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HomeMy WebLinkAboutLog207 Parametrix ENGINEERING. PLANNING. ENVIRONMENTAL SCIENCES 41110&th AVENUE NE, SUITE 1800 BELLEVUE, WA 98004-5571 T. 425 . 45&. 6200 F. 425 . 458 . 6363 W\"!.'W.paramctdx.com January 31, 2006 PMX No. 553-1820-010 02/01 David Johnson Jefferson County Department of Community Development 621 Sheridan Street Port Townsend, Washington 98368 Re: Marrowstone Island Water System (MLA 05-00276) Wetland Delineations Dear Mr. Johnson: I am writing to respond to comments provided by Janet Welch in a letter dated December 22, 2005 regarding the Phase 1 wetland delineations for the proposed Marrowstone Island Water System. I would also like concurrence from the Department of Community Development (DCD) that the Phase 1 wetland delineation methodology, impact assessment, and proposed mitigation measures are consistent with the Jefferson County Unified Development Code and DCD permitting requirements. Parametrix has been retained by Jefferson County Public Utility District Number 1 (PUD No.1) to identify wetlands and other environmentally sensitive areas on or near the alignment of the proposed Marrowstone Island Water System. As you are aware, the water system will be constructed in phases and Phase 1 includes the installation of an 8-inch-diameter water main over the length of the island. South of Fort Flagler State Park, the main will be installed either along State Route (SR) 116 (in the bottom of the roadside ditch) or along county roads (in the road shoulder). Parametrix conducted a wetlands reconnaissance survey in July, 2005 of all the roads identified for potential water system installation by PUD No. 1 and in August, 2005, delineated four wetlands within the Phase 1 project area. A copy of the Phase 1 Wetland Delineation Report (Parametrix 2005) has been provided to you. In her letter, Ms. Welch raises concerns about the adequacy of the wetland delineations and impact assessments described in the Phase 1 Wetland Delineation Report (Parametrix 2005). Specific issues identified in her letter will be addressed below. I respectfully disagree with her contention that the Phase 1 wetland delineation does not adequately identify wetlands and buffers in the project area. To summarize her argument, she believes that all wetlands within 150 feet of the proposed work areas should be delineated to accurately assess wetlands and the associated buffers proscribed by the UDC. I believe the Phase 1 wetland delineation does adequately identify wetlands in the project area because potential wetlands were identified from the Jefferson County wetlands map, National Wetlands map, aerial photographs, and a wetland reconnaissance survey prior to the delineations for Phase 1 and also because project impacts will be limited to the existing, maintained road right-of-way (ROW), which does not provide high quality buffer functions. LOG ITEM # 'LOT Page~LotS- David Johnson January 31,2006 Page 2 The UDC defines a public road (ROW) as 60 feet in width (~18.30.080(1)) (i.e., 30 feet wide on each side of the centerline) and recommends installing utilities within the transportation ROW to minimize adverse environmental impacts (~18.30.120(1)). The UDC (~18.15.215(1)) also allows for existing legal nonconforming uses within designated critical areas buffers at the time the code became effective. All of the roads within the Phase 1 project area were in existence at the time the current version of the UDC became effective. For safety and to maintain roadbed integrity, roadside vegetation and the drainage system require periodic clearing (WSDOT 2004a). Washington State Department of Transportation (WSDOT) vegetation management guidelines recommend clearing trees within 15 feet of the edge of pavement to maintain sight distance and motorist safety (WSDOT 2004a, b). Installation of the Marrowstone Island Water System will not result in the clearing of vegetation beyond the regularly maintained road ROWand therefore, will not adversely impact the existing buffer within the ROW. For reference purposes, line numbers have been added to Ms. Welch's letter, which is included as an attachment. Specific issues raised in the Wetlands Delineation Methodology section of Ms. Welch's letter will be addressed by line number. These issues include: Comment 1 Page 2, Lines 52-54: Delineation methodology does not accurately or sufficiently identify wetlands or buffers in the project area. Response 1: As stated on page 2-1 in the Phase 1 Wetland Delineation Report (Parametrix 2005), wetlands were delineated using the methodology specified in the 1987 Corps of Engineers Wetland Delineation Manual (Environmental Laboratory 1987) and the Washington State Wetland Identification and Delineation Manual (Ecology 1997). These manuals are the standard for wetland delineations in Washington state and meet the delineation requirements of the UDC (~ 18.15.325). The survey area for the Phase 1 wetland delineations was limited to within 20 feet of the road edge in order to identify wetlands potentially impacted by project construction. The project area for the Marrowstone Island Water System was defined by the PUD as the road and associated ROW. Parametrix did not have and did not seek permission to delineate wetlands on private property beyond the ROW. Wetlands that extend beyond the subject property are not required to be delineated. For wetlands extending off-site, wetland size, vegetation classes, and connectivity may be estimated from orthophotographs and other resource materials (Hruby 2004). Comment 2 Page 3, Lines 2-4: Delineation should extend 150 feet from the project footprint to characterize buffer. Response 2: Potential wetlands within approximately 150 feet of the proposed work areas were identified prior to the Phase 1 delineations from wetland maps, aerial photographs, and from a reconnaissance survey. Since the project will not adversely alter the buffer within the maintained ROWand because the ROW is a legal nonconforming use, it is not necessary to delineate 150 feet out from the project footprint. Comment 3 Page 3, Lines 5-7: Claim that project is not in a wetland buffer. LOG ITt:i~1 # 20"1- Page _ ..L. of~.5- David Johnson January 31, 2006 Page 3 Response 3: The Phase 1 delineation report does not claim that the project is not in a buffer. The delineation report does state that there will be no direct impacts to regulated wetlands and that wetland buffer impacts will be limited to the maintained ROW (page 4-1, ~ 4.1). Comment 4 Page 3, Lines 11-14: Contradictory claims for water main installation (road shoulder versus ditch bottom) in delineation report and the assumption that non-exempt activity will be enabled by exempt activity (mowing). Response 4: The delineation report clearly states that the water main will be installed by open-trenching within the ditch bottom along SR 116 and the shoulders of county roads. Where the county road shoulder width is inadequate to avoid impacts to environmentally sensitive areas from open- trenching (page 1-2, ~ 1.3), the main will be installed with horizontal directional drilling (HDD). The delineation does not assert that the water main installation is, or should be, an exempt activity. The report states that the main will be installed within the maintained ROW. Routine and ongoing ROW maintenance involves a number of vegetation control measures including mowing, herbicide spraying, vegetation removal, tree trimming, grading, and ditch excavation. Mowing is perhaps the most frequently used of these maintenance activities and was the example cited in the delineation report. Ms. Welch is correct in stating that mowing, an exempt activity should not be the justification for the main installation, a non-exempt activity (Page 2, Lines 52-54). ROW maintenance (mowing) is mentioned in the delineation report because of its effect on the wetland buffer. The buffer within the maintained ROW is perpetually disturbed and does not provide a high level of buffer function or habitat value. Installation of the water main will not alter the maintenance of the ROW or the existing functions provided by wetland buffers within the maintained ROW. Periodic vegetation removal and ditch excavation within the ROW will continue regardless of water system installation. PUD No.1 is not asserting that the water system installation is an exempt activity. The wetland reconnaissance and delineation surveys have been conducted to comply with the requirements of the UDC for project work in or near environmentally sensitive areas. Results of the delineations are being incorporated into the construction plans to avoid and minimize impacts to environmentally sensitive areas. Comment 5 Page 3, Lines 26-29: Accurate wetland classification requires identification of wetland outside of project area. Response 5: In classifying wetlands delineated for Phase 1, the full wetland extent was identified and considered by reviewing aerial photographs, National Wetlands Inventory maps, Eastern Jefferson County Wetlands map, and the Jefferson County Soil Survey. Use of these additional resources is described in the delineation report (page 2-1, ~ 2.1; page 2-3, ~ 2.2.2), is consistent with the UDC requirements (~18.15.340(2)(b)), and is recognized by the Washington State Department of Ecology as an accepted practice in classifying off-site wetlands (Hruby 2004). Comment 6 Page 3, Lines 31-33: Delineation methodology fails to accurately describe wetland buffers impacted by pipeline installation. # Page LOG ITEM LO-:r 3 ot5- David Johnson January 31,2006 Page 4 Response 6: The delineation report states that wetland buffer impacts will be limited to the maintained ROW (page 4-1, ~ 4.1) (see Response 4 above). Comment 7 Page 3, Lines 35-37: Delineation (report) is contradictory in stating work within wetlands will be avoided and then stating HDD will be used for main installation in sensitive areas. Response 7: Stating that there will be no work within wetlands and using HDD for main installation in sensitive areas is not contradictory. HDD is the preferred construction method for utility installation in wetlands and watercourses (Cameron et al. 2002; Hair et al. 2002; Heffron 2004; Fisheries and Oceans Canada 2005). With HDD, the utility line is placed several feet beneath the sensitive feature by boring (drilling) beneath the feature, which minimizes the risk of disturbing the ground surface within the sensitive area, thereby reducing or avoiding the increased turbidity, soil disturbance, and vegetation clearing associated with open-trenching. Comment 8 Page 3, Lines 43-46: Delineation report only addresses Phase 1 (main installation) impacts. Response 8: As stated in the first 2 paragraphs of the delineation report (page 1-1, Introduction) and in Section 1.4 (page 1-2), the delineation report describes wetlands and shorelines within the Phase 1 project area. Phase 1 of the Marrowstone Island Water System, as defined by PUD No.1, involves only the installation of the main. Installation of the remainder of the water system will be addressed in subsequent wetland surveys and reports. Thank your for reviewing this letter. PUD No.1 has retained Parametrix to identify environmentally sensitive areas potentially impacted by project construction and to assist the PUD in minimizing these impacts. The PUD is committed to constructing the Marrowstone Island Water System in a manner that meets the regulatory requirements of Jefferson County, state, and federal regulatory agencies while at the same time allowing for the timely and cost -efficient implementation of the water system. I would appreciate your written comments on the responses to Ms. Welch's concerns and the delineation methodology, impact assessment, and mitigation measures described in the Phase 1 Wetland Delineation Report (Parametrix 2005). I believe it is in DCD's and the PUD's best interest to identify potential concerns and issues with the critical areas studies prior to initiation of the Phase 2 wetland delineations. If you have any questions, or require any further information, please contact me. Paul S. Anderson Wetlands Biologist/Project Manager Parametrix (425) 458-6279 LOG ITEM # LO-:t- Page~ot ~. References: Ecology (Washington State Department of Ecology). 1997. Washington State wetlands identification and delineation manual. Publication Number 96-94, Olympia. Environmental Laboratory. 1987. Corps of Engineers wetland delineation manual. Technical Report Y-87-l, Environmental Laboratory, Department of the Army, Waterways Experiment Station, Vicksburg, Mississippi. Heffron, M. 2004. Challenges associated with horizontal directional drilling and piping installation under a major highway for the remediation of a petroleum plume. Tetra Tech FW, Inc., Langhorne, Pennsylvania. Available online at: http://www.tteci.comlHeffron2004.pdf. Accessed October 14, 2005. Hruby, T. 2004. Washington State wetland rating system for western Washington-Revised. Publication Number 04-06-014, Ecology, Olympia. Parametrix. 2005. Pinal Marrowstone Island Water System-Phase 1 Wetland Delineation Report. Prepared by Parametrix, Bellevue, Washington. November 2005. WSDOT (Washington State Department of Transportation). 2004a. Integrated vegetation management, maintaining roadside vegetation, poster. Maintenance Division, Olympia. WSDOT (Washington State Department of Transportation). 2004b. Island County roadside maintenance and weed control. Maintenance Division, Olympia. LOG ITEM # &01- Pag'3 ~5:.-. ot t;