The URL can be used to link to this page

Home My WebLink AboutOriginal Townsite Block 4 - Eelgrass Restoration Planting Plan Northwest Maritime Center 2002.03.08Eelgrass Restoration Planting Plan Northwest Maritime Center (NWMC) Thomas Oil Dock Community-Based Habitat Restoration Battelle Marine Sciences Laboratory (MSL) Project #42546 Submitted to the Northwest Maritime Center March 8,2002 Eelgrass (Zostera marinal.) restoration at the Northwest Maritime Center Thomas Oil Dock is proposed to occur during the summer of 2003. According to recent dive surveys, eelSrass beds iurrentty exist at the proposed site approximat ely 12 tt (3 .66 m) to the northeast and 4 tt (L .22 m) to the southeast from the existing dock structure (37 ft [1 1.3 m] and 4 ft U.22ml, respectively from the proposed doc$ (Diefenderfer ?001). Eelgass will be planted at the site in an area coveringipproximately 4300 t( (400 m2), essentially connecting the two existing beds. The proposed ptunting includes a portion of the area in the footprint of the dock slated for removal. This effort will take three to five divers three to five days to complete. Figure I shows the existing eelgrass beds on both sides of the dock and the area proposed for planting. The area outlined in purple shows the area between the beds at the appropriate depth and slope for planting, while the area outlined in red is the proposed area for planting in a configuration ionducive to both planting and monitoring (i.e., square and measurable distances from the dock). NW M ariti lne.'Gente'r Thomas,O il a: Area planting'drea'' r-estqration Edgrass ,.8 Existing Doc-k 0,Meters, N "w - S Figure 1. Proposed eelgtass restoration area at the Thomas Oil Dock, F'urt Townsend, WA. Within the proposed 4300 tt @OO m21 planting area some areas will not be planted due to the high proportion of shell hash present in the substrate. According to dive surveys in the fall of 2}Ol,the highest concentrations of shell hash were located beneath the existing dock structure, Battelle Marine Sciences Laboratory, March 8, 2002, page I of 3 however, observations of shell were noted throughout most of the planting area (Diefenderfer 2001). In addition, planting will occur only in areas without existing eelgrass. Visible organisms (e.g., clams and macroalgae) will also be avoided during the planting process. While the exact areas for planting will be determined by divers during a pre-planting site assessment, a preliminary schematic of the planting plan is presented in Figure 2. Given the 2-year span between initial surveys on which maps were based, and the expected date of planting, eelgrass beds are expected to have shifted somewhat. NW Maritirne Genter Thomas Oil :i Restoration Area Proposed area Prirrrary area area Proposed dool Existing Eelgnss Existipg Dook I 0 0 Meters N-#E Figure 2. Preliminary schematic of eelgrass planting areas. The primary planting area to the east of ^the dock(474 tAV3 m211 and the primary planting area to the west of ttre do-ck (2443 f( 1227 m211 have fewer instances of coarse substrate and shell hash and will be planted at a density of 16 shootslmz 14 shoots per planting unit [PU] and 4 PU/m2) where feisible. Fonseca and others (1998) recommended plantingZ. marina on 0.5 m centerj, which is equivalentto 4PlJltr2. In the Pacific Northwest, Thom and others^(2002)have reported successful eelgrass restoration using planting densities rangrng from 12 to 24 shoots/m'. Planting the two areas on either side of the dock at this density will require approximately 4250 shoots. The remaining area (1410 ft2 tt:t m21;, located under a portion of the proposed dock, will be planted as feasible, avoiding pilings and areas of coarse substrate and/or deep shell hash. The goal is to plant approximately one third of this area at the same density discussed above, resulting in a shoot requirement of 750 shoots. Donor material for the planting will come from eelgtass cultured at the Battelle Marine Sciences Laboratory (MSL). This culture is funded in part through the Washington State Department of Transportation, which has agreed to donate 5000 shoots to this project. The general planting procedure will involve removing eelgrass from the MSL stockpile tank with intact rhizomes, assembling planting units, and placing the units in transplant plots as outlined by Thom and others (2001). Battelle Marine Sciences Laboratory, March 8, 2002, page 2 of 3 Once eelgtass donor material is collected, it will be held in cool seawater and only removed for short periods to construct the planting units and to place the units on slates for the divers. Each unit will consist of four eelgrass shoots attached at their rhizome to a 6 in (15 cm) wire turf staple using a paper-wrapped wire twist tie. Thirty units will be attached to each 12-in x 15-in (3d-cm x fb-cmf flexiglas slate using rubber surgical tubing and ffansported by the divers to the transplant plots. The slates will be placed in a cooler and floated over the subtidal planting location. Meter-square quadrats and tapes will be temporarily placed within the study area to determine density Jpacing. Divers will plant each unit by carefully inserting a trowel to a depth of 4-6in, angling the fiowel to create an opening in the sediment, and inserting the staple perpendicular to the sediment surface (rhizome paratlel to sediment surface). The sediment will itr"n U. pushed back to its original grade over the rhizomes and tamped down lightly by hand to secure the units. References Diefenderfer, H.L. 2001. Thomas Oil Dock Community-Based Habitat Restoration Project Field Survey Letter Report and Maps: Eelgfass Density, Macroalgae Cover, Bathymetry, and Substrate. Submitted by Battelle Marine Sciences Laboratory, Sequim, WA, to Northwest Maritime Center, PortTownsend, WA. November 14,2001. Fonseca, M.S., W.J. Kenworthy, and G.W. Thayer. 1998. Guidelines for the Conservation and Restoration of Seagrasses in the United States and Adjacent Waters. U.S. Department of Commerce, National Oceanic and Atmospheric Adminisfiation. Thom, R.M., G.D. Williams, A.B. Borde, J.A. Southard, S.L. Blanton, and J. Cordell. 2002. Habitat Mitigation Monitoring at the Clinton Ferry Terminal, Whidbey Island. Annual Report Number 5. Prepared for the Washington State Department of Transportation. Battelle, Pacific Northwest Division, Richland, Washington. Battelle Marine Sciences Laboratory, March 8, 2002,page3 of 3 11t C1171900++++Eelgrass Restoration AreawEIffiffiFr"qffiJPotential area for restorationProposed area for plantingExisting EelgrassProposed dockExisting Dock1720W2A Meters1 17195011720fi'1172100++_Thomas Oil DockPort Townsend, Washi ngton1290012850280012750e++Data Sources:Battelle Marine Sciences Lab: Shore to 10 m pastthe outer extent of the existing dock or the outerlimit of eelgrass (wtrichever farther); Sep 10-1 1 , 1 8Marine Survela and Assessments: Outer extent ofexisting dock to 20 m beyond existing dock; Sep 18State+++N*+850+9001 171950117200011720fiNorth, NAD 1983'12700 *s* *@1171950&+Aa&*s172000&+"20 Meters&&s_Thomas Oil DockPort Townsend, Washi ngton'l'|'720fi1172100+s12900128501280027506*#&ass+&&++Macroalgae Percent Covero NoneE Low (1-25Yolffi Moderate (26-65%)+ * High (>65%) +Eelgrass Restoration AreawEIffiffiffiPotential area for restorationProposed area for plantingExisting EelgrassProposed dockExisting Dock,k,#&Data Sources:Battelle Marine Sciences Lab: Shore to 10 m pastthe outer extent of the existing dock or the outerlimit of eelgrass (whicheverfarther); Sep 1G11, 18Marine Surveys and Assessments: Outer extent ofexisting dock to 20 m beyond existing dock; Sep 18Stde Plane,NAD 1983**o+s6N$&&++1 1718s01 1719001171950117200011720501172'lOO12700 lir<imil 6ii-Dcit EXSTING PROPOSED Nortnweif Miittiiie cCntei ooit< in-weter structure o\er-water slructure in-water structure o\,er-water structure piles dock piles dock grated gangway seasonal floats TOTAL PROPOSED Land to Odinary High Water Mark (O.H.W.)4 creosote 350lsf I 4isteel I 330 sf 330 sf O.H.W. to seaward side of Eelgnss beds 80 creosote 38'l l I isf 1 steelito: i 2465 sf sf seaward side of Eelgrass beds to deep water 0 : 0rsf iI 18 steel 1440 sf 1 sf TOTAL 84 creosote 4161 jsf i JO steel iI4235sf 1460isf sf "2 IXISTING STRUCTURES REMOVED ( ( /\/\ .u--'.")--' '///' 6r{rd \./ tao. -(oq .6 -e$s$'}: 's' ( do. !..\a a TXISTING EETGMSS BEDS PROPOSID EELCMSS RESIOMTION PI-A}.{TING AREA IXISTING IHOIIAS OIL DOCK TO BE RTMOVTD NEW FLOATING DOCKS FOR SMALL CMFI IIUNCH /,.\L-V-- AREA CALCULATIONS--EXISTI NG VS. NEW OVERALL PLAN SGALE:1/32"=1-0"01 J0-elevotions.dwg '/Err __-_- 0 8 16 32F1 0-JJo-Ec ii9.E N oc Eco ohtr ElE E*= s e9i e is9€ F< =o 652= O,- oi >=!; -EF<;6 N (? Nq I t tuFz LtJ c) UJ Et F U) tu =IFtoz ETECIRICAL ED DAVID J 0mego Engineering 724 Ericksen Ave. Suite 201 Boinbridge lslond, WA 98110 855-4600 tel 855-4601 lox SIRUCTURAL Dovid Pierce PND 811 first Ave. Suite 260 Seottle WA 98104 (206) 624-1J87 ter (206) 624-1JBB fox dpierce@pndseo.com Revisions Date lssue Doie Morch 2002 Drown BcChecked CC MIH Pro.iect No. 01J0 Cod File (206) (206) edovid@jomegoengineering.com zotro-lcft.2F.c 9EoEOEUJEtr2\./ 36POEo; OVERALL PLAN A1 .2 INIERPREIVE PNEL: tELGMSS RESToMT|0N' A -.or ) .\_g\ ENENT OF DOCK TO BE REMOVED PROPOSED AREA FOR IILGRASS RTSTORATION PI.ANIING PLAN ALUMINUM G,qNGWAY (6'xeo'), GMTEDy{AtxtNG sujt$9f ,tto q a E\ ACCESS IADOER MAST CMNE INTERPREIIVE PNEL: "LIGHT IECHNOLOGIES, INTERPREIIVE PANEL: 'PORT TOWNSEND,S MARIIIME HISTORY, S]RUCTURE BELOW ENLARGED DOCK, GANGWAY AND FLOAT PLAN SHOWN DASHED SCALE:1/16"=1-0" *'ffi-?ur,. II I)II L(, II.I LJJ.9o ^cc -E.E Noc Ec6 0 hL d(Llt -- NN - C gs Qoiir iFs*bi a-;3 Fo;5Ndi2= O --oi >i c;v-60r-t -oEdF< 6ocI zaFo -lctP-F.E Q.6z-6o=Oorrj EE.?\./ =6POEod M tuFz tuo tIJ Et t-a tu 3IFtoz ELECIRICAL ED DAVID J Omego tngineering 724 Ericksen Ave. Suite 201 Boinbridge lslond, WA 98'110 (206) 855-4600 rer (206) 855-4601 fox edovid@jomegoengineering.com STRUCiUML Dovid Plerce PNO8ll First Ave. Suite 260 Seottle lt/A 98104 (206) 624-1387 tel (206) 624-1J88 fox dpierceOpndseo.com Revisions Date lssue Dote Morch 2002Drown 8c Checked MIH Project No. 01J0 Cod File ENLARGED PLAN & SECTION 41 .3