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Home My WebLink AboutCT 94-01; Poinsettia Shores; Tentative Map (CT) (26)DEK& ASSOC tf 19) 94514? Brian J. Murphy Kaiza Poinsettia Corporation 7220 Avenida Encinas Suite 200 Carlsbad, California 92009 Subject: Biological survey of proposed destitution basins for Kaiza Project, City of Carlsbad, San Diego County, California, Dear Mr. Murphy: The purpose of this letter is to present the findings of a reconnaissance-level survey conducted by Dudek &. Associates, Inc., biologist John W. Brown, Ph.D., of two alternative sites for proposed desiltation basins in the area north of Batiquitos Lagoon, City of Carlsbad, San Diego County, California (Figures 1 and 2), in association with the Kaiza project. The survey consisted of thoroughly walking through and around each location that would be affected by construction, as well as an area approximately 100 feet outside the footprint of construction. Dr. Brown mapped plant communities and noted sensitive species and estimated their population numbers where present. The surveys were done in a manner adequate to respond to the issues articulated in our proposed scope of work including: 1) Determination of existing conditions at each site. 2) Determination of potential direct impacts at each site. 3) Determination of whether significant impacts per CEQA would occur at either site. 4) Comparison of biological impacts of the two sites. 5) A discussion of conceptual mitigation for each site. 6) Identification of the resource agency reviews and approvals that would be necessary for desiltation basin construction. EASTERN SITE The proposed eastern site (Figure 3) represents an existing desiltation basin that is contiguous with a narrow finger of riparian habitat extending northward from the northern edge of Batiquitos Lagoon. The area potentially affected by construction of a new basin would include 0,10 acre of southern willow scrub, 0.31 acre of coastal and valley freshwater marsh, 0.22 acre of coastal sage scrub, 0.02 acre of ornamental landscaping, and 0.30 acre of disturbed habitat. including a broad concrete drainage. The southern willow scrub habitat consists of several willow trees '(Salix sp.) in the bottom of the drainage. The freshwater marsh is dominated by a dense stand of cattail (Typha sp.) and bulrush (Scirpus sp.). Coastal sage scrub surrounding the drainage is dominated by California bush sunflower (Encelia California), with exceedingly few individuals of deerweed (Lotus scoparius) and flat-top buckwheat (Eriogonitm fasciculatum). The ornamental landscaping is A e._. .b' C, a 2 Hr9T0Z£9 6T9 c oW WBrian Murphy 3 May 1994 Desiltation Basins page 2 part of a linear band of myoporum (Myoporum laetwri). The disturbed habitat includes bare ground, an earthen berm, a concrete drainage channel, and ruderal areas dominated by black mustard (Brassica nigra). Wildlife species observed at the eastern site include California ground squirrel (Spermophilus beecheyi)> cottontail rabbit (Sylvilagus sp.), red-winged blackbird (Agelaius phoeniceus), and swallow (Hirundo sp.). No sensitive plant or animal species were observed. Sensitive animals potentially present include the federally-listed threatened California gnatcatcher (Polioptila californica), tricolored blackbird (Agelaius tricolor), and light-footed clapper rail (Rallus hngirostris levipes). Impacts to coastal and valley freshwater marsh, southern willow scrub, and coastal sage scrub would be considered significant per the California Environmental Quality Act (CEQA) and would require mitigation in the form of revegetation or offsite purchase of habitat, coupled with its dedication to open space. Impacts to wetland habitat are likely to require a California Fish and Game Code Section 1603 Streambed Alteration Agreement. Impacts to coastal sage scrub would require coordination with the City of Carlsbad and consistency with the current 4(d) rule as regulated by the U.S. Fish and Wildlife Service. Prior to any disturbance of the existing habitat, a wetland delineation would be required by the U.S. Army Corps of Engineers. Also, it is likely that the California Department of Fish and Game (CDFG) and/or the U.S. Fish and Wildlife Service would require focused surveys for the gnatcatcher and clapper rail prior to any construction activities. Although neither is likely to be present, if they are found to be resident onsite, accommodating either of these species would require considerable consultation with the resource agencies, additional mitigation, and scheduling of construction activities to avoid their breeding and nesting seasons. WESTERN SITE The proposed western basin site (Figure 4) represents highly disturbed habitat an a small area of coastal sage scrub just east of Highway 101 at the northwestern corner of Batiquitos Lagoon. The area potentially affected by construction of a new basin would include 0.18 acre of coastal sage scrub and 1.15 acres of disturbed habitat. The coastal sage scrub is mostly disturbed, consisting of a slope dominated by saltbush (Atriplex canescens), and a level area at the foot of the slope with California bush sunflower, bladder-pod (Cleome isomeris), and California sagebrush (Artemisia californica). The disturbed habitat is a highly saline flat that appears to represent an historical fill area. It has a ground cover of sea-fig (Carpobronis edulis), with scattered individuals of coast goldenbush (Jsocoma menziesif), everlasting (Gnaphalium palustre), and deerweed, and small patches of dot-seed plantain (Plantago erecta} and alkali weed (Cressa truxillensis). 6/G'd S31bI30SSU "8 >Gdna Wb33:TI fr-6, 8 :t>6308£t76T9 <-t?9I02£9 6T9 '• W«92:TT b6-£ -9 '. 0T0i T t>6-£ -G ' 0T0i Brian Murphy 3 May 1994 Desiltation Basins paae 3 Wildlife species observed at the western site include Idlldeer (Charadrius voti/ems) and coast western whiptail lizard (Cnemidophonts tigris). Sensitive wildlife species potentially present include the federally-listed threatened western snowy plover (Charadrius alexandrmus) and California gnatcatcher. One sensitive plant species, southwestern spiny rush (Juncus acutiis ssp. leopoldii), is present; the population consists of about 70-80 individuals. This species is listed by the California Native Plant Society as a "List 4" species. List 4 species have the lowest level of sensitivity. It is likely that the California Department of Fish and Game (CDFG) and/or the U.S. Fish and Wildlife Service would require focused surveys for the gnatcatcher and snowy plover prior to any construction activities. Although neither is likely to be present, if they axe found to be resident onsite, accommodating either of these species would require consultation with the resource agencies, some form of mitigation, and scheduling of construction activities to avoid their breeding and nesting seasons. Because of the close proximity of the newly established least tern nesting area, construction activities would have to be scheduled to avoid nesting and breeding season of this species. It is possible that the proposed desiltation basin would provide habitat for predators that may affect nesting least terns. If the resource agencies reach this conclusion, a predator trapping program may be required as a regular maintenance activity. Alternatively, the dense wire mesh fencing currently in place around the least tern nesting area may effectively inhibit encroachment by predators. The primary biological constraints on the western site are the 0.18 acre of coastal sage scrub and the small population of southwestern spiny rush. Impacts to the rush could be mitigated by salvaging and transplanting the individuals potentially affected by construction. SUMMARY AND CONCLUSIONS Disturbance to wetlands, including deposition of fill or removal of vegetation, is regulated by Section 1603 of the California Fish and Game Code (administered by the California Department of Fish and Game). Discharge of dredge or fill material in wetlands or waters of the United States is regulated by Section 404 of the Clean Water Act (administered by the U.S. Army Corps of Engineers). Existing wetland habitat on the eastern site would be regulated by the 1603 process, however, in the absence of a federal jurisdictional wetland delineation, we are not certain that it would be regulated by the Corps under 404. The California Department of Fish and Game essentially has no minimum acreage that they regulate, whereas the Corps provides the Nationwide Permit for fills under one acre, providing all other conditions of the Nationwide Permit are met (including the requirement that there are no adverse impacts to listed threatened or endangered species). Because no wetland habitat is present on the western site, there would be no need for the involvement of the Corps or the California Department of Fish and Game. Disturbance of upland habitat may be regulated by the Migratory Bird Treaty Act, which stipulates that no take of migratory birds shall occur. Effectively, this means that no nesting birds could be affected. This can be accommodated by scheduling construction 6/fd SllblDOSSb "8 »3dna Wb82:TT f6, £0 AUW 6T9 '• WbiE:TU fr6-£ -S c o Brian Murphy 3 May 1994 Desiltation Basins Dace 4 activities to avoid the nesting season of local native bird species. Because the eastern site currently supports considerably more native habitat, including wetlands, it is a more constrained site. It is likely that project implementation on the eastern site would require greater permitting and coordinating activities. The western site is virtually constraint-free, with the exception of the small, disturbed patch of coastal sage scrub (0. 1 8 acre). However, it is likely that some form of mitigation may be required for impacts to southwestern spiny rush, and construction activities may need to be scheduled to avoid least tern breeding and nesting season. Project implementation on the western site actually results in a net benefit to biological resources - an acre of wetland habitat is created from a highly disturbed area dominated by sea-fig (ice-plant). If you have any questions regarding this report, please call me or John W. Brown, Ph.D., at (619) 942-5147. Very truly yours, .OLD A. WIER gical Sciences Manager cc: Eric Munoz, City of Carlsbad siibiDOSsb s >aana wyssai *?s/ £0 AUN «-t>9T0Z£9 6T9 f W«8E:TT f6-£ -9 . San Diego ASSOCIATION OF GOX'ERXME.NTS Biological Survey for Proposed Desiltation Basins - Kaiza Project, City of Carlsbad Regional Map 6/9-d 6T9 "8 >oana -S I 0T0i , £0 Q . «I1V V.*'?- .'V .- -.^f ydv-sj; Jft*&£& L<A*G'*001'IQUlTOS Acgsj'-^i- ^"wi SOURCE: U6SG 7.5 Minute Series, Encinltas Quadrangle 1" - 2000' Biological Survey for Proposed Oesiltation Basins • Kaiza Project City of Carlsbad Vicinity Map 9 6/i'd L tt rf 6908£t?6T9 6T9 S3i«ioossy T f6-£ -S Habitat Types: CSS I Coastal Sage Scrub—»«^j SWSi Southern Willow Scrub^MHKJ FWM[ Freshwater Marsh DfT] Disturbed Habitat OP I Ornameatai Plantings Biological Survey for Proposed Desiltation Basins - Kaiza Project, City of Carlsbad Biological Resources Map * Eastern Site 6/8 'd 8 8:6T9 >aana wbi£:TT t?6, £0 S : Propo&d Limits of Grading: Habitat Types: f" •»I CSS I Coastal Sage Scrub DH I Disturbed Habitat r - ICQ' :-i Biological Survey for Proposed Desiltation Basins • Kaiza Project, City of Carlsbad Biological Resources Map • Western Site FIGURS 4 6/6 'd 6T9 >aana -£ -S .' , ee AWU