3.0 Circulation
The urbanized portion of the study area generally has an adequate system of public roads, with a few exceptions; however, the hillside planning area is characterized by an inadequate discontinuous road network. Residential development in the hillside area is limited by the difficulty of access. Generally, the roads in the hillside area are characterized by inadequate width, steep grades, excessive lengths, poor surfacing, little or no shoulder development, and steep cut banks. Many roads come to a deadend, with no alternate way out in case of fire.
The remote southeastern portion of the area is inaccessible from existing roads. The steep terrain makes road building extremely costly, and unless it is based upon careful and unique design and engineering standards, hillside road building can cause ugly scarring of the landscape. In the past, roadway design has not taken into account the difficult terrain features and geologic hazards of the hillside area. Another problem in the hillside area is the undefined status of maintenance responsibility for roadways; numerous roads are private with little or no maintenance being performed. There have been and continue to be differences between the County and Town in design standards, ownership, and timing of construction of full street improvements. The Hillside Committee found a lack of safe and adequate road access in much of the hillside area and a definite need for development of a road network subject to the physical limitations of the area, and the desires of the residents.
Mountain roads are very costly to police, maintain and to clean up after landslides or storms. Maintenance of services for each hillside residence costs more than for a flatland residence.
3.2 Goals
Provision for vehicular traffic in harmony with the topography and ecology of the area.
3.3 Policies
1. Design of Hillside Roads and Driveways:
a. Hillside roadways and driveways shall be designed and located so as to:
1. Require a minimum amount of earth movement.
2. Be consistent with the specified standards for curves, gradients, widths, and other controlling factors.
3. Be in harmony with the surrounding landscape by utilizing aesthetic design concepts, including landscaping with native plants and materials.
4. Allow for special designs where natural features such as rocks, slopes and trees require special treatment.
b. Adequate slope easements shall be provided.
2. Private Roads Versus Public Roads:
a. An adequate system of publicly owned and maintained roads is the best means of providing adequate access to all properties. Access by private road shall not be allowed unless fundamental to a special approved design concept unless full provisions for construction and maintenance of the private road system have been approved and unless it is consistent with neighborhood circulation.
b. A private access road to Guadalupe College from the Lexington Reservoir area will be provided from Alma Bridge Road/Limekiln Road. The private access road shall incorporate provisions for emergency access to Foster Road.
3. Separate Road Improvement Standards for MajorSubdivisions and Minor Subdivisions:
In this plan there is no distinction between major and minor subdivisions with regard to road improvement standards.
4. Roadway Design:
a. Special roadway design standards shall be utilized in the development of hillside roadways considering the purpose of the roads.
b. Roadway design techniques such as split-level roadbed should be utilized in order to reduce the "scarring" of hillsides.
c. Increased number of on-site parking spaces shall be provided in lieu of those spaces on the roadway which are eliminated by use of hillside street standards.
5. Mountain Collector Streets:
Collector streets, as defined in the Town General Plan, should be connected to other public streets to provide a basic roadway network of alternate routes, without providing attractive through routes to non-local traffic. Town's General Plan defines a collector street as a street that serves abutting property and carries traffic to the arterials and expressways.
6. Two Means of Access:
a. As a guide to developing a circulation plan, two means of access shall be provided to all areas. If dual access is NOT available, the land use intensity shall be limited in accordance with the access provided.
b. Secondary access shall be sought for existing dead end streets.
c. The second means of access shall not encourage through traffic to nonresidents and could be limited to emergency access only.
d. Where single access roads exist, acceptable provisions shall be made for emergency access. Emergency access roads shall be designed to assure passability, however, the design shall prevent unauthorized non-emergency through access.
7. Road Costs:
The developer shall pay all costs for all required street improvements.
3.4 Implementation
8. Cul-de-sacs:
Cul-de-sacs should not exceed 800 feet in length, although the length may be increased by the deciding body if it finds that alternative solutions to emergency access, utility services and circulation problems are satisfactory.
9. Road Widths:
Because of unique problems encountered in development of hillside areas, the following standards are recommended for the roads of study area:
a. Flatland standards:
Right-of-way width 60'
Cul-de-sac right-of-way width 56'
Paved width 40'
Cul-de-sac paved width 36'
b. Hillside standards:*
Right-of-way width 60-40' minimum**
Paved way widths:
One-way 14'
Cul-de-sac 20'***
Cul-de-sac 24'
Local 24'
Collector 28'-30'****
For specific design roads, the width is to be determined as constrained by terrain and major trees.
** County minimum width to be 60'. Town right-of-way width to be 40' for standard two-lane roads and slope easements shall be provided where necessary and as necessary for slope banks.
*** Cul-de-sac with a potential of six lots or less.
**** County Standards.
10. Maximum Road Grade, Minimum Curve Radius, and Overhead Clearance:
Maximum road grade, minimum curve radius and overhead clearance should be determined by the Road Commissioner, Town Engineer or County Surveyor with advice and recommendation from other appropriate Town or County departments or agencies (e.g. Planning Department, Parks Department, Central Fire District, etc.). Deviation from these standards may be permitted only with special approval when it can be demonstrated that significant environmental damage would result from strict adherence.
11. Parking/Turnouts on Roadways:
a. Provisions have not been made for parking on roadways under the Hillside standard; if parking on roadways is required for a specific project, it should be provided by parking turnouts.
b. Turnouts should be provided in accordance with requirements for Central Fire District and for viewpoints on scenic roads.
12. Curbs:
Curbs should be used along both sides of all roads to minimize maintenance costs, control erosion and provide for additional public safety.
13. Pavement Surfacing:
The pavement surfacing for public and private roads should be asphaltic concrete or Portland cement concrete.
14. Walkways:
Improved pathways or walkways should normally be required in the approval of land developments.
Their specific location and relationship to the roadway should be subject to approval by the deciding body; in some cases, the walkway may be separated from the roadway where warranted by topographic conditions.
15. On-Site Parking and Turnaround Areas:
Parking and maneuvering areas for emergency vehicles should be provided as required by the Central Fire District. In addition to those parking spaces in garages or carports, not less than four on-site parking spaces shall be provided where roadways are not designed to permit parking. Driveways may be used to provide this parking, except where all or a substantial part of any residence is in excess of one hundred fifty (150) feet from a safe and adequate access road.
16. Proof of Access Rights:
Documentation of proof of private access rights must be provided by the developer at the initial project review stage.
17. Driveway Standards (width, length, gradient, minimum curve radius):
Driveways serving one residence should have 12-foot minimum width plus 3 feet of shoulder width (15 feet total); however, the deciding body may determine that an 18-foot minimum width is necessary. A common driveway serving two single-family residences should have an 18-foot minimum width plus 3-foot shoulders on each side. This requirement may be reduced to 18-foot minimum if the Town Engineer or County Surveyor determines that the shoulders could be replaced with retaining walls and curbs. Limit of driveway length should be 300 feet unless the deciding body can make specific findings for deviation and can place additional conditions to reduce hazards such as turnouts and secondary accesses. Other standards regarding length, grades, and minimum curve radius are to be determined by the Town Engineer or County Surveyor with advice and recommendation from other appropriate Town or County departments. No more than two dwelling units should be served from a common driveway.
18. Access Roads:
Access roads as used herein are defined as roads connecting a parcel of land being considered for development to the nearest improved public road. Access roads shall meet the following development standards:
Dwelling Units Pavement Shoulder Pavement
Served Width (Each) Surface
2-3 18' 3' AC
4-6 20' 3' AC
7 or more 24' 3' AC
19. Public Transportation:
Any intensive non-residential use shall provide common carrier vehicle service with direct connection to a countywide transit facility.
20. Roadway Landscaping:
Roadway and driveway graded banks shall be provided with planting of native trees, shrubs, and grasses, and include irrigation devices to ensure maintenance of landscaping until it is permanently established.
21. Emergency Access Roads:
Emergency access roads shall be provided in accordance with the following standards:
a. Standards:
1. Right-of-way
Right-of-way shall be an emergency access easement granted to the public. Some consideration of pedestrian trail easements should also be included.
2. Width
The width of the easement should be sufficient to contain the roadway with whatever additional easements are necessary for slope banks in the case of steep terrain. Roadbed widths should be a minimum of 15 feet plus an additional three feet of shoulder. A lesser width may not be approved unless there is a finding by the Planning Commission that the minimum width called for above would have a severe environmental impact, and that with a lesser width adequate fire protection can be maintained.
3. Structural Strength
Structural strength of the roadbed shall be designed to withstand a gross vehicle weight of 30,000 pounds. A minimum of six inches of aggregate base and some surface sufficient to protect the base shall be required.
4. Roadway Surface
Roadway surface must be sufficient to protect the roadway base and provide a non-skid surface in areas where the grade exceeds 15%. Where the grade is less than 15% the surface shall be a double chip seal.
5. Closure Devices
Gates with locking devices shall provide closure and permit access by Police, Fire and other emergency vehicles, maintenance vehicles and by the general public in times of emergency. Staff shall conduct a study of gates and appropriate locking mechanisms in order to resolve the following and other problems, and submit its report to the Planning Commission meeting at its second meeting in January, 1985:
a) Making operation easy enough to facilitate inspection, maintenance and quick access during emergencies. Ideally, an Operator or Inspector should be able to open the gate without leaving the vehicle.
b) Reducing vandalism.
c) Preventing access by motorcycles.
d) Providing operational effectiveness under emergency conditions.
b. Inspection:
Inspection shall occur at three month intervals to ensure that the emergency access road is adequately maintained to serve its intended purpose and to ensure that it has not been blocked by unauthorized storage of construction materials, inoperative vehicles, slides, trees, etc.
c. Inventory:
A thorough inventory shall be made to clearly identify all emergency access roads to determine what deficiencies and limitations exist for their use so that emergency response plans can be made. Any changes in the inventory shall be documented as they occur. A report on the inventory shall be submitted to the Planning Commission at its second meeting in January, 1985.
d. Maintenance:
Developers of land who create the need for emergency access roads shall dedicate the necessary right-of-way and enter into perpetual agreements with the Town, tying responsibility for maintenance of emergency access roadways and locking devices to the land.
e. Complaints:
Complaints of problems with emergency access roads or locking devices shall be investigated promptly by Town Staff.