CHAPTER 6 Safety and Noise
This chapter has two sections: Safety and • Calaveras Fault, northern segment: 11 Noise. percent SAFETY • Concord Fault: 4 percent • Mt. Diablo Thrust Fault: 3 percent Every general plan in California must have a • Greenville Fault: 3 percent “safety element” that addresses natural and manmade hazards and dangers. This section of General Plan 2025 examines and aims to reduce See Figure 1, Regional Faults and Probabilities, the potential risk of death, injuries, property page 6-2, and Figure 2, Area Faults, page 6-3. damage, and economic and social dislocation The City’s objectives are to prevent geologic resulting from fires, floods, earthquakes, land- hazards in new projects and reduce the risk of slides, and other hazards. these hazards in existing developed areas. This section is presented in seven parts: • Seismic and Other Geologic Hazards GOAL 1 • Flooding Protect life and property • Hazardous Materials from geologic hazards. • Fire Hazards
• Public Safety Policy 1.1. Reduce the potential effects of • Disaster Response seismic and other geologic hazards, including slope insta- • Water Supply bility.
SEISMIC AND OTHER Action 1.1.1. Identify areas prone to seismic and other geologic hazards, in- GEOLOGIC HAZARDS cluding slope instability. The United States Geological Survey (USGS) has established probability estimates for sig- Action 1.1.2. Establish minimum road widths nificant earthquakes (magnitude 6.7 or greater) and clearances around struc- between 2003 and 2032. The following prob- tures at risk from known geo- abilities are estimated for faults in and around logic hazards. Walnut Creek: Action 1.1.3. Review and update the existing • Hayward/Rodgers Creek Fault: 27 maps of geologic hazards. percent
April 4, 2006 Walnut Creek General Plan 2025 6-1 Chapter 6, Safety and Noise
CONCORD/ GREEN VALLEY FAULT RODGERS
Vacaville
Sonoma Napa CREEK Fairfield
FAULT
Vallejo 4% SAN 27%
Martinez Concord San Rafael Richmond Walnut Creek Planning Area
Berkeley Pacific THRUST MT.DIABL FAULT GREENVILLE Ocean ANDREAS
Oakland HAY O San Francisco WARD 3% 3% Hayward F San A FAULT Pleasanton SAN Francisco ULT Bay 11%
Fremont 21% CALA
VER GRE Redwood F City AULT AS GORIO Palo Milpitas Alto
San Jose
FAULT 10% Legend ProbabilityProbability of 6.7 Richter scale earthquake, 2003 to 2032
10% or more
FAULT E 5-9.9% in Lomx te n t o a 1-4.9% P f Rupture rieta
Source: USGS Working Group 2002 (2003) Quake
0 5 10 Miles
Figure 1. Regional Faults and Probabilities
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Concord Pleasant Hill
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Rudgear Rd
Tic e V alle y B lvd
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R o s s m o o r P k w y
Area Faults
Concord Highways
Lafayette Major Roads Las Trampas City Limit Mt. Diablo Thrust N. Calaveras Planning Area Boundary Alamo N. Calaveras (extension) South Hampton and Franklin Walker Canyon Alquist-Priolo Earthquake Fault Zone Miles 00.511.520.25
Base Map Data: January 16, 2004 Source: USGS, 1994 Figure 2. Area Faults
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Action 1.1.4. Require appropriate mitigations and property from earthquake- for new development or rede- induced hazards. velopment in areas prone to seismic and other geologic haz- Action 1.2.5. For development proposals ards. submitted in areas near high or very high liquefaction- Policy 1.2. “Limit development within susceptibility areas, require a high-risk geologic areas to a geotechnical evaluation to iden- maximum density of one tify hazard mitigation measures dwelling unit per 20 acres.”1 needed to reduce the risk to life and property from liquefaction- Action 1.2.1. “Identify high risk areas after induced hazards. taking into account soil stabil- ity, history of soil slippage, proximity to earthquake faults, FLOODING slope grade, accessibility, and Historically, several streams in the Planning drainage conditions, and con- Area have flooded, including Walnut Creek, tinue to assign low intensity Las Trampas Creek, Grayson-Murderers uses, not exceeding a density of Creeks (particularly in the Eccleston Avenue one dwelling unit per 20 acres, area), and San Ramon Creek (primarily at the to such areas. Responsibility: confluence of the waterways downtown). City Council.” See Figure 3, Smaller streams subject to flooding include Liquefaction Susceptibility, Tice Creek (particularly in the Castle Hill page 6-5, and Figure 4, Mapped area)—and the Walnut Boulevard channel Landslides and Slopes Greater (also known as Homestead Creek) between than 15 Percent, page 6-6. Homestead Boulevard and Sierra Drive. (See Figure 5, Flood Zones, page 6-8.) Action 1.2.2. As updated seismic-hazard zone maps become available, incorporate them in the general plan. GOAL 2 Action 1.2.3. Identify areas where surface Reduce the potential for ruptures are most likely to oc- flooding in flood-prone cur and cause damage to hu- areas. man-made structures, such as dams. Policy 2.1. Reduce the risk of property Action 1.2.4. For development proposals damage and personal injury submitted in areas near earth- due to flooding. quake fault zones listed under the Alquist-Priolo Act, require a Action 2.1.1. Limit the amount of impervious geotechnical evaluation to iden- surface in flood-prone areas. tify hazard mitigation measures needed to reduce the risk to life Action 2.1.2. Limit runoff in flood-prone ar- eas.
1 Policy 1.2 and Action 1.2.1 address the requirements of Measure P, Ord. 1781, 11/5/91, Sections 3g and 3h. See Appendix B for the complete “Walnut Creek Hill- side/Open Space Protection Ordinance,” Measure P.
6-4 Walnut Creek General Plan 2025 April 4, 2006 Chapter 6, Safety and Noise
Concord Pleasant Hill
d lv T t B AR ea B Tr
O a k G r o v e R B d a Lime Ridge n c Geary Road r Open Space o f t R t d d Boundary B R S y e u ll Oak n a e i o V n a i ac a M n g Y
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C a s t le R Hwy 24 o c k R BART d
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Rudgear Rd
Tic e V alle y B lvd
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Liquefaction Susceptibility Water bodies
Low Highways Medium Alamo Major Roads High City Limit Very High Planning Area Boundary Miles 00.511.520.25 Note: Areas with no color are classified as having "Very Low" liquefaction susceptibility. Base Map Data: January 16, 2004 See text for further explanation of categories. Source: USGS Open File 00-444, 2000 Figure 3. Liquefaction Susceptibility
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Pleasant Hill Concord
d lv T t B AR ea B Tr
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Rudgear Rd
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Percent Slope Landslides 0 - 15% Alamo Highways 15 - 30% Major Roads 30 - 49% City Limit Miles 00.511.520.25 > 49% Planning Area Boundary Base Map Data: January 16, 2004 Source; USGS 1979 Regional Slope Stability Map, 1979; California Division of Mines and Geology, 1995, 1996. Figure 4. Mapped Landslides and Slopes Greater than 15 Percent
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Action 2.1.3. Work with the County to adopt similar standards for unincor- porated parts of the Planning Area.
Action 2.1.4. Collect drainage fees for pro- jects in designated drainage- improvement areas.
Action 2.1.5. Work with creekside property owners to reduce and mitigate flood hazards.
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P in e
C r Concord e e Pleasant Hill k
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Rudgear Rd
Tic e V alle y B lvd
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100-Year Flood Zones Natural creek Channel Highways Major Roads City Limit Planning Area Boundary Alamo
Miles 00.25 0.5 1 1.5 2
Base Map Data: January 16, 2004 Source: FEMA Flood Insurance Rate Maps,, 1996, 2002 Figure 5. Flood Zones
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HAZARDOUS MATERIALS Action 3.1.1. Work with Central Contra Costa Solid Waste Authority Federal, State, and local laws regulate the pro- (CCCSWA) to ensure that op- duction, storage, handling, and disposal of tions are available for: hazardous materials and waste. Hazardous materials are those that, because of quantity, • Full-service hazardous-material dis- concentration, or physical or chemical charac- posal teristics, pose a significant present or potential hazard to human health and safety or to the • Household and small business hazard- environment. They include industrial wastes, ous-waste disposal pesticides, radioactive wastes, asbestos, and • Convenient, economical drop-off combustible fuels. Household hazardous and/or pickup of used motor oil and wastes include pesticides, waste oil, paint antifreeze supplies, car batteries, and pool chemicals. • Convenient, economical drop-off Hazardous materials are transported through and/or pickup of universal waste (e.g., Walnut Creek on the area’s primary transpor- computer monitors, televisions, con- tation routes—Interstate 680, Highway 24, and sumer electronic devices, batteries) Ygnacio Valley Road – and via underground pipelines. Policy 3.2. Prioritize safety needs of non- industrial land uses. Both the State and the federal government re- quire businesses that store or handle hazard- Action 3.2.1. Carefully examine proposed ous materials to have inventory and reporting mixed-use areas and plans with programs. Businesses that store more than 55 respect to the presence or pro- gallons of liquid hazardous materials or 500 spective presence of hazardous pounds of solid or 200 cubic feet of com- materials. pressed gases must also file an annual busi- ness plan. The plans must establish incident Policy 3.3. Incorporate hazardous- prevention measures, hazardous-materials- material-abatement provisions handling protocols, and emergency-response- in zoning and subdivision de- and-evacuation procedures. The Contra Costa cisions and entitlement per- County Fire Protection District enforces the mits. business plans. Policy 3.4. Work with federal and state Walnut Creek households may dispose of haz- authorities to ensure that any ardous waste at three County-provided collec- transport of hazardous materi- tion centers. None are within the Planning als through Walnut Creek is at Area. the highest standard of safety.
Action 3.4.1. Designate hazardous-material carrier routes that direct haz- GOAL 3 ardous materials away from populated and other sensitive Reduce dangers from areas. hazardous materials. Action 3.4.2. Prohibit hazardous-materials transport vehicles from parking Policy 3.1. Facilitate the proper disposal on city streets. of hazardous materials.
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Action 3.4.3. Require, as much as possible, adjacent to the city limits on Geary Road. (See that new pipelines and other Figure 6, Fire Stations and Fire Service Areas channels carrying hazardous in Walnut Creek, page 6-12.) materials be placed to avoid residential areas and, in particu- lar, areas where the population Urban Fires is less mobile (e.g., convalescent The risk of structural fires within Walnut homes). Creek is minimal. Fire-fighting resources are adequate, development continues to comply Policy 3.5. Require that soils, groundwa- with applicable building codes, structures are ter, and buildings affected by relatively new and in good condition, and the hazardous-material releases CCCFPD implements a vigorous building- from prior land uses, and lead inspection program. Emergency access is good and asbestos potentially pre- in all areas. sent in building materials, will not have the potential to ad- versely affect the environment Wildland Fires or the health and safety of resi- Walnut Creek is surrounded by more than dents. 2,700 acres of undeveloped hillsides desig- nated as open space. These areas pose a poten- Action 3.5.1. Require an environmental in- tial fire hazard to adjacent development. vestigation for hazardous mate- rials when reviewing applica- The level of risk of wildland fire is determined tions for new development in by a number of factors, including the follow- former commercial or industrial ing: areas. • Frequency of critical fire weather Policy 3.6. Require that new development • Percentage of slope and redevelopment protect • Existing fuel (vegetation, ground cover, public health and safety from building materials) hazardous materials. • Adequacy of access to fire suppression Action 3.6.1. Require environmental investi- services gations stipulated by State and • Water supply and water pressure County regulations for potential hazardous material releases The California Department of Forestry and from prior uses, as well as for Fire Protection (CDF) has mapped the relative lead and asbestos present in wildfire risk to areas of significant population building materials. by intersecting residential housing density with proximate fire threat. (See Figure 7, Wild- land-Urban Interface Fire Threat, page 6-13.) FIRE HAZARDS The map shows four risk levels: Moderate, The Contra Costa County Fire Protection Dis- High, Very High, and Extreme. The CDF map trict (CCCFPD) provides fire-protection and shows that no part of the Planning Area faces first-responder emergency-medical services to an “extreme” threat. The map shows that CDF Walnut Creek and the Planning Area. The dis- gives much of the city a “very high” classifica- trict has 30 fire stations. Three of the stations tion, principally because CDF maps the wild- are located within Walnut Creek city limits; a land fire zones to include a 1.5 mile buffer. As fourth is located within the Walnut Creek a result, the higher fire-threat levels of the Planning Area and another station is located
6-10 Walnut Creek General Plan 2025 April 4, 2006 Chapter 6, Safety and Noise open space areas extend into much of the ur- building materials in develop- banized Walnut Creek on the map. ments in and on the edges of higher risk areas. (See Figure 7, Shell, Lime, and Las Trampas Ridges all have page 6-13.) high fire-hazard potential, and all lie above the 450-foot water service level of the East Bay Action 4.2.3. Establish minimum road widths Municipal Utility District (EBMUD) and above and clearances around struc- the 215-foot service elevation of the Contra tures in high, very high, and ex- Costa County Water District. Fire hazard in treme fire risk areas. (See Figure these areas is amplified by a lack of adequate 7, page 6-13.) water pressure and supply. Thus, fire hazard is of particular concern at the municipal golf Action 4.2.4. Working with the Contra Costa course and in the southeastern areas of Ygna- County Fire Protection District, cio Valley near the ends of Snyder Lane and use nuisance ordinances to re- Hutchinson Road near Northgate Road. duce the risks of dry grasses.
The fire district tries to minimize fire risk through its weed-abatement program, which covers all wildland areas within the County’s jurisdiction. The district also works with Mt. Diablo State Park, which has a State and lo- cally approved fire management plan that co- ordinates among a number of State, regional, and county agencies.
GOAL 4 Strive to prevent and reduce damage related to fire hazards.
Policy 4.1. Regulate projects in high-risk areas. (See Figure 7, page 6-13.)
Policy 4.2. Work with the Contra Costa County Fire Protection District to ensure adequate fire re- sponse times and address other fire-related issues in the Plan- ning Area.
Action 4.2.1. Require that all new develop- ment or redevelopment plans be submitted to the Fire District for review.
Action 4.2.2. Require greenbelt zones and fire-resistant landscaping and
April 4, 2006 Walnut Creek General Plan 2025 6-11 Chapter 6, Safety and Noise
Concord Pleasant Hill
Station Number 10
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Rudgear Rd
Tic e V alle y B lvd Station Number 3
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Fire Stations
Fire Station Service Area (1 mile radius)
Highways
Major Roads
City Limit
Alamo Planning Area Boundary
Note: Station radii depicting response areas are shown for Miles general reference only. Actual response times measured 00.511.520.25 by roadway length. Refer to text for further discussion. Base Map Data: January 16, 2004
Figure 6. Fire Stations and Fire Service Areas in Walnut Creek
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Concord Pleasant Hill
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Rudgear Rd
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I - 6 8 R 0 o s s m o o r P k w y Threat to People From Wildland Fire Moderate
High
Very High
Extreme Alamo Highways Major Roads Planning Area Boundary
Miles 00.511.520.25 Base Map Data: January 16, 2004 Note: See text for further explanation of threat categories. Source Data: Department of Forestry and Fire Protection, 2003 Figure 7. Wildland-Urban Interface Fire Threat
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GOAL 5 Promote public safety. PUBLIC SAFETY A five-year strategic plan sets forth the Police Policy 5.1. Address school safety, in par- Department’s approach to providing for public ticular related to providing safety. The plan, first prepared in 1973, has emergency access to schools evolved over the years to critically examine during school hours. police operations in relation to community needs. Policy 5.2. Maintain a response time of less than 5 minutes for emer- The nature of policing in the community must gency calls and for other calls be responsive to the dynamics of the commu- less than 20 minutes, 95 per- nity, such as changes in population demo- cent of the time. graphics (e.g., a higher concentration of sen- iors in the community), increases in traffic, Policy 5.3. Support Community Oriented commercial growth, new types of social and Policing. recreational activities, and a greater number of late-night downtown dining and entertain- Policy 5.4. Cooperate with the County on ment venues and events. The challenge is to public safety and policing is- remain alert to changes that influence po- sues outside the city limits. lice/community communications and crime- prevention efforts. Policy 5.5. Seek ways to reduce police service demands through pro- ject design enhancements.
Action 5.5.1. Incorporate crime-reduction and public-safety features in the design and planning of private and public projects.
Action 5.5.2. Submit all discretionary permits to the Police Department for analysis of and recommenda- tions to reduce impacts on po- lice services.
Traffic patrol leaves from police garage
The City’s Community Policing Team (COP) provides services for quality-of-life issues, in- cluding crime prevention, alarm monitoring and response, and school liaison and classes. In 2005, the team had five members.
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DISASTER RESPONSE The second phase (response) emphasizes re- ducing the effects of an emergency or disaster. Local, state, and federal governments share This phase involves both pre-emergency and responsibility for preserving life and safety. emergency activities. The City of Walnut Creek has prepared an Emergency Operation Plan (EOP) that identi- Pre-emergency activities include the following: fies and allocates resources in response to emergencies, from preparation through recov- • Evacuations ery. The EOP identifies the City’s emergency • planning, organizational, and response poli- Requests for mutual aid cies and procedures and how they will be co- • Proclamation of an emergency ordinated with emergency responses from other levels of government. Emergency activities encompass actions that save lives and property, control the emergency situation, or minimize the impacts of the disas- ter. Activities include:
• Rescue operations • Treating the injured • Restricting and/or directing the movement of people and traffic • Preparing detailed damage assess- ments
• Operating mass care facilities John Muir Medical Center is a critical facility • Coroner operations • Walnut Creek’s EOP unfolds in three phases: Providing information to the public 1) readiness, 2) response, and 3) recovery. Third phase (recovery) activities focus on post- Events that may trigger phase one (readiness) disaster rebuilding efforts, such as the follow- include the following: ing: • Hazard mitigation • Credible earthquake predictions • Identification of residual hazards • Flood or special weather advisories • Restoration of essential services • Potential dam failure advisories • Application for State or federal assis- • Red flag (high fire danger) warnings tance • Hazardous materials incidents The ability to respond to emergencies de- • Information indicating a high potential pends, in large part, on the area’s critical facili- for violence, terrorism, or civil distur- ties—facilities that house emergency respond- bance ers and those that provide emergency services. They include hospitals, fire stations, police and emergency services facilities, and utility and communications facilities and transmission lines.
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GOAL 6 WATER SUPPLY Two water districts supply Walnut Creek’s Provide quick response to water: The Contra Costa Water District disasters. (CCWD) and the East Bay Municipal District (EBMUD). All water distribution and treat- Policy 6.1. In the event of a disaster, strive ment facilities within Walnut Creek are owned to reduce injury, loss of life, and operated by EBMUD or CCWD. and property damage.
Action 6.1.1. Prepare and adopt a list and map of evacuation routes. GOAL 7 Action 6.1.2. Regularly review and update Work with the water districts the Emergency Operations Plan. to ensure safe and adequate water supplies for the Plan- Policy 6.1.3. Following a disaster, require the ning Area. screening of debris for hazard- ous materials before allowing reuse or recycling. Policy 7.1. Work with water agencies to secure water supplies to serve Policy 6.2. Safeguard the city’s critical fa- the Planning Area’s growing cilities and make any repairs number of residents and em- as quickly as possible. ployees.
Action 6.2.1. Include a map of critical facili- Action 7.1.1. Work with water agencies and ties in the Emergency Opera- the fire district to ensure the tions Plan. availability of an adequate wa- ter supply, particularly during peakload periods, to serve fire- fighting needs.
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NOISE BART tracks. Noise resulting from BART trains is intermittent and has a unique character that is easily distinguishable from other traffic State law mandates that the general plan have noise. a noise element that identifies noise sources in the planning area and strategies for reducing Along local routes of regional significance any negative impacts from noise on the com- (e.g., Treat Boulevard and Ygnacio Valley munity. Road) and arterials such as Mt. Diablo Boule- vard, roadside noise levels range from 72 Ldn to as high as 75 Ldn. Along arterials such as WHAT IS NOISE? Broadway and Walnut Avenue and along most of the city’s major and minor streets, the Noise is unwanted sound. Excessive noise can measured noise level ranges from 60 Ldn to 70 cause hearing loss and interfere with human Ldn. activity. It can disrupt communication and af- fect a person’s performance. Away from streets carrying substantial through traffic, Walnut Creek remains quiet. Which sounds are considered noise is subjec- tive and varies from person to person and with Parking lot maintenance generates noise. Be- the time of day and setting. cause parking demand is high in many of the city’s business and commercial districts, park- Sensitivity to noise increases in the evening ing facilities must maintained during off-peak and at night. Excessive noise interferes with hours. Commercial parking areas near residen- the ability to sleep, so 24-hour descriptors tial areas create a conflict between the need to were developed to add artificial noise penal- maintain parking facilities and pick up trash, ties to quiet-time noise events. State law re- and the demand for residential quiet. quires general plans to use the Community Noise Equivalent Level (CNEL) or the The Municipal Code, Title 4, Article 2, ad- Day/Night Average Sound Level (Ldn) to de- dresses excessive, unreasonable, and pro- scribe the community noise environment and longed noise, including the use of amplified its effects on the population. The two are es- sound, building construction and repair, and sentially the same. General Plan 2025 uses Ldn. noise from leaf blowers. (See Figure 8, Land Use/Noise Compatibility, page 6-19.) Goal 9 and its policies and actions aim to con- trol noise in existing residential areas by not allowing noise levels to increase substantially, THE URBAN NOISE regardless of the absolute noise level. ENVIRONMENT Noise measurements conducted in Walnut Creek as part of General Plan 2025 reflect a va- riety of noise environments. The loudest noise source is Interstate 680. In a typical location 250 feet from the center of the highway, the Ldn was 75 dBA. At or near the freeway, the noise level ranged from 78 Ldn to 80 Ldn.
BART generates a noise level of 66 Ldn , as measured along Minert Street, 80 feet from the
April 4, 2006 Walnut Creek General Plan 2025 6-17 Chapter 6, Safety and Noise
GOAL 8 dential development affected by noise from BART or helicopters, Provide compatible noise ensure that maximum noise environments for new levels do not exceed 50 Ldn in development, redevelop- bedrooms and 55 Ldn in other ment, and condominium rooms. conversions. Action 8.2.5. Establish single-event noise standards for new downtown Policy 8.1. Apply the noise and land use mixed-use development or for compatibility table and stan- new residential development dards to all residential, com- affected by noise from BART or mercial, and mixed-use pro- helicopters. posals, including condomin- ium conversions. GOAL 9 Policy 8.2. Address the issue of residences affected by intermittent urban Control excessive noise noise from sources such as sources in existing heating, ventilating, and air development. conditioning equipment and by outdoor maintenance activi- ties, such as parking lot sweep- Policy 9.1. Control all residential and ing and early morning garbage commercial noise sources to collection. protect the existing noise envi- ronment. Action 8.2.1. For new single-family residen- tial projects, use a standard of Action 9.1.1. Require the evaluation of noise mitigation measures for projects 60 Ldn for exterior noise in pri- vate use areas. that would cause a substantial increase in noise. Action 8.2.2. For new multifamily residential projects and for the residential Policy 9.2. Strive to reduce traffic noise component of mixed-use devel- levels in existing residential opment, use a standard of 65 areas. Ldn in outdoor areas, excluding balconies. Action 9.2.1. Install quiet pavement surfaces for repaving projects, where Action 8.2.3. Strive for a maximum interior feasible. noise levels at 45 Ldn in all new residential units. Action 9.2.2. Control vehicle-related noise.
Action 8.2.4. For new downtown mixed-use development or for new resi-
6-18 Walnut Creek General Plan 2025 April 4, 2006 Figure 8. Land Use/Noise Compatibility
EXTERIOR NOISE EXPOSURE LAND USE (LDN) CATEGORY 55 60 65 70 75 80
Single-family residential
Multifamily residential, hotels, and motels See footnote(a)
Outdoor sports and recreation, neighborhood parks and playgrounds
Schools, libraries, museums, hospitals, personal care, meeting halls, churches
Office buildings, business commercial, and professional
Auditoriums, concert halls, amphi- theaters
(a) Require noise mitigation to reduce interior noise levels pursuant to Actions 8.2.3. and 8.2.4.
NORMALLY ACCEPTABLE Specified land use is satisfactory, based on the as- sumption that any buildings involved are of normal conventional construction, without any special insulation requirements.
CONDITIONALLY ACCEPTABLE Specified land use may be permitted only af- ter detailed analysis of the noise reduction requirements.
UNACCEPTABLE New construction or development should not be undertaken because mitigation to comply with noise element policies is unfeasible.
Source: General Plan Guidelines, Office of Planning and Research, Appendix C, Noise Element Guide- lines; 2003 and Illingworth & Rodkin.
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