community Planning staff and dealt with issues ranging from aquatic resources to zoning; from building design standards to transportation. Their resulting subarea plan was submitted to the Planning Commission as the Silverdale Committee s preference for how the countywide Comprehensive Plan should be revised. The Planning Commission, an advisory group required by state growth management regulations, advised the County s Department of Community Development and Board of Commissioners throughout a year long effort to update the countywide Comprehensive Plan. The final Comprehensive Plan Update, dealing with issues such as land use, natural systems, economic development, housing and transportation, was adopted by the Board of Commissioners in December Alternative Futures Modeling The Alternative Futures planning process employed by Kitsap County was a mix of technical analysis and community-based planning. Land Use modeling: County staff and the Watershed Subcommittee members identified realistic future alternative land uses within the Barker Creek watershed under an Expansive scenario, a Conservative scenario, and a Plan Trend scenario. The County s GIS analyst used parcelscale average levels of imperviousness and forest cover to create a virtual build out of the watershed under each scenario. The changes for the watershed under each plausible scenario were relatively modest. See Figure 1. 3

4 Dye s Urban Low: 5-9 DU/Ac Silver-dale Rural: 1 DU/5 Ac Central Kitsap Dye s Urban Low: 5-9 DU/Ac Silverdale Urban Restricted: 1-5 DU/Ac Central Kitsap Dye s Urban Low: 5-9 DU/Ac Silver-dale Rural: 1 DU/5 Ac Central Kitsap Current/ Plan Trend Expansive Conservative Figure 0: Land Use Scenarios analyzed: Current zoning ( Plan Trend ), Expansive, and Conservative Stream flow modeling: Taking advantage of on-gong federal efforts to model local watersheds using HSPF, the County hired the Corps of Engineers modeler to create, calibrate and validate an HSPF model of the Barker Creek watershed. The model took into account existing levels of imperviousness and forest cover, among other things, to explain through hydrographs how Barker Creek responds to precipitation. Using the GIS-generated land cover layers, each future scenario was used as an input for the HSPF stream flow model. Also modeled was the Historic conditions scenario, which assumed no imperviousness and total forest cover. The results were largely as expected: More urbanized scenarios showed more frequent and higher peak flows. See Figure 2. The modeled change from historic Figure 0: Hydrograph of Current vs Modeled Historic Conditions conditions to current conditions was much more pronounced than the subtle differences among the modeled future scenarios. 4

5 Salmon Habitat Quantity modeling: WDFW s Habitat Science Division s Water Team selected two sites on Barker Creek to conduct detailed assessments of salmon habitat quantity at differing flows. The RHABSIM model uses existing channel conditions and considers depth, velocity, and substrate material to determine the quantity of suitable habitat (WDFW, 2006). See Figure 3. In keeping with local expectations, more stream flow means more salmon habitat (with the exception of cutthroat spawning), W U A Chum Spawning Coho Spawning Steelhead Spawning Cutthroat Spawning By using the modeled stream flows as the input, it was 500 possible to compare how much 0 salmon habitat each scenario provided. A Mitigation Streamflow (cfs) scenario was also modeled; in this scenario 2 cfs of stream flow was added to the Figure 0: Salmon Habitat Modeling: Weighted Usable Area vs Stream Flow Conservative scenario during low flow periods to assess modeled impacts of increasing low flows through such actions as enhanced stormwater recharge or streamflow augmentation with reclaimed water. See Figure 4. As with the land use and stream flow modeling, the differences among the various future scenarios were subtle. The change due to the stream flow augmentation during low flow periods Quantity of Habitat Available by Scenario & Life Stage, Lower Barker Site, Change from Current Conditions 160% 150% 140% 130% 120% 110% 100% Historic Plan Trend Alternative 2 Alternative 3 Mitigated 90% 80% 70% 60% Chum Spawn Coho Spawn Cutthroat Spawn Steelhead Spawn Coho Rearing Cutthroat Rearing Steelhead Rearing Rainbow Trout Winter Figure 0: Salmon Habitat Quantity Available for each Scenario Modeled (as a Percent of Current Conditions) was quite pronounced. 5

6 Deciding Barker Creek s Land Use Plan This decision support tool was fashioned to support the decision makers who were deciding the land use plan for the Barker Creek watershed. That decision was significantly influenced by the alternative futures planning process. While some citizens aspiration were at odds with the Conservative scenario, the discussions about those aspirations were largely framed in terms of the anticipated impact to the Barker Creek watershed. The Conservative scenario became the Watershed Subcommittee s preferred alternative and the recommendation of the Silverdale Advisory Committee. The Planning Commission concurred with the Advisory Committee, recommending it to the Board of County Commissioners. In December 2006 the Board adopted a land use plan for Barker Creek which was essentially the Conservative scenario. Significantly, the only place countywide where an existing urban area was made into a rural area was within the Barker Creek corridor. By creating the new rural area the community gained a separator between to urban areas (Bremerton and Silverdale), and Barker Creek took a step towards enhanced watershed health. CRITIQUE Figure 0: Groups Involved with Alternative Futures Planning and Growth Management Planning While this effort was successful in that it fulfilled its purpose of supporting a land use decision which was designed to be fish-friendly, it is not without its shortcomings. Models are used to try to simplify and describe complex natural systems; this comes at the risk of over-simplification and missing key factors. Using a GIS-generated parcel map to describe a landscape s land cover characteristics may not be accurate and does not account for other important factors affecting stream flow and watershed health. The HSPF model was criticized by citizens for not being able to factor in impacts of stormwater ponds. Stream flow results of modeled scenarios are second generation in that we have used one model (HSPF) to model results of another model (GIS). The RHABSIM model assumes a constant channel configuration over time. We know this is not the case in reality. One would assume that under Historic conditions a LWD-filled stream would have produced more chum spawning habitat than today, but the model showed a decrease in chum spawning habitat. Salmon habitat quantity for future scenarios are third generation in that we have used one model (RHABSIM) to model the results of another model (HSPF) which were modeled using another model (GIS). Compounding uncertainty may mean that these results are not as meaningful as they appear. The whole premise that this watershed s properly functioning conditions and beneficial uses can be protected and preserved by a land use plan may be false. Perhaps the damage is already done, but not yet manifesting; or perhaps this plan is relatively meaningless because it could be completely revised in the future. 6

7 Finally, it is possible that a similar land use plan for this area could have achieved without the expense of the alternative futures process. CONCLUSION In conclusion, the Barker Creek Alternative Futures planning process provided the needed technical basis and public support for adopting the preferred alternative in the County s Comprehensive Land Use Plan. The alternative futures process could be used successfully most anywhere where there is a will to engage the public and scientific community in identifying ways to manage land use for long-term resource health. Some key points to keep in mind: Pick a place where a significant decision is about to be made (this is a decision support tool!) Involve/educate key stakeholders Work within the existing framework (e.g., growth management regulations) GIS expertise is needed to create the alternatives Keep it as simple as possible (Simple = Able to Communicate with Public) Be opportunistic, find technical and financial assistance REFERENCES Kitsap County, 2005, Vision Statement. Kitsap County Department of Community Development, Factsheet: Barker Watershed Details. Washington Department of Fish and Wildlife, 2006, Barker Creek Instream Flow Study Final Report. 7