Riparian Restoration Plan for the. San Lorenzo Valley Water District s. Campus Development Project

Transcription

1 Riparian Restoration Plan for the San Lorenzo Valley Water District s Campus Development Project Prepared by Jodi M. McGraw, Ph.D. Jodi McGraw Consulting PO Box 221 Freedom, CA (831) jodi@jodimcgrawconsulting.com Prepared for Jim Mueller District Manager The San Lorenzo Valley Water District Highway 9 Boulder Creek, CA Submitted to County of Santa Cruz Planning Department 701 Ocean Street Santa Cruz, CA January 3, 2012

2 Table of Contents List of Tables List of Figures Executive Summary iii iii iv 1 Introduction The Project Project Site Location Land Use and Ownership Environmental Conditions 2 2 Restoration Restoration Site Restoration Goal and Objectives Restoration Tasks Phase 1: Project Construction Phase 2: Invasive Plant Eradication Phase 3: Native Plant Revegetation Phase 4: Restoration Maintenance 12 3 Adaptive Management and Monitoring Plan Success Criteria Monitoring Qualitative Site Assessment Quantitative Assessment of Success Criteria Status Adaptive Management Reporting 15 4 Plan Implementation Anticipated Project Schedule Annual Implementation Schedule Personnel Funding 17 References 18 Appendix A: Riparian Buffer Area (Lewis 2011a) 19 Appendix B: Landscape Planting Plan (Lewis 2011b) 20 Jodi McGraw Consulting (JMc) ii January 2012

3 List of Tables Table 1: Plant species observed in or adjacent to the riparian restoration area. 5 Table 2: Restoration objectives and tasks for each of four phases of the project. 8 Table 3: Anticipated schedule for phases of the restoration project 16 List of Figures Figure 1: Restoration site within the San Lorenzo Valley Water District s Campus Development Site 3 Jodi McGraw Consulting (JMc) iii January 2012

4 Executive Summary This document describes tasks that will be conducted as part of a five-year plan to restore habitat within an approximately 0.15-acre area adjacent to the San Lorenzo Valley Water District s new campus site, which is located at and Highway 9 in Boulder Creek, California (APNs: , -03, -04, -06, and -07). The restoration plan is a component of the District s application for a development permit to construct a new campus at the 1.7-acre site. Development of the new facility will permanently impact approximately 975 square feet within a riparian buffer area: the area located within 50 feet and 30 feet, respectively, of the perennial and ephemeral reaches of an anthropogenic drainage located on the east side of the property (Lewis 2011a; Appendix A). This area, which the County determined meets the criteria for protection under the Riparian Corridor and Wetland s Protection Ordinance, is highly degraded as a result of prior land use and invasion and spread of non-native plant species including Himalayan blackberry (Rubus armeniacus). The goal of this restoration is to enhance the native plant cover, species richness, and natural functions, including soil stabilization and provision of animal habitat, of the 0.15-acre area surrounding the drainage ditch east of the property. This goal will be attained through work toward four primary objectives: 1. Protect native plants and the hydrologic function on site during development and exotic plant control, so that native plants established within the site can promote restoration; 2. Control or eradicate, where feasible, invasive plants that outcompete native plants and degraded habitat by native animals (Section ); 3. Establish native plant species to create the natural community structure and species composition of a creekside community, using plants salvaged from the site and other local sources; and 4. Maintain and promote growth and regeneration of an assemblage of native plants typical of a seasonal drainage within the coast redwood forest, to provide habitat, stabilize soil, and promote hydrologic functions. Each objective represents a phase of the restoration project, within which a series of tasks have been identified to attain the objectives. Summarized in Table 2, key components of the phases include: 1. Phase 1-Project Construction (Year 1): Salvage native species within the limits of grading, and mark native plants and fence the drainage to prevent impacts to native species left on site; 2. Phase 2-Invasive Plant Eradication (Years 1-2): Remove Himalayan blackberry, English ivy (Hedera helix), French broom (Genista monspessulana), and silver wattle (Acacia dealbata) using manual techniques designed to limit their re-growth; 3. Phase 3-Native Plant Revegetation (Years 2-3): Develop a detailed revegetation plan based on the site conditions examined following invasive plant eradication, and then install native shrubs and herbs propagated from on-site or other local sources, to create layered vegetation typical of natural riparian communities; and 4. Phase 4-Restoration Maintenance (Years 3-5): Control invasive plants by re-treating those that re-establish following initial treatment, and eliminating new species that may become Jodi McGraw Consulting (JMc) iv January 2012

5 established, replanting native plants as necessary, and otherwise addressing factors that could limit native plant establishment, growth, and survival. This restoration plan will be implemented through an adaptive management framework, which includes success criteria that identify the target conditions for the site, which can be evaluated through implementation of monitoring protocols. The success criteria are: 1. Total absolute native plant cover averaging at least 70%. 2. Native plant species richness (number of species) of at least 4/m 2 (alpha richness) and 18 species total (gamma richness). 3. Total absolute cover of exotic plants averaging less than 10%. 4. No significant impairments to the hydrologic functions of the ditch (e.g. soil erosion, deterioration of the channel) that would affect water quality of the ability of the site to support native plant species. Monitoring will be conducted through two complementary approaches: 1. Qualitative Site Assessments: Quarterly assessments of overall site conditions to identify the need for management during the year; and 2. Quantitative Assessment of Success Criteria Status: Annual monitoring to inform the subsequent year s management and ultimately assess success of the restoration. The plan will be implemented over a five-year period, beginning just prior to initiation of construction of the campus. Implementation will follow an annual cycle that includes: 1. Annual reports provided to the County of Santa Cruz Planning Department, that document work conducted and results of monitoring during the prior year; and, 2. Annual work plans that identify the specific tasks that will be completed during the year, based on the plan and the existing site conditions and prior year s monitoring report (if available), and a budget and timeline for their completion. The restoration plan will be implemented by the District, which will contract with a biologist with experience in the ecology and restoration who can implement the plan tasks with the assistance of technicians with experience in exotic plant control and revegetation. Each year, the District will submit a copy of the annual work plan to the County of Santa Cruz Planning Department, along with a letter indicating the intention to fund its implementation. Jodi McGraw Consulting (JMc) v January 2012

6 1 Introduction 1.1 The Project To improve the efficiency of their operations, the San Lorenzo Valley Water District (District) is seeking to develop a new campus in Boulder Creek, California that will consolidate activities currently conducted at three locations: Administration Offices located at Highway 9, Boulder Creek CA Operations offices located at Highway 9, Boulder Creek, CA; and Storage located at 101 Quail Hollow Road in Felton, CA Development of the new campus includes several component projects (inset box). As part of the Development Permit Application for the new campus, the County of Santa Cruz Planning Department requested that the District submit a restoration plan that, when implemented, will mitigate the impacts of the development on an approximately 975-square-foot (0.02 acre) portion of the project site that was determined by the County to meet the criteria for protection under the County s Riparian Corridor and Wetland s Protection Ordinance. San Lorenzo Valley Water District Campus Development Project Components (DDA 2011) Consolidating the five parcels that comprise the site Demolition and removal of two existing storage buildings Grading of 700 cubic yards of cut and 2,500 cubic yards of fill Remodel of an existing commercial building Construction of a new operations building Installation of a fueling area Installation of an on-site wastewater system, which would replace existing septic systems Installation of driveways and parking areas Installation of landscaping throughout the site The area that will be affected, which will be covered with a portion of the District s proposed operations building, is within 50 feet of an approximately 175-foot long perennial reach of a drainage ditch located largely within the county right of way east of the proposed project (Section ; Appendix A). The 30- foot buffer on the northern approximately 160-foot long ephemeral reach will not be affected (Appendix A). The area adjacent to the ditch has been modified by prior land use activities, including grading, development, and materials storage (Section 1.2.2), and features degraded habitat dominated by invasive plant species including Himalayan blackberry (Rubus armeniacus; Section ). To mitigate loss of the 0.02-acre portion of the riparian buffer, a 0.15-acre area that is located within 15 feet to the west of the drainage and five feet to the east, will be restored as part of this plan (Figure 1; Appendix A). The remaining 0.17-acres between the restoration site and building will be landscaped using native plant species to create a buffer between the restoration site and development area (Appendix B). Jodi McGraw Consulting (JMc) 1 January 2012

7 1.2 Project Site Location The proposed campus site is an approximately 1.7-acre area on the east side of Highway 9, south of Mountain Street, north of Flat Street, and east of the right of way along East Street in the town of Boulder Creek, an unincorporated area in central Santa Cruz County (Figure 1). It includes five parcels with assessors parcels numbers (APNs) of , -03, -04, -06, and -07. The two developed parcels that front Highway 9 are located at Highway 9 ( ) and Highway 9 ( ) in Boulder Creek, California The entire site is located in the southwestern quarter of Section 30, of Range 2W in Township 9S of the Diablo Base and Meridian. Of the 1.7-acre site, 0.21 acres is located within the riparian buffer area: the area within 50 feet of the perennial drainage, and 30 feet of the ephemeral drainage (Lewis 2011a; Appendix A). The restoration site is the 0.15-acre area surrounding the 235-foot long drainage located on the eastern border of the project parcels, largely within the county right of way on the alignment of East Street (Figure 1) Land Use and Ownership The project parcels are owned by the District, which purchased them in December 2005 as the site for their future campus. The western portion of the site was developed in the 1970s and includes a threestory office building ( ), which is currently used by the District and its single tenant, two storage buildings ( ) used by the District, and adjacent parking areas. The three undeveloped parcels set back from Highway 9 are not currently used, though have historically been used for parking and storage of building materials. Surrounding land use varies and includes primarily single family residences lining the side streets and interspersed between commercial uses along Highway 9, which include a fast-food restaurant north of the project site Environmental Conditions Topography The site is within the relatively broad, flat portion of the San Lorenzo River Valley, on a terrace above the San Lorenzo River. It slopes gently eastward (5-10%) toward the river, and features some limited terracing as a result of historic land use on the western portion, which including leveling the building site and parking areas (Baudry Engineering Inc. 2007) Geology and Soils The site is located on quaternary alluvium (Brabb 1989) and primarily features Ben Lomond sandy loam, a deep, coarse-loamy, well-drained soil formed in material weathered from sandstone or granitic rocks (USDA 1980). Test borings revealed the occurrence of artificial fill a depth of feet, and groundwater at a variety of depths including at existing grade (Baldry Engineering, Inc. 2007). Prior land use including the introduction of non-native fill material, grading to level the site and create the drainage ditch, and parking within the right of way, have altered the soil composition and increased the density (i.e. compacted the soil). Jodi McGraw Consulting (JMc) 2 January 2012

8 Figure 1: Restoration site within the San Lorenzo Valley Water District s Campus Development Location, Boulder Creek, California. Jodi McGraw Consulting (JMc) 3 January 2012

9 Climate The site features a Mediterranean climate with cool wet winters and warm, dry summers. Boulder Creek receives an average of 50 inches of rainfall per year, most of which falls between October and May and is concentrated between December and March. Mean maximum temperatures in July are 82.4 :F and mean minimum temperatures in January are 28 :F (PRISM Climate Group 2011) Hydrology The site is located within the Mid-San Lorenzo Watershed, a subwatershed of the San Lorenzo River located just south (downstream) of Boulder and Bear creeks: two major tributaries that flow into the San Lorenzo River in Boulder Creek. The project site is on an elevated stream terrace approximately 300 feet west of the San Lorenzo River. Due to the presence of springs, soils in the project site are saturated and inundated during the wet season (Baudry Engineering, Inc. 2007). To drain the site and adjacent wet areas, ditches have been excavated within the property. These drainages flow to ditches along Flat Street, the southern boundary, and the East Street alignment (i.e. County right of way) on the eastern property boundary (DDA 2011). The eastern ditch, which is the subject of the restoration outlined in this plan, is approximately 3.5 feet deep, and features a 2.5 foot tall berm. It conveys water from the northeastern portion of the project site to its confluence with the Flat Street ditch just southeast of the project site, where flow is then culverted under the road and discharged into the San Lorenzo River. The initial approximately 150 feet of the drainage ditch is ephemeral, featuring water during the wet season and for a short period after (e.g. October to May). The southern approximately 175 feet of the drainage features water throughout the year, and was classified as perennial (Silvernail 2010). Development of the campus is unlikely to alter the hydrology of the eastern ditch or affect its ability to support riparian plant species. Drains installed under the buildings are not anticipated to significantly reduce inputs into the drainage ditch because: 1. The building footprints and thus drainage area constitute a very small portion of the watershed that flows into the eastern drainage ditch; and 2. The drainage ditch is located downslope of the buildings, such that subsurface water will continue to flow below the drains and into the eastern ditch (R. Cahill pers. comm. 2011) Vegetation Vegetation within and near the restoration site consists of a mix of native and non-native species which reflect the sites hydrology and historical land use (Table 1). Trees include coast redwood (Sequoia sempervirens) and California bay laurel (Umbellularia californica), with planted specimens of walnut (Juglans regia and J. californica) on the perimeter. The understory is dominated by the invasive vine Himalayan blackberry (Rubus armeniacus), while the northeastern parcel features dense infestations of silver wattle (Acacia dealbata) and French broom (Genista monspessulana). Away from the dense cover of invasive plants, the restoration site features scattered occurrences of native and non-native herbs (Table 1). These include several species adapted to the moisture in and around the drainage ditch including horsetail (Equisetum telmateia), sedge (Carex spp.), rushes (Juncus patens and J. effusus) Jodi McGraw Consulting (JMc) 4 January 2012

10 Table 1: Plant species observed in or adjacent to the riparian restoration area. Scientific Name Common Name Type Origin Acacia dealbata silver wattle tree Invasive Allium triquetrum triangle onion herb Non-Native Arum italicum cuckoo-pint herb Non-Native Camellia sp. camellia shrub Non-Native Carex spp. sedge herb native Carex cf. harfordii Harford's sedge herb Native Cirsium vulgare bull thistle herb Non-Native Cyperus eragrostis tall flatsedge herb Native Equisetum telmateia ssp. braunii giant horsetail herb Native Fragaria vesca wood strawberry herb Native Genista monspessulana French broom shrub Invasive Geranium robertianum Robert's geranium herb Non-Native Hedera helix English ivy vine Invasive Holcus lanatus velvet grass grass Invasive Hypericum perforatum Klamathweed herb Non-Native Iris foetidissima stinking iris herb Non-Native Juglans cf. californica black walnut tree Native Juglans regia English walnut tree Non-Native Juncus effusus bog-rush herb Native Juncus effusus var. pacificus Pacific bog-rush herb Native Juncus patens common rush herb Native Ligustrum sp. privot shrub Non-Native Lonicera hispidula var. vacillans hairy honeysuckle vine Native Melissa officinalis lemon balm herb Non-Native Myosotis latifolia forget-me-not herb Invasive Plantago major common plantain herb Non-Native Prosartes hookeri Hooker's fairy bells herb Native Prunus cerasifera cherry plum, myrobalan shrub Non-Native Quercus parvula var. shrevei shreve oak tree Native Rubus armeniacus Himalayan blackberry vine Invasive Rumex acetosella sheep sorrel herb Non-Native Rumex crispus curly dock herb Invasive Sequoia sempervirens redwood tree Native Taraxacum officinale dandelion herb Non-Native Trifolium repens white clover herb Non-Native Umbellularia californica California bay laurel tree Native Viola cf. odorata English violet herb Non-Native Jodi McGraw Consulting (JMc) 5 January 2012

11 and nutsedge (Cyperus eragrostis). The understory of the redwoods features small patches of native plants characteristic of the coast redwood forest in the region, including hairy honeysuckle (Lonicera hispidula var. vacillans), Hooker s fairy bells (Disporum hookeri), wood strawberry (Fragaria vesca), and a unidentified violet, which may be the non-native Viola odorata but could be a native species. The invasive English ivy (Hedera helix) occurs in the understory and climbs the redwood trees. As part of the initial study for the campus development project, the site was examined for occurrences of 47 special status plant species that occur within the region (DDA 2011). Forty-five species were determined to not be present, while surveys were recommended for two species with low potential to occur on the site: deceiving sedge (Carex saliniformis) and swamp harebell (Campanula californica) Animal Species Habitat conditions within the site are highly degraded due to the dense infestations of non-native plants (Section ). Despite this, the drainage and surrounding vegetation may provide habitat for birds and small mammals, which can utilize the dense thicket of Himalayan berry for cover and food. ). These and other species may also obtain water from the drainage, which could also provide breeding habitat for amphibians such as Pacific chorus frog (Pseudacris regilla). As part of the initial study, the site was evaluated for the presence of suitable habitat for 29 special status animal species that occur in the region (DDA 2011). Habitat was determined not to be present for 20 species; notably, the drainage was deemed to provide suitable breeding habitat for California redlegged frog (Rana draytonii; DDA 2011). The site was found to have a low potential to be utilized by Cooper s hawks (Accipiter cooperii) and American peregrine falcon (Falco peregrinus anatum), though habitat on site is unsuitable for nesting by these species. Other species including Townsend s big-eared bat (Corynorhinus townsendii), hoary bat (Lasiurus cinereus), and San Francisco dusky-footed woodrat (Neotoma fuscipes annectans) were determined to have low potential to utilize the site. 2 Restoration 2.1 Restoration Site Restoration will take place within an approximately 0.15-acre area within 15 feet of the drainage ditch to the west, and five feet to the east (Figure 1). This area represents a contiguous area influenced by the hydrology of the drainage ditch, which can support native riparian plant species and be managed to attain the restoration goal and objectives away from the impacts of adjacent development. The 0.17-acre area west of the restoration site and east of the developed portions of the campus will be planted with native plant species adapted to moist conditions including riparian shrubs, as well as native grasses, as identified in the planting plan for the project (Lewis 2011b; Appendix B). This area will create a buffer between the campus and the riparian restoration site. Much of the restoration area is located outside of the San Lorenzo Valley Water District s parcels, and within the County right of way (Figure 1). County Environmental Coordinator Matt Johnston has indicated that this area is not going to be converted for use as a road and thus should be included in the riparian restoration for the site (M. Johnston, pers. comm. 2011). A portion of the right of way is Jodi McGraw Consulting (JMc) 6 January 2012

12 currently used by residents of the adjacent private parcels. Specifically, the southern portion is used for parking, while the northern portion is fenced within the yard of the adjoining landowner. As a result, successful restoration within the site will require coordination with the County Department of Public Works, which is responsible for the right of way, and the neighboring land owners. 2.2 Restoration Goal and Objectives The goal of the restoration is to enhance the native plant cover, species richness, and natural functions, including soil stabilization and provision of animal habitat, of the vegetation growing along and within a 0.15-acre area surrounding the drainage ditch east of the property. This goal will be attained through work toward four primary objectives, which represent four main phases of the restoration: 1. Protect native plants and the hydrologic function on site during development and exotic plant control, so that native plants established within the site can promote restoration; 2. Control or eradicate, where feasible, invasive plants that outcompete native plants and degraded habitat by native animals (Section ); 3. Establish native plant species to create the natural community structure and species composition of a creekside community, using plants salvaged from the site and other local sources; and 4. Maintain and promote growth and regeneration of an assemblage of native plants typical of a seasonal drainage within the coast redwood forest, to provide habitat, stabilize soil, and promote hydrologic functions. 2.3 Restoration Tasks The restoration objectives will be attained through tasks completed during four main phases, which correspond to the specific objectives. Table 2 summarizes the tasks associated with each phase, which are described in greater detail in this section Phase 1: Project Construction During the project construction phase, when contractors will prepare for and implement the development project (Section 1.1), the main objective of the restoration will be to prevent unnecessary damage to native plant species on site and avoid undesirable alterations to the hydrology of the drainage ditch. This objective will be attained through implementation of three tasks, which will also help promote restoration during invasive plant removal (Phase 2) Mark Plants for In Situ Protection Restoration of the site can be advanced by protecting native plants from unnecessary impacts associated with construction. Impacts to native plants will be avoided through the following: Installing construction fencing (e.g. 3-4 tall orange plastic fencing ) to delimit the limits of grading; and, Installing construction fencing or other protective barriers around trees and other native plants that are near construction areas and could be inadvertently impacted. Jodi McGraw Consulting (JMc) 7 January 2012

13 Table 2: Restoration objectives and tasks for each of four phases of the project. Phase Objective Tasks Description 1: Project Construction Protect native plants and the hydrologic functions on site during development and exotic plant control, so that native plants established within the site can promote restoration. Mark native plants for protection Salvage native plants Fence the drainage Install construction fencing to delimit the limits of grading and work. Mark individual plants within invasive plant management area to be protected in situ. Extract from the site native plants within or near the construction area for replanting (Phase 3) Fence the drainage ditch, particularly near areas of grading. 2: Invasive Plant Eradication Control and eradicate, where feasible, invasive plants that outcompete native plants and degraded habitat by native animals. Remove Himalayan blackberry Remove English ivy Remove invasive shrubs and trees including silver wattle and French broom Mow aboveground material and excavate main rootballs and rhizomes (lateral roots). Cut and remove vines; dig out roots. Invasive woody species adjacent to the restoration site can impact its success, and should be removed through cutting and controlled through follow up treatments, as needed. 3: Native Plant Revegetation Establish native plant species to create the natural community structure and species composition of a creekside community, using plants salvaged from the site and other local sources.. Develop Revegetation Plan Establish native shrubs along the restoration site Establish native herbs and vines Following invasive plant eradication, a revegetation plan will be developed based on the site conditions including retained species, soil conditions, and microrelief. Install creek dogwood (Cornus sericea ssp. sericea), wax myrtle (Morella californica), and hazelnut (Corylus cornuta ssp. californica) in areas outside of the drip line of the existing coast redwood. Re-plant native herbs salvaged from the site, including bog rush (Juncus effusus), and sedges (Carex sp.). Install chainfern (Woodwardia fimbriata), giant horsetail (Equisetum telmateia ssp. braunii), and thimbleberry (Rubus parviflorus) away from the canopy of shrubs and trees. 4: Restoration Maintenance Maintain and promote growth and regeneration of an assemblage of native plants typical of a seasonal drainage within the coast redwood forest, to provide habitat, stabilize soil, and promote hydrologic functions. Control exotic plants Re-establish native plants Address factors that will impede native plant establishment, growth, and survival Control invasive plants by re-treating those species that re-establish and detecting and eradicating new species. Where survival of initial plantings and natural recruitment insufficient, establish native plants through revegetation. Where native plant establishment is insufficient, identity and address potential causes. Jodi McGraw Consulting (JMc) 8 January 2012

14 Salvage Native Plants The southeastern portion of the restoration site features a relatively high density of herbaceous plants that will likely be impacted by construction of the off-site drainage facility to contain stormwater flows, and/or the invasive plant control work (Phase 2). These native plants, which cannot be retained in situ but can promote the ultimate restoration goal for the site, will be salvaged and propagated to increase their abundance for replanting, as feasible (Phase 3). Prior to construction, sedges (Carex spp.), rushes (Juncus spp.) and other perennial native herbs that will be impacted by the construction and/or the invasive plant control work, will be extracted using a shovel, placed in 1-5 gallon nursery cans, and stored in a suitable off-site location where they will be protected from herbivory and provided supplemental water as needed. Plants that reproduce and spread vegetatively will be divided before planting into pots, in order to increase their numbers Fence the Drainage To prevent grading or other activities that would impact the topography or hydrology of the drainage, the western area portion of the drainage adjacent to the project site will be fenced using orange construction fencing Phase 2: Invasive Plant Eradication A key objective of the restoration will be controlling and, where feasible, eradicating invasive plant species, which outcompete native plants and degrade habitat for native animals. This objective will be attained through three main tasks, which are summarized in Table 2 and described below Remove Himalayan Blackberry Himalayan blackberry currently covers much of the restoration site away from the immediate canopy of redwood trees (Section ). This invasive vine/shrub precludes growth of most native species and creates a dense impenetrable thicket that prevents native animals from accessing the drainage for water. Control of this species will be achieved through the following treatments (CalIPC 2004): 1. Remove existing aboveground biomass through mowing or other mechanical means, while avoiding impacts to native plants to be retained on site, which will be fenced or otherwise demarcated (Section ). If possible, this treatment should be conducted in spring when the plants are growing rather than dormant. 2. Remove root balls and rhizomes (lateral roots), to prevent resprouting, using tilling in dense monocultures, or shovels in areas around native plants. 3. Cut and remove new growth that emerges from vegetative biomass or seed. Several years of retreatment may be required, as the species has a long-lived seed bank. Foliar herbicides should be avoided, as this species produces edible berries that could be eaten by people in the area (CalIPC 2004). Jodi McGraw Consulting (JMc) 9 January 2012

15 Remove English Ivy English ivy is an invasive vine that occurs within the redwood trees and in the understory of the restoration area away from Himalayan berry. This vine can form a dense cover that can outcompete native herbs and can kill some trees, and produces toxic leaves and berries. Control of this species will be achieved through the following treatments (CalIPC 2004): 1. Cut and remove all aboveground biomass, including vines and all leaves in trees, which can be pulled down, and all vines and leaves on the ground. 2. Excavate and dispose of roots in order to prevent resprouting. 3. Remove any resprouts or seedlings that establish, by checking the site 3-4 times per year Remove Invasive Shrubs and Trees The northeastern portion of the project site currently supports French broom and silver wattle: invasive woody plant species that outcompete native plants and degrade habitat for animals (Section ). Control of these species will be achieved through the following treatments (CalIPC 2004): 1. Cut or otherwise remove all aboveground biomass. Initial removal of the established individuals may be achieved through grading of the site, to prepare it for development which will occur within a portion of the area currently infested. 2. Remove all resprouts or seedlings. This may require several years as both species resprout vigorously and have long-lived seed banks Phase 3: Native Plant Revegetation Restoration of the site will require establishment of native plant species to create the native community structure and species richness of a creekside community. The specific objectives of the revegetation are to: Establish native plants that would naturally occur along a small, ephemeral drainage within the coast redwood forests in inland portions of the San Lorenzo Valley. Install native plants that, when combined with those retained on site following construction and invasive plant removal, will create the layered structure of a natural community (i.e. trees, shrubs, and herbs). As the site features mature coast redwood and California bay laurel trees, the plantings will include shrubs and herbs. Use local stock, including plants salvaged form on-site (Section ) and those available from other local sources, to maximize success of the plantings by incorporating locally-adapted genetic complexes, and avoid genetic erosion or contamination associated with introducing nonlocal materials. Native revegetation will occur through the following specific tasks. Jodi McGraw Consulting (JMc) 10 January 2012

16 Develop Revegetation Plan Following removal of the invasive plant species (Phase 2), a revegetation plan will be developed based upon conditions of the site that cannot be currently observed due to the invasive plant species, or that might be altered during the course of their eradication. The revegetation plan will specify the following: A planting design, which will identify the species that will be planted and their spatial configuration, based upon the microhabitat conditions including soils, microrelief, and hydrology. Plant protection mechanisms including cages and fences, that will be designed to promote plant establishment; Soil amendment or watering regimes, designed to promote plant growth and reproduction. The following revegetation tasks describe preliminary aspects of the revegetation plan Establish Native Shrubs Native shrubs can provide habitat and food for a diverse suite of native animals. Species that will be installed include: Creekside dogwood (Cornus sericea ssp. sericea): a deciduous shrub approximately 4-12 feet in height, that inhabits moist areas below 9,000 feet; Wax myrtle (Morella californica): an evergreen shrub or small tree (6-30 feet in height) that occurs in redwood forests, amongst other communities; and Hazelnut (Corylus cornuta ssp. californica): a deciduous shrub or small tree (4-15 feet) that produces nuts and occurs in shady, moist places. These plants will be interspersed in a natural configuration on both sides of the drainage, in open areas away from the canopy of the coast redwoods. They will be protected from herbivory by deer using cages that will afford protection for the first three years, during which they are most vulnerable to the impacts of herbivory Establish Native Herbs and Vines Native perennial plants can promote restoration of the site by covering the soil and preventing erosion, and providing food and habitat for native animals. The following species to be installed were chosen to complement native species that are likely to naturally recolonize, such as tall flatsedge (Cyperus eragrostis), and because they spread relatively readily (e.g. vegetatively) when installed in appropriate conditions. Sedges (Carex spp.) salvaged and propagated, as feasible, from the site (Section ). Due to the difficulty in identifying and obtaining appropriate species, only Carex obtained from the site will be planted. Rushes (Juncus patens and J. effusus) salvaged and propagated from the site (Section ); Chain fern (Woodwardia fimbriata) from local stock in 1-5 gallon containers Giant horsetail (Equisetum telmateia ssp. braunii) from local stock in 1-5 gallon containers. Thimbleberry (Rubus parviflorus) from local stock in 1-5 gallon containers. Jodi McGraw Consulting (JMc) 11 January 2012

17 Other native herbs that can be readily salvaged and re-installed from the site may include: Wood strawberry (Fragaria vesca) Hooker s fairy bells (Prosartes hookeri) Herbs and vines will be planted away from the anticipated canopy of the shrubs, which will likely preclude herbaceous plant growth. Giant horsetail and chain fern will be planted within the drainage channel or on its berms; other species will be planted outside of the berms. Native herbs and vines vulnerable to herbivory will be protected using cages to promote survivorship, growth, and reproduction Phase 4: Restoration Maintenance The objective of the final phase of restoration is to maintain and promote growth and regeneration of a diverse assemblage of native plants typical of a seasonal drainage within the coast redwood forest, to provide habitat, stabilize soil, and promote hydrologic functions. This objective will be achieved through three main tasks Control Exotic Plants Occurrences of exotic plants will be controlled using methods appropriate for the site conditions and species. Controlling invasive species including those that are already on site such as Himalayan berry, English ivy, French broom, and silver wattle, will be important, as these species can recolonize the restoration area and outcompete native plants and degrade habitat for animals. It will similarly be important to detect and remove occurrences of new exotic plant species, such as panic veldt grass (Ehrharta erecta) and velvet grass (Holcus lanatus), which occur in the region and could colonize the area following initial clearing and planting. Occurrences of exotic species will be detected through quarterly monitoring of the site (Section 3.2.1) Re-establish Native Plants If mortality of the native plants installed in Phase 3 is high, and natural recolonization by native species is not sufficient, additional native plantings may be needed to attain the success criteria. The specifics of the additional plantings would be determined based on the conditions of the site Address Other Factors Impeding Native Plant Success As the intent of the restoration is to create a self-sustaining community, this phase will also include addressing any additional factors such as erosion, extensive herbivory, trampling, or other unforeseen factors that can limit plant growth, survivorship, reproduction, and establishment. 3 Adaptive Management and Monitoring Plan This restoration plan will be implemented through an adaptive management framework, which includes the following elements: Jodi McGraw Consulting (JMc) 12 January 2012

18 1. Success Criteria: specific aspects of the site that can be measured to evaluate success of the restoration at achieving its goal, which reflects the desired future condition of the site; 2. Monitoring protocols: steps that will be taken to evaluate success of the restoration and inform the need for additional or remedial management; 3. Adaptive management elements: steps that will be taken to enhance the effectiveness of the restoration program during implementation to promote attainment of the success criteria and goal. 3.1 Success Criteria The success criteria are designed to allow objective evaluation of the extent to which the restoration has achieved its goal (inset box). They identify target conditions for what can be achieved and naturally sustained, based upon its current conditions and anticipated conditions following implementation of the development project. Success criteria were based on target conditions, rather than the following alternative approaches for the reasons that follow: Use of replacement ratios for plantings: Since the site is highly degraded and supports few native plants, it would not be meaningful to gauge success based on a number of native plants replaced. Use of reference site: Because the drainage area is anthropogenic and will occur adjacent to a facility, using a natural reference site was also deemed an undesirable way to gauge success of this restoration project. Criteria for individual restoration objectives: Since the specific objectives of the restoration are designed to collectively contribute to the restoration goal, which reflects the desired future conditions of the site, the success criteria relate to the site conditions, rather than the effectiveness of the tasks (e.g. success of individual plantings, etc.). Restoration Goal and Success Criteria Goal: to enhance the native plant cover, species richness, and natural functions, including soil stabilization and provision of animal habitat, of the vegetation in the restoration site. Success Criteria 1. Total absolute native plant cover averaging at least 70%. 2. Native plant species richness (number of species) of at least 4/m 2 (alpha richness) and 18 species total (gamma richness). 3. Total absolute cover of exotic plants averaging less than 10%. 4. No significant impairments to the hydrologic functions of the ditch (e.g. soil erosion, deterioration of the channel) that would affect water quality of the ability of the site to support native plant species. 3.2 Monitoring The purpose of monitoring is to evaluate success of the restoration and inform the need for additional or remedial treatments to enhance effectiveness. Specifically, in years 1-4, monitoring results will be used to evaluate effectiveness of exotic plant control, success of the native plantings, and natural recolonization of the site by native species. It will also be used to identify any other factors might limit Jodi McGraw Consulting (JMc) 13 January 2012

19 native plant establishment, growth, and survival. During the fifth and final year of plan implementation, monitoring will be used to evaluate whether restoration has attained the success criteria. Restoration monitoring will be conducted through two complementary approaches: 1. Qualitative Site Assessments: Quarterly assessments of overall site conditions to identify the need for management during the year; and 2. Quantitative Assessment of Success Criteria Status: Annual monitoring to inform the subsequent year s management and ultimately assess success of the restoration Qualitative Site Assessment Qualitative assessments of the restoration site will be conducted quarterly (e.g. spring, summer, winter, and fall), to assess the following: 1. Site status: current cover of native and exotic plants, erosion, drainage issues, or other factors that would affect the restoration; 2. Treatment effectiveness: exotic plant control effectiveness, condition of plantings (e.g. survivorship, herbivory, etc.); 3. Need for remedial efforts: re-treatment of exotic plants, watering, protection or other horticultural treatments for plantings; erosion control or other activities to address hydrology. The specific items evaluated will vary depending on the phase of the restoration project. Quarterly assessments will include photomonitoring to evaluate general changes in the site conditions over time. Permanent photopoints will be established prior to implementation of the plan, and will be designed to enable examination of the entire site. Approximately 5-10 photographs are anticipated to be needed. Their locations will be marked using a piece of metal conduit capped to prevent injury, and recorded using a global positioning system to facilitate precise re-occupation Quantitative Assessment of Success Criteria Status Quantitative monitoring will be conducted annually to track progress toward the success criteria for the restoration, which will ultimately be assessed in the fifth year of the restoration plan. Each spring, when herbaceous plant cover is at its peak (May-June), plant species cover will be estimated within 10 permanent 5 m 2 plots which will be randomly located in the restoration area. The plot corners will be monumented using metal conduit and their locations will be recorded using a global position system (GPS), so that they can be reexamined in subsequent years. Within each plot, absolute plant cover will be estimated visually by species, using the following cover classes: <1%, 1%, 3% 5%, 8%, and 10%, and in 5% increments between 10% and 100%. Canopy cover will be measured using a spherical densitometer. Individual plot data will be combined to calculate mean native plant cover and species richness, which will be used to evaluate status toward the success criteria (Section 3.1). Jodi McGraw Consulting (JMc) 14 January 2012

20 3.3 Adaptive Management This restoration plan will be implemented as part of an adaptive management process, in which management is adjusted, as needed, based on treatment effectiveness and changed conditions, in order to attain the plan goal and success criteria. The elements of this restoration plan were developed based on the initial site conditions, anticipated site conditions following construction of the proposed project, and known aspects of the ecology of the system. During the course of plan implementation, it may be necessary to make adjustments to various components of the plan, in order to meet the plan s overall goal: to enhance the native plant cover, species richness, and natural functions, including soil stabilization and provision of animal habitat, of the vegetation in the restoration site. Plan components that could merit adaptations include: 1. Success criteria: Should the success criteria, including quantitative cover and species richness targets, prove inappropriate, they may be adjusted to better reflect the desired future conditions of the restoration site. 2. Treatments: Existing restoration treatments can be adjusted to address changes in circumstances, including the invasion of new species, the success of revegetation, and to otherwise enhance effectiveness. In addition, the scope of the restoration treatments may need to be expanded to address other factors that might limit plant establishment and growth. 3. Monitoring: The monitoring protocol may need to be adjusted to enhance its ability to track the status of the restoration, including by adding plots (i.e. increasing the sample size) or changing their size to address the site variability and configuration. Such adjustments made as part of the annual adaptive management process are examples; other changes may be needed during the course of management to restore the site. Such changes would be identified in annual reports and work plans. 3.4 Reporting Annual reports of plan implementation will be prepared by the restoration personnel and provided to the County of Santa Cruz Planning Department by January 31 of the year following implementation. Each annual report will include the following: 1. A description of the restoration treatments implemented during the year and to date; 2. A qualitative assessment of the site conditions (Section 3.2.1); 3. The quantitative assessment of the site and status toward attaining the success criteria (Section 3.2.2); 4. Recommended changes to the plan based on the adaptive management process (Section 3.3); and 5. A description of the recommended tasks to be implemented in the following year. Jodi McGraw Consulting (JMc) 15 January 2012

21 4 Plan Implementation 4.1 Anticipated Project Schedule The project tasks are estimated to be completed over the course of a five-year period, which will begin just prior to construction of the campus (Table 3). The annual work plans will provide calendars for activities within a given year, and identify the timing of seasonally-dependent activities such as exotic plant control treatments and planting. Table 3: Anticipated schedule for phases of the restoration project Phase Year1 Year 2 Year 3 Year 4 Year 5 1: Project Construction 2: Invasive Plant Eradication 3: Native Plant Revegetation. 4: Restoration Maintenance 4.2 Annual Implementation Schedule The five-year plan will be implemented through an annual cycle that includes the following: 3. Develop an annual work plan (October-December): The work plan will identify the specific tasks that will be completed during the following year, based on the plan and the existing site conditions and prior year s monitoring report (if available), and provide a budget and timeline for their completion. 4. Conduct restoration and monitoring (January - December): The work plan tasks will be implemented, with adjustments made based on changed conditions and monitoring during the year. 5. Prepare annual report (October - December): Prepare the annual report for the current year, and a work plan for the following year. 4.3 Personnel This plan will be implemented by the District, which will contract with qualified personnel to conduct the various restoration tasks. Monitoring, reporting, and planning (e.g. work plan and revegetation plan) will be conducted by a biologist with experience in the ecology and restoration, who can identify plant species and conduct quantitative analysis of plant community composition (Section 3.2). The restoration treatments will be conducted by technicians with experience in exotic plant control and revegetation, with oversight provided by the biologist to prevent inadvertent negative impacts due to the treatments. Jodi McGraw Consulting (JMc) 16 January 2012

22 4.4 Funding The District will fund implementation of the restoration plan. As required by the County of Santa Cruz Planning Department, the District will submit a copy of the annual work plan along with a letter indicating the intention to fund its implementation. Jodi McGraw Consulting (JMc) 17 January 2012

23 References Baudry Engineering, Inc Geotechnical Feasibility Study for Proposed Water District Operations Facility, Highway 9 and Highway 9, Santa Cruz County, California. December Brabb, E.E., 1989, Geologic map of Santa Cruz County, California: U.S. Geological Survey Miscellaneous Investigations Series Map I Cahill, R Telephone conversation between Jodi McGraw and Rodney Cahill, Engineer, Mesiti- Miller Engineering, regarding the Drainage Plan for the San Lorenzo Valley Water District s Campus Development Project. December 15, California Invasive Plant Council (CalIPC) The Weed Workers Handbook. California Invasive Plant Council. Berkeley, CA. May Denise Duffy and Associates Final Initial Study and Mitigated Negative Declaration for the San Lorenzo Valley Water District s Campus Development Project. Prepared for the San Lorenzo Valley Water District. February Johnston, M Personal communications between Matt Johnston, County of Santa Cruz Environmental Coordinator, and Jim Mueller, San Lorenzo Valley Water District General Manager, regarding restoration project on December 6, Lewis, G. 2011a. Riparian Buffer Area within the San Lorenzo Valley Water District s Campus Development Project. Gregory Lewis Landscape Architect. December Lewis, G. 2011b. Planting Plan for the San Lorenzo Valley Water District s Campus Development Project. Gregory Lewis Landscape Architect. Revised December PRISM Climate Group Geographic information system climate data for the United States. Downloaded from December Silvernail, D Application for Exception to Riparian Corridor and Wetlands Protection Ordinance for the San Lorenzo Valley Water District s Campus Project (Application No ). Letter to Samantha Haschert, County of Santa Cruz Planning Department. May 17, Exception to Riparian Corridor and Wetlands Protection Ordinance U.S. Department of Agriculture (USDA) Soil Survey of Santa Cruz County. Soil Conservation Service, United States Department of Agriculture and University of California. Jodi McGraw Consulting (JMc) 18 January 2012