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Koll North Creek - 1992 Monitoring Report Backwater Wetland Creation Enhancement Plan . . . 1992 ANNUAL MONITORING REPORT KOLL - NORTH CREEK BACKWATER WETLAND . CREATION/ENHANCEMENT PLAN . For . The Koll Company 19515 North Creek Parkway N. Bothell, Washington 98011 . by . IES Associates 1514 Muirhead Avenue Olympia, WA 98502 ( 206) 943-0127 FAX (206) 943-2791 December 7, 1992 . . . RECEIVED DEe 1 0 1992 CITY OF BOTHELL COM. DEV. . . Introduction . . In the fall of 1991, the backwater wetland area of the Koll - North Creek project was sprayed with Rodeo to kill the reed canary grass in the 5 acres, extending from the south end of the backwater wetland out-flow area, north to a point where North Creek overflows during high flood periods into the backwater wetland. The purpose of the spraying was to kill as much of the reed canarygrass and its rootstock as possible, prior to grading. . . The area was graded, being lowered on an average of 1 to 2 feet, across the site, removing reed canarygrass and lowering the elevation to a point where it was consistent with the 45 CFS line in North Creek, just north of the backwater wetland area. The main island in the south-central portion of the site was retained. The general contours were retained only lowered. The overflow weir was moved from the north end of the site to the south end and installed with a notched log to regulate the out-flow of water, yet allow salmon to escape the wetlands as the water decreased. (Photograph # 3) . . A sloped, rocked drainage was dug from North Creek, with the invert elevation equal to the 45 CFS line through this section of North Creek. . With this scenario, water now flows into the wetlands anytime North Creek exceeds 45 CFS, as compared to the previous system, which required the stream to exceed 150 CFS before water entered the backwater wetland. The water is . 1 . . . 1992 Annual Monitoring Report Koll - North Creek Backwater Wetland December 7, 1992 . blocked by the exit weir, backing the water up and holding it at a depth of 2 to 3 feet (depending upon the location) through the wetland. Water is metered out of the wetland to the south, by the notched weir log. It re-enters North Creek along its east-west reach. . Under this scenario, when the flood water reaches 150 CFS, it will back into the wetland from the south, until it reaches the weir. Water entering from the north will mix with this water, blanketing the wetland area, creating a 5.5 acre pond. As the water decreases, the water south of the weir drops rapidly with the creek elevation; whereas, the water north of the weir is metered out through the structures. ! . . . Under the current design, water will be retained north of the weir for a minimum of 96 hours after each event. This means that after the last rainfall in the spring, there would be a period of 96 hours, from the time the water stopped flowing into the wetland at the north, until it stopped flowing out of the wetland to the south. As long as water continues to flow into the wetland at the north end, the time release continues, which creates standing or intermittently pooled water on the wetland. . . A watering system was installed to sprinkle irrigate during the first two growing seasons or until wetland emergent vegetation had become established on the site. This was intended to increase the wetness of the area in an effort to enhance the survival of wetland plugs and seed, and to allow it to compete more effectively with reed canarygrass. . 2 . . . 1992 Annual Monitoring Report Koll - North Creek Backwater Wetland December 7, 1992 1992 Maintenance . . In the spring of 1992, spot spraying of reed canarygrass was initiated and continued (with Rodeo) through the early portion of the summer or until the reed canarygrass had become so intertwined with other species, that control would impair the spread of competitive species and eliminate the diversity we were seeking with the enhancement/restoration plan. 1992 Planting Plan . . During the spring of 1992 additional soft rush (Juncus effusus), slough sedge (Carex obnupta), willow-weed (Polygonum lapathifolium), and three-square bulrush (Scirpus americanus) were plugged or seeded onto the site. The entire site was then over-seeded with a mix of redtop (Agrostis alba), meadow foxtail (Alopecurus pratensis) and red fescue (Festuca rubra). This planting and seeding was a supplement to the planting and seeding that took place in the late fall of 1991, as part of the approved restoration plan. New planting added an additional 10,000 plants and 150 1bs of seed to the area. . I. 1992 Monitoring . Monitoring was initiated in January 1992 to evaluate the flood/detention system to see if it was meeting the proposed goals and objectives of the Revised Restoration Plan. The total days of total inundation were recorded. .Total days when there was 75% inundation, 50% inundation and 25% inundation were also recorded. The dates of rejuvenated flooding were . 3 . . . 1992 Annual Monitoring Report Koll - North Creek Backwater Wetland December 7, 1992 noted and a curve was created showing the frequency and duration of flooding. . The area was photographed at different document physical conditions. These photos are Appendix A. periods included to as . . Vegetation was monitored in April, May, June and October, 1992. The survey included: species composition and distribution; density; height; percent of non-native invaders; and wildlife use. . In April, it became apparent that the major competition for survival of wetland plants planted and seeded into the site was waterfowl and shorebird use and not invasive non- native species. Through April to late June, the waterfowl and shorebird use on the area was consistent. The dominant species was western sandpipers, dunlin, mallard, pintail, green-winged teal, cinnamon teal, gadwall and Canada geese. Plant survival during this period appeared to be low; however, inspection of the roots of planted material (other than cattail) demonstrated that plants were still viable and growing. (Photographs, Appendix A) . . . Bird use on the area was recorded, as it has been for the past 5 years. A table of bird use and waterfowl use on the backwater wetland and stream bank are included as Tables 1 - 3. In July and August, when shorebird and waterfowl use decreased, the plants that were planted on the site were able to sustain growth and reach maturity. Plants species which were dominant in one or more of the areas were: three-square . 4 . . . 1992 Annual Monitoring Report Koll - North Creek Backwater Wetland December 7, 1992 . bulrush, river bulrush (Scirpus fluviatilis), soft rush, slough sedge, creeping spikerush (Eleocharis palustris), willow-weed and water smartweed (Polygonum amphibium). . Reed canarygrass has re-established itself on the northern end, in the overflow apron, where the water first enters the site from North Creek. A portion of this area is adjacent to the stream bank vegetation along the west side of the creek, which is predominantly a reed canarygrass stand. Black cottonwood (Populus trichocarpa), Pacific willow (Salix lasiandra) and Si tka willow (Salix sitchensis), which were planted on the site, have maintained their vigor and are growing. In addition, black cottonwood and hardhack (Spiraea douglasii) have become established in two different areas in the northern part of the wetland, creating a precursor of a tree/shrub wetland community, which may dominate a portion of the site. . . . One of the large weeping willows, that was planted during the original scheme, has died and is being used by birds as a perch area (Photograph #21). . . A plant distribution map, indicating the approximate areas with ~ifferent dominant species, is included as Figure 1. A total list of plants with their dominance, ei ther "abundant", "common", or "uncommon", is included as Table 4. . Based on the requirements of the City of Bothell Permit and the Army Corps of Engineers, Section 404 Permit, it is the opinion of IES Associates that the wetland has developed to a 5 . . . 1992 Annual Monitoring Report Koll - North Creek Backwater Wetland December 7, 1992 . sustainable, diverse, wetland community, which is providing excellent waterfowl, shorebird and other water dependent bird activity on the site. . It the opinion of IES Associates that the area has satisfactorily met the conditions of the permits, as of November 15, 1992. . In the summer of 1992, the overall project was evaluated and a joint report was developed by IES Associates and the Watershed Company. A paper was presented at the International Society of Ecologists conference in Columbus, Ohio. An abstract of the report, with tables identifying the biological use of the area over the past five years, is included as Appendix B. '. R. L. Van Wormer Senior Biologist IES Associates . . . . 6 . . . . . Backwater Wetland/Stream Bank . Waterfowl Use Pre- Peak Use Total Canst Numbers Days Broods Young . Year 1 50 2,250 0 0 Year 2 850 47,500 10 53 Year 3 1,140 63,400 16 72 . Year 5 900 64,000 15 68 . . . . . TABLE 1 . . . . TABLE 2 ,. . Stream Bank Nesting 1 Non-Waterfowl . Species Year 1 Year 3 Year 5 Common Bushtit 0 0 2 . Fox Sparrow 0 3 2 Junco 1 4 5 Long-billed Marsh Wren 0 2 3 . Robin 4 4 7 Rufous Hummingbird2 0 0 1 . Song Sparrow 1 3 6 Starling 0 0 2 Towhee3 0 2 6 . White-crowned Sparrow 1 0 0 Winter Wren' 0 3 5 Yellowthroat 0 3 7 . 1 Based on limited surveys. 2 Only nest located. . 3 Based on young birds. . Based on territorial males. . . TABLE 3 . I , Table 4, List of Existing Plants In Restoration Wetland . Method of Introduction' Botanical Name Common Name . Trees '. N . . . . . Populus trichocarpa Sa11z Babylonlca Sal1z l..iandra Populus tremuloidea Alnus rubra Thuja plicate Black cottonwood Weeping Willow Pacific willow Quaking aspen Red alder Weatern red cedar Shrubs . . . . Sitka willow Scouler willow Red-oaier dogwood snowberry Sallx altchenaia Sal1z acouleriana Cornua atolonifera symphoriearpoa Albus . Other . . . ',N . . '.N N N N N P P . N N N . . N N N N N Ranunculus repens Ranunculus acris . Willow-weed Three-square bulrush River bulrush Soft rush Small-fruit bulrush Slough sedge Creeping spikerush Three-atamen rush Toad rush Sierra rush Bal tic rush Broad-leaf cattail Hard-stem bulrush Canada mint Spearmint Reed canarygrass Common velvet grass Redtop Creeping bentgr.as Field horsetail Fireweed [not fireweed] Creeping buttercup Meadow buttercup . Polfgonum lapathifolium Seirpua amerie.nu. Scirpu. fluviatilia Juncu. affuaus SCirpu. microearpua Carex obnupta Eleocharis paluatria Juncua enaifoliua Juneua bufoniua Juncu. nevadenaia Juncu. balticua Typha lattfolh scirpu. .cutU8 Mentha arvenaia Mentha Phalaria arundinacea Holeua lanatu. Agrosti. alba Agrosti. palu_tria Equiaetum arvenae Epilobiua &nguatifolium . . . 'p = Planted; N= Naturally Introduced Location2 Occurance3 HC, A NC, U . U I N,S U W. U . p,wp I,N,WP I All NC,E,W,WP HC,R.W N,NC,WP,S S HC,WP NC HC,S HC,E,S,WP NC HC,! S,WP S,WP HC,! NC N,E,WP,S N,NC N,NC,R,WP N,NC N,WP,! N,E,WP N,NC E,WP,S E,WP C U C U A A A A U C U U U U U C U U U C C C U U C U U U 2 Location in wetland N=north end; I=Island; NC=north- central (north of island); E-east (east of island); W=west (west of iSland); P=peninsula (west of island); WP=west of peninsula; S= south end; WA=Weir area . 3 A= abundant; C= common; U- uncommon . ,. . 1992 Annual Monitoring Report Koll - North Creek Backwater Wetland December 7, 1992 . I I . Appendix A - Photographs . . I . . . I . 7 I. . . 1992 Annual Monitoring Report Koll - North Creek Backwater Wetland December 7, 1992 . Appendix B - Abstract Of Report . . . . . . . 8 . . . STREAM AND WETLANDS CREATION, RESTORATION AND ENHANCEMENT NORTH CREEK, WASHINGTON Van Wormer, R. L. and Way, W. W. 1992 . . In 1982, the KolI Company initiated a study to evaluate wetlands and a channelized section of North Creek in the vicinity of Highway 405 and 195th Street in Bothell, Washington, U.S.A. Initial studies included: . . 1. A topographic survey by Horton Dennis Associates, Kirkland, Washington, to determine the elevational difference between the upstream border of the property and the point where the stream left the property. . I 2. A wetlands identification, delineation and classification by IES Associates, Olympia, Washington. A values analysis and potential impacts analysis were also determined. . 3. Soil surveys to determine the depth and extent of known peat beds by Earth Consultants, Kirkland, Washington. . . 4. A computer modeled potential stream channel was completed by Timberline Association, Boseman, Montana and the Watershed Company, Kirkland, Washington. . . . The project site was an abandoned truck farm that had been ditched for drainage and plowed annually for over 50 years. North Creek had been placed in a vertical banked channel with farm roads along both sides. Through this area, the creek supported 2 species of salmon, steel head and cutthroat trout. The center of the property contained a large peat deposit, nearly 80 feet deep at the deepest location, and approximately 5.5 acres of mixed wetlands. . . . The proposed mitigation plan included (1) the movement of the creek channel to a meandered configuration around the side of the deep peat deposits, (2) the creation of replacement wetlands and (3) the creation of a wetland storm water detention and purification system. . The model stream increased the stream length by 1,000 feet and created 18 ponds and 17 pool and riffle systems using of a variety of log, rock and root mass structures. . . The wetlands were divided into two segments: (1) the wet riparian border of the stream and (2) a backwater overflow emergent marsh. The pond/detention system consisted of a deep peat-lined pond with a shallow, overflow marsh apron and a biofiltration outlet channel. All site water and upstream dairy farm run-off was directed away from North Creek into this system by a series of underground pipes. . . 2 . . . In 1983, permit negotiations were initiated with the Army Corps of Engineers (ACOE) , Environmental Protection Agency (EPA) , Washington Department of Fisheries (WDF), Washington Department of Wildlife (WDW (Game)) and the City of Bothell, Washington. Permits required included: . . 1. Section 404, Dredge and Fill Permit. 2. State of Washington Hydraulic Permit approval (HPA). 3. City of Bothell Grade and Fill Permits. 4. Section 401 Water Quality Certification . Permits for the stream channel, based on the model and projected water quality and fish and wildlife improvements, were readily attained from WDF and ACOE. . Permits for the wetlands were more cumbersome because of conflicting agency interests. The original wetland design included ponds, marshes and a shrub/tree marsh area. The plan included the entrapment of winter stream flow to form the ponds, shallow marshes and wet swamps and meadows. WDF refused to issue the necessary permits for this system or any system that included the potential entrapment of anadromous fish. . . . Federal Emergency Management Agency (FEMA) opposed the inclusion of the additional vegetation in the flood plain. Their contention was that it would increase the flood friction coefficient, raising the potential for future flooding or erosion of a dike system. . 3 . . . Through negotiations with WDW (Game), WDF, ACOE and the consultants, a backwater wetland was designed that allowed the water to back into the wetland anytime water exceeded 75 cfs (U.S.G.S flow gauge, 35-year average summer low flow). At 150 cfs, the water would overflow an upstream sill and flow through the wetland. As the water receded, the water would leave the wetland, preventing the possibility for fish entrapment. . . The project was constructed during the fall/winter of 1984-85. The stream channel was dug in the dry and gradually flooded through a staged diversion. The old'stream was blocked at the outflow, forcing all water to flow into this dead-ended channel or the new stream. The old stream was shocked to remove all fish before it was completely dewatered. The diversion occurred in the summer of 1985. . . . Stream bank vegetation and the backwater marsh and detention pond were planted during the fall/winter 1984-85. Large-sized plants were used to maximize bank stabilization and shade during the first summer after diversion. . Monitoring was initiated during the spring of 1985 to determine the success ratio of the stream, vegetation and water quality. Studies included: . 1. Fish studies to determine numbers of salmonids and redds. 2. Vegetative success. 3. Goals accomplishment. 4. Water quality at the retention pond outlet. . 4 . . . Electrofishing was conducted on a 100-foot section of the to-be- relocated channel and on a 1 DO-foot control section located just upstream in October 1984 and August 1985. On October 22, 1987, and again on October 4 and 5, 1989, follow-up data was collected by electrofishing the original control section and two 1 DO-foot sections of the relocated North Creek channel. Changes in salmonid fish populations between 1984 and 1989 are compared in the accompanying table (Table 1). Salmonid fish populations in the test sections at Stations 5 and 11 are compared to those from the old channel before 1985, since the old channel section was abandoned and the test section at Stations 5 and 11 were created at that time. . . . . In addition, spawner surveys were conducted on four days, one month apart, in the fall of 1984 with no redds observed on-site. Follow-up surveys were conducted on October 21, 1987, and again on October 17, 1989. Seventeen adult salmon and 12 redds were observed on October 21, 1987, consisting of 12 sockeye, 3 chinook and 2 coho. Of the redds, one was presumed to be chinook and the remainder were presumed to be sockeye redds due to their size and the date. On October 17, 1989, a live coho and sockeye and a chinook carcass were observed. The sockeye appeared to be a spawned out female guarding her redd, the only redd observed on that date. Though the spawner survey data and the electrofishing data both indicate a generally lower level of fish use in the fall of 1989 compared to the fall of 1987. fish use remains substantially higher in North Creek on the KolI property than it was before it was relocated and rehabilitated. . . . . 5 . . . Stream bank vegetation and vegetation around the detention pond met goals and performance standards. . However, the low-flow channel flow averaged only 38 cfs between 1985 and 1988, virtually eliminating flooding of the backwater pond. The projected 276 days of flooding was reduced to 86, with the longest duration being 10 days. The wetland provided good water treatment and supported high numbers of waterfowl, shorebirds and mammals, but it did not meet the goals of the plan. . . In 1991, the wetland was graded two feet lower and the outlet structure and intake were altered to allow all flows in excess of 40 cfs to pass through the wetland. The outlet was raised and notched to allow fish escapement. In two years, the wetland has started to recover and provide the plant and water depth diversity planned. Portions of the area have met standards, while other areas have been converted to mudflat areas which were not a part of the original plan, but were included in the redesign to provide shorebird and dabbling duck habitat. . . . The wetland, riparian border and pond are providing improved fish and wildlife values, as well as stream health improvement by lowering in-stream water temperature by 1 to 2 degrees (F.) and reducing downstream sediments and coliform concentrations. The increased level of fish use supports the conclusion that the in-stream fish habitat has improved as a result of the relocation. The trees and shrubs planted along the banks of the relocated portions of North Creek have continued to flourish, thus providing . . 6 . . . ever increasing levels of shade and cover to the creek itself. Rearing habitat, in particular, should continue to improve on the site as stream side vegetation continues to proliferate, providing shade, cover, food and habitat diversity. . . Van Wormer, R. L., President/Senior Biologist IES Associates, Olympia, Washington 98502 Way, W.W., Owner, The Watershed Company Kirkland, Washington . . . . . . 7 . . . :; 8 NMII) 13~ MI/)'" ~N"": "':..tM . 0 .j.J III ~ '0 Q) Ql Cl ~'> H c: Mr-. ... (II ...r-.N '" I=~ .,.M... .,.CD.,. .,.r-.II) 0. III ciciN ciNci cicici E ~ 0 . 0 0 c: Q) H 0 m '" . :;:; c: III 8 c: 0 - 0..... ::J ~I:J~ t3111~ lRlRf;; .....Ul Co UlH . 0 H Q) Q) > a. ~CIl >..... .....'0 ~ Il'~ 'OQ) III ii: CD r-. H H ~~ II)MII) N . (II ... Q) 0 't:I NlOci 0'" r-. . . .j.J.... .- N... ...1/)'" ....Q) . c: ",.0 0 ~~ E Q) Q) Ii; c C III C c: en ",'" 8 ~~~ ~I::~ .c.c l!313~ 00 .... :J'O . Q) Q)~ .0 CO III ~ Q) Q) .- .c.c .j.J.j.J 8 0 .., I I .,. c:C: ... ... 0 ... I I ... .......... . Ul Ul c: c: 00 .......... .j.J.j.J ",'" ~~ ~a; :3 :3 0.0. a; a; 00 . c... c... Cc... Iloo. C... I/) 0 C...I/)O ~. :; ... I/) 0 ra ra .. .cc:c:c: .cc:c:c: ~.cc:c:c: 80.2.2.2 ~0.2.2.2 0.2.2.2 "tJ........... -a7iinia; _"C"CUn;-;Q rarara t:oiiiiiiiii -...._- <oiiiiiiiii OCl)CI)CI) . . . . Table 2: Stream Bank Nesting' Non-Waterfowl . 1 Based on limited surveys. Only nest located. Based on young birds. Based on territorial males. 2 3 . . . . . Table 3: Backwater Wetland/Stream Bank Shorebird and Wading Bird Use' . Pre- Species Canst Year 1 Year 3 Year 5 Dunlin 0 25 50 260 . Great Blue Heron 4 6 7 5 Green Heron 0 0 0 3 Killdeer 4 10 15 26 . Least Bittern 0 0 0 1 Lesser Yellowlegs 0 0 3 10 Long Billed Dowitcher 0 0 0 40 . Semi pal mated Plover 0 0 0 11 Spotted Sandpiper 0 6 6 10 . Western Sandpiper 0 0 10 200 . I . . 1 Maximum number at anyone time. . . . Table 4: Backwater Wetland/Stream Bank Waterfowl Use . Pre- Peak Use Total Const Numbers Days Broods Young Year 1 50 2,250 0 0 . Year 2 850 47,500 10 53 Year 3 1,140 63,400 16 72 Year 5 900 64,000 15 68 . . . . . . . . . . . . . . . . . - - - - - - - - - - - - - - - - Surface Water Detention Pond Nesting and/or Maximum Numbers Observed Pre-Const Year 1 Year 3 Year 5 Species Nests,'Max # Nests/Max # Nests/Max # Nests:Max # - = = - = - = - Bewick's Wren' 0 0 0 0 1 .. 2 .. Blue-winged Teal 0 0 0 0 0 6 0 0 Brewer's Blackbird 0 0 0 0 1 4 4 15 Bufflehead 0 0 0 10 0 10 0 12 Canada Goose 0 0 0 2 1 10 3 22 Cinnamon Teal 0 0 0 0 0 4 0 11 Common Snipe 0 0 0 4 0 10 2 15 Dunlln 0 0 0 25 0 20 0 40 Emperor Goose 0 0 0 0 0 2 0 0 Gadwall 0 0 0 4 1 6 0 10 Great Blue Heron 0 0 0 5 0 7 0 5 Green Heron 0 0 0 0 0 0 1 3 Green-winged Teal 0 0 0 30 2 32 3 60 Lesser Yellowlegs 0 0 0 0 0 3 0 2 Long-billed Marsh Wren 0 0 1 2 2 6 2 5 Mallard 0 0 0 40 3 25 4 30 Pintail 0 0 0 5 0 40 0 75 Red-winged Blackbird 0 0 0 2 1 4 3 10 Shoveler 0 0 0 0 0 15 2 25 Virginia Rail 0 0 0 0 2 10 3 13 Western Sandpiper 0 0 0 30 0 10 0 12 Winter Wren 0 0 1 2 3 6 3 6 Yellowthroat 0 0 1 .. 2 .. 4 15 - 1 Based on territorial males 2 No accurate count TABLE 5 .