Dairy Creek Prospectus
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February 28, 2019 WETLAND MITIGATION BANK PROSPECTUS FOR: THE DAIRY CREEK MITIGATION BANK Located in Banks, Washington County, Oregon Sponsored by: Wolverine LLC 6770 Canyon Drive Portland, Oregon 97225 and Lone Oak Land and Investments LLC 34059 NW Mountaindale Road North Plains, Oregon 97133 Prepared by: C. Jonas Moiel, Senior Ecologist Green Banks LLC 14200 SE McLoughlin Blvd, Suite A Milwaukie, Oregon 97267 (503) 477-5391 TABLE OF CONTENTS 1. INTRODUCTION AND OVERVIEW………………………………………..1 2. SITE AND SPONSOR INFORMATION...................................................1 3. PURPOSE…………………………………………………………………….2 4. SITE SUITABILITY AND FUNCTION GAINS……………………………..3 4.1 Site Suitability…………………………………………………………3 4.2 DSL Principal Objective OAR 141-085-0680………………………4 5. TECHNICAL FEASIBILITY…………………………………………………..8 5.1 Soils…………………………………………………………………….8 5.2 Hydrology………………………………………………………………9 5.3 Vegetation……………………………………………………………..9 6. ESTABLISHMENT AND OPERATION…………………………………….10 7. LONG-TERM PLAN………………………………………………………….11 8. MITIGATION MARKET ANALYSIS………………………………………...11 9. SERVICE AREA………………………………………………………………12 MAPS AND FIGURES : Figure 1a: Site Location Map Figure 1b: Tax Lot Map Figure 2: NRCS Soils Map Figure 3a: Recent Aerial Photo Figures 3b-c: Historic Aerial Photos Figure 4a: Hydrological Degradation Map Figure 4b: Conceptual Design Map Figure 4c: Conceptual Vegetation Class Map Figure 4d: Conceptual HGM Class Map Figure 5: Service Area Map Figure 6: Topography Map from LiDAR (2007) DAIRY CREEK MITIGATION BANK PROSPECTUS i 1. INTRODUCTION AND OVERVIEW A mitigation bank is an aquatic habitat created, restored, enhanced, or preserved in accordance with state and federal regulations to compensate for unavoidable adverse impacts to wetlands and other aquatic resources, as authorized by the Oregon Department of State Lands (DSL) and/or the U.S. Army Corps of Engineers (Corps). This Prospectus for a mitigation bank has been provided to solicit comments from natural resources agencies, nearby landowners, and interested parties in order to identify issues of concern to be addressed in development of a more detailed Mitigation Bank Instrument, to be submitted for review and approval by DSL and the Corps. A DSL and/or Corps permit may be needed for construction of the bank. This wetland mitigation bank Prospectus was prepared for the Dairy Creek Mitigation Bank (DCMB) which is located in Banks, Oregon; within the Tualatin River basin. The proposed project site is approximately 134.1 acres and would be separated into Phases; Phase I being approximately 98.0 acres, and Phase II being 36.1 acres. The site is currently in agricultural production of grass seed (tall fescue), but was historically (pre-settlement) dominated by riverine and sloped wetlands that have been drained by agricultural tiling and ditching. The project site is directly adjacent to the eastern boundary of the Killin Wetlands Nature Park, an ecologically unique 590-acre wetland managed by Metro. The purpose of the Dairy Creek Mitigation Bank is to provide wetland mitigation options for private and public developers within the Tualatin River watershed. The potential for developing stream mitigation will also be investigated during the bank establishment process. 2. SITE AND SPONSOR INFORMATION The Dairy Creek Mitigation Bank is proposed on 134.1 acres located in Banks, Oregon (Figure 1); Township 2 North, Range 4 West, Section 36, utilizing a portion of tax lot 800 (144.40 ac); Longitude -123.121295, Latitude 45.616498. Much of the project area is within the 100-year floodplain of the West Fork of Dairy Creek. The northern to northwestern edge of tax lot 800 is bound by the West Fork of Dairy Creek. The DCMB land is owned by Wolverine LLC and the Lone Oak Land and Investments LLC. A new Limited Liability Company (LLC), the Dairy Creek Mitigation Bank LLC, will be established between both owners prior to project approval, which will serve as the bank sponsor. The sponsor team has contracted Green Banks LLC to manage the mitigation bank establishment and operations. Green Banks LLC is a natural resource consulting and land management firm that was established in 2008; located in Milwaukie, Oregon. Green Banks’ scientists have nearly 20 years of experience in environmental consulting, habitat management and mitigation banking. Green Banks is also the consultant and land manager for the Tualatin Valley Environmental Bank in Hillsboro, Oregon; and the Marion Mitigation Bank near Marion, Oregon. Green Banks has the scientific expertise to provide natural resource consulting services for bank establishment and management, as well as a staff of natural resource technicians that provide habitat management services such as chemical and mechanical weed control. Green Banks’ experience with the management of mitigation banks will help to ensure the success of this project. DAIRY CREEK MITIGATION BANK PROSPECTUS 1 Contact Information for project team: Sponsor: Wolverine LLC Sponsor: Lone Oak Land and Contact: Bob Bobosky, Member Investments LLC Phone: (503)292-8261 Contact: Marty Cropp, Member Email: [email protected] Phone: (503)939-3507 Address: 6770 Canyon Drive Email: [email protected] Portland, Oregon 97225 Address: 34059 NW Mountaindale Rd North Plains, Oregon 97133 Consultant: Green Banks LLC Contact: C. Jonas Moiel, Senior Ecologist Phone: (503)477-5391 Email: [email protected] Address: 14200 SE McLoughlin Blvd, STE A Milwaukie, Oregon 97267 3. PURPOSE The purpose of the DCMB is to restore, create, and enhance wetlands and upland buffers to generate wetland mitigation credits within the Tualatin River watershed. The goals of the project include: improving the functions provided from the wetland areas, increasing the acreage of wetlands, developing diverse native plant communities and buffers, and ensuring a mechanism for long-term protection and management. The primary objectives of the Dairy Creek Mitigation Bank include: • To improve and replace locally important wetland and stream functions through the removal of artificial drainage features and topography, and planting of native species. • Restoring wetland hydrology to historic wetlands through the de-activation of agricultural drain tiling and ditching. • Creating wetlands in areas adjacent to existing hydric soils with similar elevations and soil types through minor grading of approximately 6-inches or less. • Enhancing existing wetlands through the restoration of hydrology and conversion to native dominated plant communities. • Converting all of the Bank lands into native dominated plant communities. • Identifying a Long-Term Land Steward to manage and maintain the bank area indefinitely. The Bank sponsor would develop a long-term management plan and provide an endowment fund to the Steward prior to bank closure. The secondary objectives include: • Developing several unimproved perimeter access trails for vegetation management access and for passive recreational activities such as bird and wildlife viewing and walking. DAIRY CREEK MITIGATION BANK PROSPECTUS 2 • Investigating the potential to generate Stream Mitigation Credits. The State and Federal stream mitigation program is under development with a final guidance expected around the summer of 2019. The project area likely has potential for stream mitigation due to the historic straightening of the West Fork of Dairy Creek which caused the de-watering of the more sinuous channel. Some of the channel straightening occurred within the project area and there is potential to develop an intermittent side-channel which curves through a portion of the property. If it is determined that stream mitigation is an option, a separate prospectus may be developed and circulated for public comment at that time. It is predicted that the DCMB will generate roughly 88 wetland mitigation credits (Figure 4b); a more accurate estimate will be made after soils and hydrology studies are completed. This estimate is based on the Natural Resource Conservation Service’s (NRCS) soils mapping, a previous wetland delineation completed on the site, and a preliminary soils survey completed by Green Banks LLC. The existing hydrogeomorphic (HGM) classes of wetlands on-site include Slope/Flats and Riverine. The future HGM classes will remain the same; however, the wetland acreage will greatly increase (Figure 4d). The current vegetation within the project area is tall fescue (grass) and will be converted to Palustrine Emergent (PEM), Palustrine Scrub-Shrub (PSS), Palustrine Forested (PFO) wetlands, and uplands, based on the Cowardin classification system (Cowardin et al. 1979)(Figure 4c). Table 1 displays a summary of the proposed mitigation types and acreages. Table 1: DCMB Proposed Mitigation Types Type Acres Credits Restoration (1:1) (w/approx. 40% creation) 84.6 70 Creation (1.5:1) 21.3 14.2 Enhancement (3:1) 7.9 2.6 Buffers (10:1) 20.3 2 TOTAL 134.1 88.8 PFO 78.9 PSS 15.6 PEM 19.3 Upland Buffers 20.3 Riverine Flow-Through 55.4 Slope/Flats 58 Note: If stream credits are produced, the wetland and aquatic credit ledgers would be coordinated to ensure that the same functional gains are not sold to multiple markets. 4. SITE SUITABILITY AND FUNCTION GAINS 4.1 Site Suitability The proposed Dairy Creek Mitigation Bank is located in an area highly suited for ecological restoration. The existing wetlands have low functionality which can be greatly improved through the implementation of the project. The NRCS mapped 93.6 acres of hydric soils within the project area; however, most of the area