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HomeMy WebLinkAbout3466; OLIVEHAIN RD WIDENING AND REALIGNMENT; BIOTECHNICAL LETTER REPORTS; 1998-04-28COMMUNITY PLANNING & ENVIRONMENTAL STUDIES April 28, 1998 David Bentley Colina Roble, LLC 3573 East Sunrise Drive, Suite 221 Tucson, AZ 85718 Subject: Tentative Ma for Colina Roble - CT 98-02 Dear Mr. Bentley:' This letter addresses revisions to the Tentative Map (TM) for Colina Roble - CT 98-02 made in response to comments from the City of Carlsbad (April 14, 1998). This letter is intended to serve ,S as an addendum to a letter report (dated December 1, 1997) that identified and quantified the impacts associated with this project prior to the revisions. BACKGROUND The TM proposes a 28-lot residential development with two open space lots. The site is located in the City of Carlsbad, immediately southwest of the intersection of Rancho Santa Fe Road and Olivenhain Road (Figures I and 2). The'-"cubject property is vacant with a portion of the site disced on a regular basis The areas co Lred by native vegetation support a complex mosaic of wetland habitats (freshwater marsh, '• coastal salt marsh, and southerñ.willow scrub),.coast live oak wdodland and southern mixed chaparral (Figure 3). The wetland habitats occur in the northern portion of the site, while the upland habitats occur in the southern portion. DISCUSSION . Revisions to the previous project design include the following: (1) the alignment and construction of a City of Carlsbad (City) trail segment, within the riparian buffer area to eventually connect with the proposed City of Encinitas trail system and (2) designation on the tentative map of full dedication and provisions for future grading for the widening of Rancho Santa Fe Road along the . eastern boundary of the project (see Tentative Map). In the previous analysis of impacts associated with the TM, approximately 0.28 acre of jurisdictional wetlands, as defined by the U.S. ECEVED 9903 Businesspark Avenue • San Diego, California 92131-1120 . • t, /7 bfrna@sha.cerf.net • 7 \' (619)578-8964 FAX(619)578-0573 David Bentley April 28, 1998 Page 2 Army Corps Engineers. (ACOE), would be lost. The construction of an 8-foot wide trail/path within the riparian buffer area along the north edge of lots 1-19 and south of the access street would impact an additional 0.05 acre of jurisdiction wetland for a total of 0.33 acre that will be lost to construction of the TM. Grading to widen Rancho Santa Fe Road would impact 0.41. acres of jurisdictional wetlands not previously identified (see Tentative Map). The road widening would not be constructed concurrently with the residential development, but sometime in. the future. Total project impaci to wetlands under the jurisdiction of the'ACOE totals 0.74 acre. RECOMMENDATIONS Impacts to wetlands will require a 404 Permit from the ACOE, a 401 Waiver/Certification from the Regional Water. Quality Control Board, and a Section' 1603 Streambed Alteration Agreement with the California Department of Fish and Game (CDFG). Nationwide Permit #26 issued by the ACOE for a discharge-of less than 3 acres within headwaters and isolated waters maybe used for this project. It should be noted that any impact greater than 0.33 acre requires a pre-contruction notification to the ACOE and that the current Nationwide Permit #26 expires December 13, 1998: Nationwide Permit #14, which authorizes minor discharges for road crossings, may be used for the future road widening project. 'Nationwide Permit #14 allows up to 0.33 acre and 200 linear feet of impacts and expires January 13, 2002. There is no fee associated with applications for 404 permits from the ACOE. A wetland 'delineation completed in compliance with the U.S. Army Corps of Engineers 1987 Wetland Manual must be provided with applications for either. Nationwide Permit #14 or #26. or,ueruncauon under sectlon:,4U.i Or The Uean.Water Act, by thd.RegionaVWater.Quality; ControF.. Board. An application to the Regional Water QuàlityContrbl goardniust be accompanied by a' check for $500.00. The California Department of Fish and Game requires that a Streambed Alteration Agreementbe signed by the project applicant to ensure compliance with Section 1603 of the Fish and Game,Code. The fee for this permit varies and is dependent upon the cost of the proposed project. Three area totaling 1.5'acres are available on-site for wetland mitigation: 0.4 acre found within the riparian buffer area, 0.5 acre found adjacent the eastern boundary of the property, and 0.6 acre found along the northern boundary of the property. The restoration plan would include the removal of fill (i.e., horse manure that has been dumped in the area) and non-native plant species,' David Bentley April 28, 1998 Page 3 the planting of woody glasswort (Salicornia virginica) and alkali-heath (Frankenia sauna), and the distribution of a coastal sage scrub hydroseed mix along the slope leading down to the wetlands to stabilize the bank and avoid siltation of the wetlands. In addition, the wetlands would be enhanced by the removal of tamarisk (Tamarir sp.) which is an invasive weed of aquatic habitats. Although, the road widening will be constructed. in the future, impacts to' wetland 'habitat should be mitigated at the same time as those associated with the residential development This measure would be a more cost effective mitigation schedule for the project proponent as well as beneficial to the existing wetlands If you have any questions or comments iegarding this report, please do 'not hesitate to contact me at (619) 578-8964. • Sincerely yours, O Gladys T. Baird Associate Biologist Attachments: Figure 1 Regional Location • ' Figure 2 - Site Location cc Robert C Ladwig, Ladwig Design Group, Inc ~m H. It1p onev ssai1is 0 5 10 miles Regional Location PROJECT LOCATION fton.el l:uaalzs~lcl JAN 2'" 'TY OF (.. 'tANNINC: COMMUNITY PLANNING & ENVIRONMENTAL STUDIES December 1, 1997 Mr. Robert C. Ladwig Ladwig Design Group, Inc.' 703 Palomar Airport Road, Suite 300 Carlsbad, California-92009 Subject: Wiegand Property (Ladwig Design Group, Inc. - J/N L-1039) Dear Mr. Ladwig: j This letter summarizes a revised project plan known as "D-3" and dated November 20, 1997. It also includes an impact analysis based on the new project design as well as a discussion of potential mitigation sites for project impacts. This letter is intended to serve as an addendum to the Wetland Delineation Report for the Wiegand Property (May 1997), prepared by Mooney & Associates. BACKGROUND The project proposed for this property is a 28-lot residential development with two open space lots. The site is located in the City of Carlsbad, immediately southwest of the intersection of Rancho Santa Fe Road and Olivenhain Road (Figures 1 and 2). The subject property is vacant with a portion of the site disced on a regular basis. The areas covered by native vegetation support a.cornplex mosaic of wetland habitats (freshwater, marsh, coastal salt marsh, and southern willow sLrllh) coast live oak woodland and southein InI\Ld . chaparral (Figure 3). The wetland habitats occur in the nortlem"portionof the site while the more upland habitats occur in the southern portion of the site., Field reviews of the subject property were heldon October 14, 1997 and again on November 19, 1997. In attendance were staff members from the various resource agencies as well ,as Mooney & Associates and yourself. . DISCUSSION The project design was revised after considering recommendations from the resource agencies. Revisions included: moving the grading line out of the coast live oak woodland, realigning "A" Street, adding a brow ditch in the southeastern corner of the site, and revising, the wetland limits 9903 Businesspark Avenue San Diego, California 92131-1.120 bfnia@sha.cerf.net (619) 578-8964 FAX (619) 578-0573 RECEIVED DEC. 0219!)? 1ABW1DESIN BR Robert C. Ladwig December 1, 1997 Page 2 and the grading limits adjacent to the wetlands. Implementation of the project would impact approximately 0.28 acre of jurisdictional wetlands per the U.S. Army Coprs of Engineers definition and 0.4 acre of southern mixed chaparral (Figure 4). The resource agencies have a policy of "no net loss" of wetland habitats. The loss of 0.28 acre of jurisdictional wetlands would, therefore, be considered a significant impact. Mitigation for the loss of any wetlands. woud be replacement of the habitats at a ratio commensurate with the size and quality of the habitats lost. The final mitigation ratio will be determined by the U.S. Army Corps of Engineers. The project would impact a 0.4 acre of the on-site southern mixed chaparral. The small loss would not preclude use of the remaining chaparral as a wildlife corridor. - . There is a potential for three sensitive plant species to be present in the southern mixed chaparral: the Federally Threatened and State Endangered Encinitas baccharis (Baccharis vanessae); the Federal Species of Concern summer holly (Comarostaphylis divers (folia spp. divers(folia); and the Federal Species of Concern Nuttall's scrub oak (Qüercu.s dumoswn). All three species have been reported to occur on the nearby Encinitas Ranch project, therefore, the potential for the three species to occur on the subject property is. moderate to high. A directed survey would be needed to confirm their presence or absence prior to clearing and grubbing of the site. Any impacts to. the Encinitas bãccharis would be considered a significant impact. Avoidance of any impacts to the Encinitas baccharis is preferred. If impacts cannot be avoided, then the resource agencies should be consulted for the appropriate mitigation measures. Approximately 6 acres of summerholly and Nuttall's scrub oak habitat (chaparral) will be preserved in an open space lot, therefore, any potential losses of the two species in-the 0.4 acre,ofchaparral impacted would not .• be considered a significant impact Five sensitive bird species have been reported to occur within thevicinity of the project site: the State and Federally-listed Endangered southwestern willow flycatcher (Empidonax trailii extimus) and least Bell's vireo (Vireo bellil pusillus);. the State Species Of Concern yellow-breasted chat (icteria virens) and yellow warbler (Dendroicã petechiO); and the locally declining downy woodpecker (Picóides pubescens). All of these species are associated with southern willow scrub The potential for these five species to occur in the on-site habitat, however, is very low due to the small size of the southern willow scrub. RECOMMENDATIONS Two areas totaling 1.1 acres are available on-site for wetland restoration: 0.6 acre located between the toe of the slope of .the developed area and the limits of the wetlands and 0.5 acre located S Robert C. Ladwig December 1, 1997 Page . r adjacent the eastern boundary of the property. The restoration plan would include the removal of fill (i.e., horse manure that has been dumped in the area) and. non-native plant species and the planting of woody glasswort (Salicornia vzrgin:ca) and alkali-heath (Frankenia sauna) In addition, a coastal sage scrub hydroseed mix is recommended for the slope leading down to the wetlands. This measure would stabilize the bank and avoid siltation into the wetlands. A directed survey for the Encinitas baccharis is recommended after the limits of construction are flagged. - Although the sensitive bird species described above have a very low potential to occur on- the site, any construction work, such as clearing and-grubbing, should be avoided during. the breeding season (February 15 through August 30). If developnient is proposed during the breeding. period, a directed survey shall be conducted to confirm the presence or absence of breeding birds. Protective measures shall be implemented to avert potential disruption of the breeding behaviour of all-birds that ma be present. - If you have any questions or comments regarding this report, please do not hesitate to contact me - - at (619) 578-8964. - - - -. cc: David M. Bentley - - - Real Estate Investment & Development - 3573 E. Sunrise Drive, Suite 221. Tucson, AZ 85718, - - COMMUNITY PLANNING & ENVIRONMENTAL STUDIES May 8, 1997 Mr. Robert C. Ladwig Ladwig Design Group, Inc. - 703 Palomar Airport Road, Suite 300 Carlsbad, California 92009 Subject: Wiegand Property in the City of Carlsbad (Ladwig Design Group, Inc. - JIN L-1039) Dear Mr. Ladwig: RECElVE: A1 L CITY u CAFLSBAD PLANNING DEPT. fl This letter reports on a preliminary review of the general biology and wetlands at the southern edge of Encinitas Creek. INTRODUCTION The review of the site focused on mapping the vegetation communities on the property and the identification of biological constraints to developing the property. The site is located in the City of Carlsbad, immediately southwest of the intersection of Ranchô Santa Fe Road and Olivenhain Road (Figures 1 and 2). The northern portion of the site is fairly flat with the elevation approximately 100 feetabove sea !e.vCl ( rising to approximately 210 feet ASL at the southern boundary of the.site. ASL) and Two box culverts were observed along the eastern boundary of the property. Water was flowing from the culverts to the west. . The subject property is vacant with a portion of the site disced on what appears to be a regular basis. The surrounding land uses include a residential development to the south; a residential development and an equestrian facility to the west; a maintenance yard for Olivenhain Municipal Water District and a feed and tack shop to the north; and Rancho Santa Fe Road and a pasture for cattle beyond it to the east. R ELCEMED . L - 9903 Businesspark Avenue r r I\I C San Diego, California 92131-1120 bfma@sba.cerf.net (619)578-8964 FAX(619)578-0573 . - ' Mr Robert C Ladwig May 8, 1997 Page METHODS A field assessment of the site was conducted on April 24, 1997, by Lisa Embree and Gladys Baird between the hours of-0745 and 1245. The weather at the beginning of the survey was cool with temperatures in the low to mid 60's, overcast skies and a slight breeze. At the end of the survey, the temperature was in the low to mid 70's, clear skies, and a stronger breeze. Resources were mapped on a 1 inch = 100 foot scale aerial map. Photo documentation of the site was taken. A wetland delineation was performed on the south side of the Encinitas Creek concurrently with the general biological survey. Existing conditions were observed and indicators of wetland vegetation, hydric soils and wetland hydrology were noted on standard Army Corps of Engineers (ACOE) routine delineation data forms for five test plots. Boundaries of wetlands were drawn on the 1 inch. = 100 foot scale aerial used for the general survey. .. . . . . The Environmental Impact Report and Biological Survey and Report for the Olivenhain Road Widening/Realignment and Flood/Control Project prepared byMooney & Associates (formerly Brian F.. Mooney Associates) in 1991 was reviewed for this report. . . RESULTS The ptóject area supports a complex mosaic of wetland habitats (freshwater marsh, coastal salt marsh, and southern willow scrub)-as well as upland habitats (disturbed; southern mixed chaparral and coast live oak woodland) (Figure 3) The wetland habitats occur in the northern portion of the site while the more upland habitats occur in the southern portion at The fresh marsh is dominated by soft flag (lypha latfolia) with other species observed including salt marsh fleabane (Pluchea odorata -var.,: odorata) and southwestern spiny rush Juncusacutus var. leopoldii) The coastal salt marsh is the dominant type of wetland habitat on the site This habitat is dominated by woody glasswort (Salicornia virgin/ca) with Other species present including alkali-heath (Frankenia sal/na) and alkali mallow (Mai'e1la leprosa). Also present were a few dried or almost dried salt beds scattered among the plants. . Southern willow scrub occurs in scattered locations. The dominant overstory species was arroyo willow (Salix lasiokpis) with an understory of mulefat (Baccharis salic?folia) and western ragweed (Anzbrosicipsilosiachya) and narrow-leaved willow (S. exigua) also occur in isolated stands in the freshwater marsh area as well as in the chaparral in the southeastern corner of the site. I Mr. Robert C. Ladwig May 8, 1997 Page 3 Disturbed habitat occurs in the middle of the site as well as along the eastern margin adjacent to the Rancho Santa Fe Road right-of-way. The middle of the site appears to be disced on an annual basis. The vegetation in this 'area consists of ruderal species such as mustard (Brassica sp.), bromes (Bronms spp.), Indian sweet clover (Mel/lotus indicits) and white stem filaree Erodium rnoschatuni). One very large, old coast live oak (Qitercus agrfolia) was located in the western end of this area. Crown daisy (Chiysanthemuni coronariurn) was the dominant species along.the roadway with other species present including mustard, wild oats and hottentot fig (Carpobrotus edulis). Coast live oak woodland, dominated by coast live oak, occurs in the southwestern corner of the site. The understory was dense and undisturbed with species including poison oak (Toxicodendron diversiloba), toyon (Heteronieles arbiit(folia), honeysuckle (Lonicera siibspicata), California sagebrush (Artensisia calfornica), and black sage (Salvia niel/?fera). Southern mixed chaparral occurs in the southeastern corner of the site. In 'portions of the chaparral, scrub Oak (Quercus berberid(folia) is the dominant species and in other' areas chamise Adenostoma fasviczilatuni) is the dominant species. Other species observed in the chaparral include monkeyflower (Mirnulus aurantiacus), black sage, California sagebrush and flat-top buckwheat (Eriogonum fasciculatum). A small portion of the chaparral along the shoulder of Rancho Santa Fe Road has been disturbed by clearing but is returning. DISCUSSION Development is proposed for the subject property. The wetland habitats and coast live oak woodland are considered sensitive habitats due to their loss to development. In addition, wetlands are. subject to regulation by the U.S. Army Corps of Engineers (ACOE) pursuant to Section 404 of the Clean' Water Act, the California Department of Fish and Game (CDFG) pursuant to Section 1603 of the CDFG code requiring a Streambed Alteration Agreement, and 'the California Regional Water Quality Board requiring a Section 401 Water Quality Certification. A buffer of50feetfrom'the'interface between the wetland habitats and the proposed development should be incorporated into the project design. Mitigation for the loss of any wetland would be replacement of the habitats lost at a 2:1 ratio due to the size and quality of wetland habitat lost and its relationship to similar habitat on adjoining lands. One sensitive plant. was observed in the wetlands, southwestern spiny rush (Figure 3). However, no impacts to this species is anticipated due to proposed protection of the wetlands. The coast live oak woodland on the site is relatively undisturbed. A buffer of 50 feet from the edge of the woodland canopy should be included in the project design. Any losses incurred would require mitigation at a 3:1 ratio for the canopy area lost and mitigation for the loss of individual oaks would be replacement at 10:1 ratio. Mitigation may include revegetation on-site or purchase of credit in an oak woodland mitigation bank. Mr. Robert C. Ladwig May 8, 1997 Page Historically, southern mixed chaparral has not been considered a sensitive habitat unless sensitive resources are present or the chaparral is part of a wildlife corridor of native habitat. There is a potential for three sensitive plant species to be present in the chaparral: the Federally Threatened and State Endangered, Encinitas baccharis (Baccharis vanessae); the Federal Species of Concern, summer holly (Cornarosiaphylis diversfo1ia ssp. divers?folia); and: the Federal Species of Concern, Nuttall's scrub oak (Quercus dumoszirn). Directed surveys would be needed to confirm their presence or absence'. Regardless of the presence or absence of sensitive species in the chaparral, the regulatory agencies have been taking a stronger look at chaparral habitat primarily due to the State-mandated Natural Community conservation Planning Program (NCCP). The NCCP provides protection and perpetuation of natural wildlife diversity on a regional basis while allowing compatible land use and appropriate development. The agencies will likely consider the chaparral on-site a component of a wildlife corridor, albeit a small one. A 50 foot setbick is recommended to preserve the chaparral habitat. The Wild/Urban Interface Fuel Modification Standards (San Diego County Wildland/Urban Interface Task. Force 1995) established the need to provide, in high and very high fire ha.zard areas such as chaparral habitat,. a 50 foot, irrigated zone. Guidelines require that all combustible material be removed within the zone and replaced with drought-tolerant, fire resistant plants to reduce the level of risk to an acceptable level. If the fuel modification zone extends into the chaparral habitat, the impacts would need to be addressed. - The biological study completed in 1991 (Mooney 199 1) reported the potential for several sensitive plant species to occur on the site: Del Mar sand aster which is listed as CNPS List lB (Corethrogyne filaginfolia var. linfolia. A sand aster was observed in 1991 west of the tack shop rear the northeastern corner of the site, however thL timing of that survey precluded duLrmlnln~fjt w sensiti'e Del Mar sand aster Two sensitive bird species were observed during the 1.991 study: downy woodpecker (Picoides pubescens) and southwestern willow flycatcher (Enipidonax trailii extinnis). The downy woodpecker is considered declining by Everett (1979) while the flycatcher is a State and Federally Endangered species and is considered sensitive by several special interest groups. These species were observed in southern willow scrub habitat near the intersection of Olivenhain Road and El Camino Real. ) Other riparian bird species reported to potentially occur in the area are the yellow warbler (Dendroica petechia), the yellow-breasted chat (Icleria virens) and the least Bell's vireo ( Vireo bellii pusillus). The yellow warbler and yellow-breasted chat are State Species of Concern while the least Bell's vireo is a Federal and State listed Endangered species. and a Species of Concern by Everett (1979). The Mr. Robert C. Ladwig May 8, 1997 Page 5 small size of the on-site habitat precludes these three species as well as the downy woodpecker and the southwestern willow flycatcher from potentially occurring on the subject property. It is unlikely the site provides habitat for any other listed bird species, however, an updated Natural Diversity Data Base Search would need to be conducted to adequately determine other species potentially occurring on the site. Although the sensitive bird species described above are not likely to occur on the site, any construction work, such as clearing and grubbing, should be avoided during the breeding season (February 15 through August 30) to eliminate potential disruption of breeding behavior of all breeding birds. The project site is within the City of Carlsbad's (City) Multiple Habitat Conservation Program, a subregional plan for the State-mandated NCCP. Early dialogue with the City in developing construction plans would facilitate permitting for the property in accordance with the City's conservation program. If you have any questions or comments regarding this report, please don't hesitate to contact me at (619) 578-8964. Sincerely yours, 4/x Lisa Embree Senior. Biologist . . . . LE:gb . . . cc: David M. Bentley, CCIM Real Estate Investment & Development 3573 E. Sunrise Drive, Suite 221 Tucson, AZ 85718