Ballona Creek Greenway Plan Greenway Plan
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BALLONA CREEK GREENWAY PLAN GREENWAY PLAN Introduction The Ballona Wetlands Mar Vista Culver City Mid-City Implementation Introduction The Ballona Creek Greenway Plan Greenway Plan. The Plan reflects Reach 4: Mid-City describes opportunities to reconnect stakeholder recommendations for The Ballona District residents with their creek, create a green access that would complement wetlands The under-utilized Mid-City reach of Ballona Creek corridor of trails and points of access, restoration. Ballona Creek can be redefined by Watershed enhance habitat, mitigate stormwater enhancing its creek-side character with Reach 2: Mar Vista runoff, redevelop land to improve distinctive native plants, landscape I-10 Adams Channel Reaching Out Ballona watershed functions, re-establish riparian treatments, and trails that connect and Creek Through Mar Vista, Ballona Creek’s Sepulveda areas, and increase the health and beautify neighboring residential and Channel presence can be enhanced by continuing SR-90 Centinela sustainability of the region. business districts. Creek the Greenway experience into the I-405 The Reach Plans summarize design neighborhoods opportunities in general terms, focusing bordering the on trail connections, gathering and entry creek. Urban points, stormwater mitigation, and street forestry, pedestrian Cochran design. enhancements, and Reach 4 Mid-City Gateway / Ballona Creek Park extensions of the The Ballona District Each Reach Plan features at least one Hauser Greenway landscape Community Crossings / Creek Crossings site-specific Early Action Plan, reflecting I-10 Fairfax are some of the Breaking Through / the ideas of stakeholders developed elements that can Ballona Regional Park during design charrettes. Following each reinforce connections. Adams Early Action Plan is a Vision Plan that I-405 Tributary Trails / Reach 3 Culver City Creative Confluences integrates a naturalized stream with the Reach 3: Culver City Creek Connections surrounding community. These plans can Creek Connections serve as advance planning for the U.S. Improving connections Sepulveda Channel Army Corps’ Lower Ballona Ecosystem to local parks C r e e k Restoration Feasibility Study. integrates Ballona a Creek with the Culver Reach 2 Mar Vista Reach 1: Ballona Wetlands City neighborhoods. l o n Reaching Out l The Coastal Centerpiece a The Greenway Plan Milton B While the Ballona Wetlands are a balances access with Reclaimed Open Space / Creekside Park defining feature of the Los Angeles Centinela privacy for residents Centinela coast, the interdependent features that Creek Permeable Parking / bordering the creek. Reach 1 Ballona Wetlands Creekside Cafe comprise the wetlands as a system are Coastal Centerpiece disconnected from each other and highly disturbed. Planning for the restoration of this wetland system is a larger effort outside the scope of the Ballona Creek I-405 28 BALLONA CREEK GREENWAY PLAN Cochran Gateway / Fairfax Ave BALLONA Ballona Creek Park CREEK La Cienega Blvd MID-CITY Cochran Ave Washington Hauser Blvd I-10 Freeway I-10 Freeway Community Crossings Adams Blvd / Creek Crossings ADAMS Venice Blvd Fairfax National Blvd CHANNEL Breaking Through / Ballona Regional I-405 CULVER Park Freeway CITY Duquesne Ave Mar Vista Adams La Cienega Blvd Palms Blvd Park Tributary Trails / Creative Culver Blvd Overland Ave Confluences SEPULVEDA BALDWIN CHANNEL Venice Blvd HILLS STATE PARK Washington Pl Sepulveda Blvd Ballona Creek Greenway Plan Legend MAR VISTA Washington Blvd Inglewood Ave Sepulveda Channel Jefferson Blvd Site Design Location Centinela Ave Trails LADERA Gateway Parks HEIGHTS SR-90 VENICE Culver Blvd Open Space Milton CENTINELA Centinela Permeable Parking / Reclaimed Open Space / CREEK Centinela Ave Urban Forestry SR-90 Creekside Park Creekside Cafe Jefferson Blvd Permeable Paving/ MARINA Smart Parking DEL REY I-405 Freeway Stream Naturalization Lincoln Blvd Playa Vista LOYOLA Biotreatment SANTA Ballona Creek MARYMONT BALLONA CREEK MONICA Wetlands UNIVERSITY Complete Streets BAY Culver Blvd Falmouth Ave Green Building Conversions Vista del PLAYA Mar DEL REY BALLONA CREEK GREENWAY PLAN 29 Core Approaches Greenway Plan provides a preliminary Green Building Conversions impacts flooding are constrictions such as Pervious Paving hydraulic modeling evaluation of a Existing structures can be retrofitted bridges. Widening the channel typically Pervious Paving replaces impervious naturalized channel. to capture and use rainwater, increase requires bridge replacement to eliminate surfaces throughout a range of land uses permeability, and connect to the the constriction. Combined Approaches to increase stormwater infiltration and surrounding landscape. Redevelopment Complete Streets The Los Angeles Regional Curve reduce flooding. zones can factor these improvements into Complete Streets provide multiple (2006) developed by Natural Channel new construction. Biotreatment benefits for pedestrians, cyclists, Design, Inc. was used for initial channel Biotreatment relies on the action of soil automotive traffic, stormwater Restoration Planning naturalization planning. The regional and plant microorganisms to break down management and habitat enhancement. Channel Design curve plots the relationship between pollutants. Biotreatment works well in Features in a typical Complete Street Naturalization of Ballona Creek has watershed size and channel width, depth, bioswales, detention or retention basins, may include conversion of some parking long been considered an impossibility. and area for waterways at bankfull flows subsurface trenches, and treatment spaces to traffic-calming “bulb-outs” and/ Extensive development to the edges within the same climatic and geographic wetlands. or bioswales or rain gardens; consistent of the channel’s right-of-way limits area as Ballona Creek. The regional tree canopy; permeable paving in parking restoration of the historical floodplain. curve was used to determine the width of Urban Forestry and Greenway zones; and bicycle “sharrows” indicating Observations of partially channelized the channel bottom in the development Landscape the appropriate path of travel for bicycles streams and examples of partial of the Greenway Plan and site designs Tree canopies reduce the urban heat in the traffic lane. naturalization of urban waterways offer presented herein. island effect, increase infiltration of clues to returning some stream functions stormwater, beautify communities, and Street Narrowing to Ballona Creek. enhance habitat. Native landscaping Street Narrowing can create space for (Top) Channel naturalization re- reduces dependence on irrigation and Complete Streets features or channel To maintain existing levels of flood establishes riparian habitat while trail and provides habitat for birds and small greenway improvements. Complete or protection while converting from a right-of-way landscape provide upland animals. partial street closures are another tool to concrete channel to one with a natural habitat and recreational access. improve open space and connections. bottom with some riparian/wetland Channel Naturalization vegetation requires increasing the overall (Left) A typical Complete or Green Channel naturalization removes concrete Smart Parking cross-sectional area of the creek and Smart Parking concepts reduce the Street enhances safe pedestrian and from the channel bottom, accommodating channel. Increasing the cross-section negative visual and watershed impacts of bicycle access through the traffic calming restoration of some stream function. The is achieved by widening the channel parking areas by increasing permeability effects of a continuous tree canopy, Lower Ballona Ecosystem Restoration within the right-of-way, adding low and biotreatment and/or reducing the curb extensions and marked shared Feasibility Study will explore channel floodwalls, and/or increasing the width footprint of parking area square footage. lane markings. Curb extensions double naturalization potential in detail. The of the right-of-way. Another factor that as rain gardens for the treatment of stormwater runoff. The Ballona Creek Greenway Plan uses these common BMPs to achieve water quality, (Right) Urban Forestry and native plants habitat, livability and sustainability goals. They can be combined and applied to specific land improve habitat connectivity for birds uses that affect watershed function. while creating pocket parks for residents. Street Narrowing slows traffic, enhancing the pedestrian zone. 30 BALLONA CREEK GREENWAY PLAN BALLONA CREEK GREENWAY PLAN 31 Hydraulic Modeling 1968 County Capital Storm: While the The Vision Plans, which propose I-10 100’ 100’ In 2008, initial channel naturalization Capital Storm for Ballona Watershed naturalized channels for the Mid-City Adams LAC - 23,300 CFS (117.05’) cross-sections for four reaches were is in the process of being updated, the and Culver City reaches (pp.52-53, 58- Channel Ballona developed using Manning’s Equation as a calculations performed in 1968 remain 59, 62-63, and 66-67) incorporate the Creek reference for estimating channel capacity. the current standard. These standards modeled channel cross-sections into Sepulveda Cross-sections for the upper two miles were used during planning to evaluate their designs. The Vision Plans for Mar Channel As-Built - 11,011 CFS (101’) LAC - 23,300 CFS (99.3’) of the creek (National Boulevard, Culver the capacity of both the existing and Vista and Ballona Wetlands (pp. 38-39 SR-90 LBERF - 10,051 CFS (100.25’) As-Built - 11,011 CFS