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CC SR 20251007 03 - Landslide General Plan Amendments CITY COUNCIL MEETING DATE: 10/07/2025 AGENDA REPORT AGENDA HEADING: Regular Business AGENDA TITLE: Consider initiating General Plan Amendment proceedings to update references to the new Chapter 15.20 of the Rancho Palos Verdes Municipal Code RECOMMENDED COUNCIL ACTION: (1) Initiate General Plan amendment proceedings thereby having the Planning Commission, in an advisory role, make recommendations to the City Council on proposed text amendments to the General Plan elements to update references associated with the adopted amendments to Rancho Palos Verdes Municipal Code Chapter 15.20, entitled “Greater Portuguese Bend Landslide Complex Regulations on Land Use Permits.” FISCAL IMPACT: There is no fiscal impact since these amendment proceedings, which involve staff time, are budgeted annually in the Community Development Department/Planning Division budget as personnel costs. Amount Budgeted: N/A Additional Appropriation: N/A Account Number(s): N/A ORIGINATED BY: Brandy Forbes, Director of Community Development REVIEWED BY: Catherine Jun, Deputy City Manager CJ APPROVED BY: Ara Mihranian, AICP, City Manager ATTACHED SUPPORTING DOCUMENTS: A. Draft General Plan Amendments (Page A-1) B. Ordinance No. 692 BACKGROUND: On August 19, 2025, the City Council adopted Ordinance No. 692 (Ordinance), which repealed Chapter 15.20 of the Rancho Palos Verdes Municipal Code (RPVMC) and replaced it with a new Chapter 15.20, permanently prohibiting new residential construction in the Greater Portuguese Bend Landslide Complex. The Ordinance, however, does also allow property owners to replace, restore, or repair development within its existing footprint. 1 01203.0023 2045586.1 In general, when code sections are amended, staff must review all City regulatory documents to identify and update cross-references to the original code to ensure they are aligned with the new provisions. For example, references to Chapter 15.20 of the RPVMC were also identified in Sections 15.04.040 and 16.40.030 of the RPVMC. Updates to those references were incorporated into Ordinance No. 692 and became effective concurrently. Chapter 15.20 is also referenced in the Zoning Code (Title 17). However, because amendments to the Zoning Code first require Planning Commission review, the City Council initiated the code amendment proceedings by referring the matter to the Planning Commission for consideration, in an advisory capacity, with their recommendation being forwarded to the City Council. As such, the Planning Commission later adopted Resolution No. 2025-06 recommending approval of amendments to Title 17 to ensure alignment with the new Chapter 15.20. DISCUSSION: In reviewing the proposed code amendments to Title 17 (Zoning) for consistency with the General Plan, the following cross-references to Chapter 15.20 were identified: 1. The General Plan still references the prior title of Chapter 15.20. 2. The land movement information in the General Plan is only as current as 2018. As a result, staff recommends that the City Council initiate a General Plan amendment to update references to the prior title of Chapter 15.20 and also to incorporate the most recent information on land movement within the Greater Portuguese Bend Landslide Complex. If initiated, the City Council would refer this proposed General Plan amendment to the Planning Commission next, which, in an advisory role, will make recommendations on proposed text amendments and submit them to the City Council at a later date. This discussion by the Planning Commission would be scheduled for October 28, 2025. It should be noted that a General Plan may only be amended four times a year , and that initiating amendments to the General Plan to address amendments to Chapter 15.20 of the RPVMC will not result in exceeding four amendments for this year. CONCLUSION: The City Council is being asked to initiate General Plan amendment proceedings to update references to the Portuguese Bend Landslide Complex as well as amendments to Chapter 15.20 of RPVMC on building regulations associated with the Portuguese Bend Landslide Complex. 2 01203.0023 2045586.1 ALTERNATIVES: In addition to Staff recommendation, the following alternative actions are available for the City Council’s consideration: 1. Identify specific code criteria within the RPVMC that should or should not be amended. 2. Direct Staff to take no action at this time. 3. Take other action, as deemed appropriate. 3 DRAFT GENERAL PLAN AMENDMENTS The following are proposed amendments to the General Plan to update references to the landslide and Chapter 15.20. The page is referenced, and the full paragraph(s) to be revised are included, with the additions presented as underline and the deletions presented as strikethrough. These are available for Planning Commission discussion on September 23, 2025 and will be considered for Planning Commission recommendation to City Council at a duly noticed public hearing. Click here to view the full General Plan document. Page AA-2 II Acronyms and Abbreviations: LMA Landslide Moratorium Area LME Landslide Moratorium Exception ME Moratorium Exclusion Permit Conservation and Open Space Element- Page C-13 Under “Future Conditions” Traffic growth will come from expansion of existing houses and businesses, buildout of the remaining 439 vacant developable parcels (436 of which are zoned single -family residential) in the City, as well as visitors from outside the City. The 439 vacant parcels include many vacant parcels in the Portuguese Bend area. Although the Portuguese Bend area is currently under a building moratorium within the Greater Portuguese Bend Landslide Complex and has specific landslide regulations resulting from the landslide situation, this area contains over half of the City’s identified vacant lots. As such, only for purposes of conservatively estimating the maximum potential traffic growth at full buildout of the City, the traffic growth analysis assumes that the Portuguese Bend area may be developed at some time in the future. Additionally, a list was compiled of all pending projects in the City of Rancho Palos Verdes, as well as in the City of Rolling Hills Estates and the City of Los Angeles. These pending projects were included in the traffic growth analysis in order to maximize the potential future conditions resulting from buildout. Under “Effects of Landslides” The Greater Portuguese Bend Landslide Complex impacts the City’s circulation system along a 1-mile segment of Palos Verdes Drive South. Constant earth movement has resulted in this segment of Palos Verdes Drive South becoming distorted, warped, and broken, which impacts the smooth flow of traffic through this area of the City. However, the City continuously repairs and maintains this segment to ensure a safe flow of traffic. Conservation and Open Space Element Page COS-1 A-1 Table of Contents Figure 2A: Slope Stability Figure 2B: Greater Portuguese Bend Landslide Complex Map Conservation and Open Space Element Page COS-10 The Greater Portuguese Bend Landslide landslide Complex complex is the most studied and publicized landslide in the area, identified as a large complex that extends from the top of the ridge of the City to the ocean. The recently active portion of the Greater Portuguese Bend Landslide landslide Complex began in 1956 as a result of grading operations. Stability of portions of the landslide area has been in debate for many years, and other landslides, such as the South Shores landslide system, have been at equilibrium for some time. However, starting in 2023, development activities, heavy rain, and erosion may change changed the existing conditions and lead led to renewed failure of certain landslides that appeared stable.” The following four categories of slope stability have been mapped, shown in Figure 2 A, Slope Stability: Active Landslide, Old Landslide, Possible Landslide, and Non -Landslide Areas. The four categories of slope stability were developed from the landslide mapping developed as a portion of the Geotechnical and Public Safety Report for Cities of Rancho Palos Verdes, Rolling Hills Estates, and Rolling Hills (Envicom Corporation 1975). Old Landslide Areas are presently in a metastable condition and could change to Active Landslide Areas with minor changes in the natural or human-caused environment, although some Older Landslide Areas are in a stable condition and could be suitable for residential development (subject to detailed geologic investigations) and human habitation. The significance of the slope stability categories in terms of land use planning are described below (interpretations by Kling Consulting Group 2015). • Active Landslide Areas. Areas now undergoing downslope movement; extremely unstable ground not suitable for residential development. Possible use as passive recreational area, parks, or area of geologic interest, but unsuitable for construction of any new permanent structures, unless the movement is stopped by some natural or human-induced force. • Old Landslide Areas. Areas determined by investigative techniques by a geologist to have had past movement and/or identified in the California Department of Conservation’s landslide inventory maps that portray the location of prior failure. Landslide inventory maps show existing landslides and reveal the extent of past movement. These landslides have experienced downslope movement in the past but are no longer moving. Most of these areas would not be suitable for residential development without conclusive demonstration, through detailed geologic studies, that they are stable enough to accommodate both the activities of site preparation and long-term human habitation. • Possible Landslide Areas. Areas suspected to be a landslide area on the basis of topographic evidence, indicating less confidence in the landslide’s existence. A-2 Some of these areas may prove to be stable areas that have not experienced sliding at all, or are very ancient slide areas that are now fairly stable. Some of these areas may be suitable for residential development, but they would require detailed engineering geologic studies to show that they are stable enough for development and human occupancy. • Non-Landslide Areas. Areas where no natural landslides have been identified. A wide range of existing and potential slope stability exists within this category, and new landslides could be triggered in some areas by human activities, such as excavation. Most of the areas, however, would not be subject to slope failure if development were carried out properly. Although there is less chance of slope instability in this area, geologic and soil engineering investigations will still be required for any proposed development. As a consequence of these geologic conditions, existing and potential slope stability must be recognized as a prime consideration in determining land use within the City. Although some types of limited development may be possible within certain landslide areas, detailed geologic investigations are necessary to demonstrate the required degree of stability. Appropriate geologic investigations often precede certain developments in Non - Landslide areas of the City, as new ground failure could well be triggered b y human activities. Due to changed circumstances following severe weather events and advanced land movement in 2023, the Greater Portuguese Bend Landslide Complex, as described in more detail in the Land Use Element and shown in Figure 2B, is considered an Active Landslide Area and Slope Stability as shown in Figure 2A s hould be considered accordingly.” Conservation and Open Space Element COS-11 Figure 2A: Slope Stability [image to remain the same] Conservation and Open Space Element Added COS Page Figure 2B: Greater Portuguese Bend Landslide Complex A-3 Conservation and Open Space Element Page COS-23 The last four sensitive fauna species listed in Table 3 are sensitive wildlife that have been found to thrive in the various vegetation communities within or near the City. Two populations of El Segundo blue butterfly (Euphilotes battoides allyni) were found during focused biological surveys conducted in 2006. One population was found just north of Point Vicente in a large patch of coast buckwheat (36 observed), and the other population was found southeast of Point Vicente at the Fisherman’s access area (13 observed). Historically, Palos Verdes blue butterfly has been observed near the “switchback” area of Palos Verdes Drive East, within the landslide moratorium area Greater Portuguese Bend Landslide Complex, and in Agua Amarga Canyon. Federally designated critical habitat for Palos Verdes blue butterfly includes Fred Hesse Park, Agua Amarga Canyon, and the “switchback” area of Palos Verdes Drive East. Coastal California gnatcatcher habitat is coastal sage scrub vegetation. This habitat is protected and managed throughout the NCCP/HCP area and by the Endangered Species Act. The coastal population of cactus wren (Campylorhynchus brunneicapillus) nests in southern cactus scrub habitat dominated by extensive stands of tall prickly pear or cholla cacti. Conservation and Open Space Element Page COS-29 Add at the bottom of the page, “Due to changed circumstances following severe weather events and advanced land movement in 2023, the Greater Portuguese Bend Landslide Complex, as described in more detail in the Land Use Element and shown in Figure 2B above, is considered an Active Landslide Area and Resource Management Districts (Public Health & Safety) as shown in Figure 6 below should be considered accordingly.” A-4 Conservation and Open Space Element Page COS-43 Filiorum Reserve. This 189.8-acre parcel was purchased by the City from a private developer with a combination of funds from the California Coastal Conservancy, State Wildlife Conservation Board, and private donations, and is mostly located within the City’s landslide moratorium area Greater Portuguese Bend Landslide Complex. The site contains outstanding habitat and is used by hikers and equestrians. Land Use Element Page L-3 Table of Contents 9 Landslide Moratorium Area Greater Portuguese Bend Landslide Complex Land Use Element Page L-10 3.1 Hazard The Hazard areas possess extreme physical constraints, such as active landslide, sea cliff erosion hazard, and extreme slope of 35 percent and greater. These areas will be maintained as open space at this time, with very light intensity uses permitted, such as agriculture and passive recreational activities, for the protection of public health, safety, and welfare. These relate directly back to the analysis and policies in the Conservation and Open Space Element and the Safety Element in consideration of pu blic health and safety. The Hazard area designation includes an area of existing properties that are part of the Portuguese Bend community, located within the active Greater Portuguese Bend Landslide Complex landslide. This Plan recognizes that these properties are in a density range of 1–2 dwelling units per acre (d.u./acre), overlaid with the Hazard designation. The criteria and policies to regulate this area have been codified in the City’s Landslide Moratorium Ordinance Greater Portuguese Bend Landslide Complex Regulations on Land Use Permits (Chapter 15.20 of the City’s Municipal Code), which was originally enacted in September 1978. The purpose of the Greater Portuguese Bend Landslide Complex regulations Landslide Moratorium Ordinance is discussed in more detail in this Element. The Hazard area designation also occurs on other properties throughout the City that are blufftop lots along the City’s coastline. In many cases, the Hazard designation along the coastline has been applied to portions of these properties. Land Use Element Page L-11 Table 1 under notes, “* Residential includes the combined land use designation of Residential 1–2 d.u./acre and Hazard that is found within the active Greater Portuguese Bend Landslide Complexlandslide area.” A-5 Land Use Element Page L-12 1 Dwelling Unit per Acre. Land designated in this density in the original General Plan was of two primary types. First, areas identified in Chapter 2, Conservation and Open Space Element, as having high slopes, wildlife habitats, natural vegetation, canyons within the general area, some ancient landslide, plus some immediately adjacent areas included for continuity, are designated at this density. This density would tend to promote development that would have low environmental stress and be so designed under the use of overlay control districts that the physical and social impacts could be minimized. Much of the land originally designated at this density in these environmentally sensitive areas has now been re-designated as Open Space Preserve, as discussed above. Exceptions include the undeveloped Point View and Plumtree properties within the City’s Landslide Moratorium Area Greater Portuguese Bend Landslide Area. Second, areas in or near the Coastal Specific Plan District that were not yet committed to urban use at the time of the City’s adoption of its first General Plan (which is further described in Section 3.6, Specific Plan Districts) was designated at this density. Since the adoption of the first General Plan, most of this land has been committed to urban use, including the Lunada Pointe and Oceanfront Estates neighborhoods and the Trump National Golf Club. There currently remain only a few vacant lots within the Coastal Specific Plan District that are designated for future development at this density, mostly within the Trump National Golf Club project. Land Use Element Page L-19 State Facilities While there are no state facilities or land in the City, the Abalone Cove contains a State Ecological Preserve with important natural marine resources at the bottom of the Greater Portuguese Bend Landslide Complex. landslide area. Land Use Element Page L-25 Table 3 under notes, “* This combined land use designation occurs within the active Greater Portuguese Bend Landslide Complex landslide area.” Land Use Element Page L-26 Table 6 under notes, “* This combined land use designation occurs within the active Greater Portuguese Bend Landslide Complex landslide area.” Land Use Element Page L-31 9 Landslide Moratorium Area Roughly contiguous with the former RDA project area is the City’s Greater Portuguese Bend Landslide ComplexLandslide Moratorium Area (LMA). The area was originally considered the Landslide Moratorium Area (LMA) was originally established in 1978 in response to potentially unstable soil conditions and active landslide movement. Since A-6 1978, development activity has been strictly limited within the LMA. In 1993, a former City Geologist (Dr. Perry Ehlig) investigated the possibility of allowing development of certain areas within the boundaries of the LMA by establishing overlay zones. Dr. Ehlig divided the LMA into 8 separate zones and provided suggested guidelines for permitting development in each area based on geologic characteristics. The City considered Dr. Ehlig’s findings, but decided not to proceed with establishing overlay zones. The specific restrictions imposed within the LMA are described in the City’s Landslide Moratorium Ordinance (Chapter 15.20 of the City’s Municipal Code). In general, properties in the LMA that are currently developed with residential structures are permitted to make limited improvements if the City grants a Landslide Moratorium Exception (Exception). New construction is not permitted on properties in the LMA that are not currently developed with residential structures unless a Moratorium Exclusion (Exclusion) is granted, which would effectively remove the subject properties from the LMA. In 2002, a group of Portuguese Bend property owners filed an Exclusion application to exclude their undeveloped lots within the area known as “Zone 2” from the LMA. Zone 2 is a portion of the LMA that had been designated by the late Dr. Perry Ehlig in 1993 as being potentially suitable for development. Shortly after this Exclusion application was deemed incomplete for processing, the applicants filed suit against the City. Eventually, the case (Monks v. Rancho Palos Verdes (2008) 167 Cal.App.4th 263) was de cided in the applicants’/plaintiffs’ favor in December 2008, the City being found to have taken the plaintiffs’ property by virtue of preventing the development of their undeveloped lots. The City has been ordered to remove regulatory impediments in its Mu nicipal Code that prevent the development of the 16 Monks plaintiffs’ lots. The City began this process with the adoption of Ordinance 498 in 2009 to allow the Monks plaintiffs to apply for Exceptions for their lots. The City began issuing Exception permits for these properties in 2010. At the same time, the City was considering broader revisions to the Landslide Moratorium Ordinance that could also permit the owners of the other undeveloped lots in Zone 2 to be developed with new residences. Although this discussion has had been tabled at this the time, if enacted, this it would have resulted in the possible future development of new residences on existing legal lots in Zone 2 within the Portuguese Bend community. Additionally, in early 2016, a code amendment was adopted, revising the Landslide Moratorium Ordinance that alloweds the property owners of the 94-acre Point View property and the 28-acre Plumtree property to be developed with one dwelling unit on each lot plus ancillary structures. The City experienced an unprecedented and unanticipated acceleration in land movement in the Greater Portuguese Bend Landslide Complex following the historic winter rains of 2022-23 and 2023-24, which caused significant damage to local homes, roads, utilities, and other vital infrastructure. On October 3, 2023,the City Council adopted Interim Urgency Ordinance No. 674U, which put into immediate effect a moratorium on construction in the Greater Portuguese Landslide Complex, and subsequently extended the Interim Urgency Ordinance for the maximum allowed two-year timeframe. A-7 On August 19, 2025, City Council adopted amendments to Chapter 15.20 of the City’s Municipal Code, now titled Greater Portuguese Bend Landslide Complex Regulations on Land Use Permits. New construction is not permitted on properties in the Greater Portuguese Bend Landslide Complex that are not currently developed with residential structures. Properties within the Complex may be permitted to make limited improvements if the City grants a Landslide Exception Permit (Exception). A property may apply for a Landslide Exclusion (Exclusion), which would effectively remove the subject properties from the Greater Portuguese Bend Landslide Complex. In addition to the consideration of new development on existing vacant lots in the LMA, there have been inquiries through the years to consider excluding certain larger undeveloped properties from the LMA to allow for future development. The City has yet to act upon a request for an Exemption. Safety Element Page S-3 Table of Contents Figure 3A: Landslide Inventory Figure 3B: Greater Portuguese Bend Landslide Complex Map Safety Element Page S-23 Translational or Block Slides: These slides are the largest, most impressive type of landslide. They involve a single coherent mass that translationally moves down-slope with little rotation or backward tilting. The basal failure plane (rupture surface) is controlled by planar zones of weakness, such as bedding, foliation, jointing or a formation contact, or fault. These failures typically occur in layered rocks of sedimentary or metamorphic origin where lateral support is removed by erosion or grading. The Portuguese Bend Landslide is a complex version of a translational landslide. The Portuguese Bend Landslide has been conductive to ground failure for approximately 250,000 years and has been officially mapped as a landslide complex before the 1950s. While the history of landslides dates back, the current slippage began in 1956, coincident with the construction of the Crenshaw Boulevard extension, south of Crest Road, along the top of the ancient landslide complex. Another possible contributing cause of the sliding was the construction of hundreds of homes on and above the unstable rock and soil in the early 1950s prior to the slide. Due to changed circumstances following severe weather events and advanced land movement in 2023, the Greater Portuguese Bend Landslide Complex Map was expanded to include active areas that were triggered by atmospheric rivers and extreme high winter rainfall accumulations in the winter of 2022 -2023 and again in the winter of 2023-2024. The newly-mapped area is shown in Figure 3B. Safety Element Page S-24 A-8 Landslides in the City can be grouped into two major landslide systems that represent complex groups of smaller coalescing landslides: the Greater Portuguese Bend Landslide Complex and the South Shores. Smaller, isolated landslides are scattered throughout the City, outside the two major systems (Figure 3A, Landslide Inventory Map). The Greater Portuguese Bend Landslide Complex is the most studied and publicized landslide in the area, and perhaps in the Los Angeles Basin. The Portuguese landslide Greater Portuguese Bend Landslide Complex has been mapped as a large ancient complex that extends from close to the top of the ridge of the city to the ocean. The most recent Early recorded movement began in 1956, apparently as the result of grading operations, and involved movement in about one -third of the system. The recently active portion is shown on Figure 3B below 19. This area includes the Abalone Cove, Klondike Canyon, and the Portuguese Bend Landslides. The upper limit of the landslide has been under debate for many years. The Landslide Inventory Map (Figure 3A) places the ancient landslide scarp at the Valley View Graben adjacent to Crest Road. The Valley View Graben is a narrow valley interpreted as the remnant of the original pull-away at the top of the slide mass. Previous maps by Dibblee (1999) and others place the top of the landslide much further down slope from the Valley View Graben. The more recently adopted Greater Portuguese Bend Landslide Comp lex Map is shown on Figure 3B. Safety Element Page S-25 Figure 3A: Landslide Inventory [image to remain the same] Safety Element Added S Page Figure 3B: Greater Portuguese Bend Landslide Complex A-9 Safety Element Page S-26 In the lower portion of the landslide, Palos Verdes Drive South transverses the landslide along with water and sewer lines. The roadway and pipelines are under constant scrutiny to determine areas in need of repair. The roadway is modified as necessary, more recently due to accelerated land movement that began in 2023 this has required major and ongoing by minor grading and pavement repair. The pipelines have all been placed aboveground so that easy observation and maintenance can be performed. The risk to the roadway and pipelines is significant should portions of the as the Greater Portuguese Bend Landslide Complex haslandslide accelerate. Due to changed circumstances following severe weather events and advanced land movement in 2023, the Greater Portuguese Bend Landslide Complex Map was expanded to include active areas that were triggered by atmospheric rivers and extreme high winter rainfall accumulations in the winter of 2022 -2023 and again in the winter of 2023-2024. The newly-mapped area is shown in Figure 3B and is considered an Active Landslide Area and the Landslide Inventory in Figure 3A and the Landslides & Liquefaction in Figure 4 should be considered accordingly” Safety Element Page S-29 5.9 Coastal Cliff Retreat A-10 The Palos Verdes Peninsula coastal cliffs are exposed to wave energy and subject to erosion and cliff retreat. Cliff retreat is the landward migration of the cliff face as a result of erosion processes, including ocean, wind, and gravity. This chronic coastal evolution plagues the City’s infrastructure and threatens the communities that are situated above and adjacent to these cliffs. Cliff retreat rates from the Point Vicente area north are approximately 0 to 0.77 meters (2.5 feet) per year, and has locall y retreated more than 50 meters (180 feet) within a 65-year period (Hapke and Reid 2007). Cliff retreat rates in the Point Fermin area are estimated at between 0 to 0.95 meters (3 feet) per year, and has locally retreated more than 60 meters (197 feet) in 65 years (Hapke and Reid 2007). Along the Greater Portuguese Bend Landslide Complex, shoreline erosion removes stabilizing support. A-11