Portola Municipal Code Ch. 16.16 Improvement Standards

In all cases, materials used, preparation of base, methods of placing materials, workmanship, grading and tests of materials shall not be less than those standards required by the most recent Standard Specifications of the state of California, Department of Public Works, Division of Highways, except where special provisions are required.

(Ord. 146 § 3.2(a), 1975)

A. The roadbed shall be designed according to soil tests of the subgrade material and such design shall be based on "R" value of the subgrade and base material together with the application of the appropriate traffic index applying to the particular class of street as established by the standard details, and in accordance with the standard procedure of the California Division of Highways in the design of roads under their jurisdiction or by such other method as is in general use and considered sound practice.

B. There shall be a minimum of two inches of hot plant mix surfacing, with a sand seal coat.

(Ord. 146 § 3.2(b), 1975)

Sidewalks, curbs and gutters shall be constructed of Class A concrete. Curb treatment at driveway entrances shall be constructed in accordance with standard details.

(Ord. 146 § 3.2(c), 1975)

Required fill shall be of suitable filling material and placed in such a manner as to insure that the finished elevation of all lots and roadway areas will be adequate to protect the subdivision from floods and there shall be adequate provision for the passage of storm water runoff after settlement and compaction. No building or construction on filled land shall be commenced until satisfactory evidence has been submitted that the required elevation has been obtained and that the fill will provide a stable base for the construction proposed. Such evidence of satisfactory fill shall be submitted to the city engineer and the approval for construction of improvements upon said fill shall be granted by the city engineer.

(Ord. 146 § 3.2(d), 1975)

Provisions for drainage and flood control shall be established on the following basis:

A. Major drainage channels or conduits are those which have a drainage area of two square miles or more and shall have sufficient capacity to contain the highest known runoff based on a one hundred-year rainfall experience.

B. Secondary drainage channels or conduits are those which have a drainage area of less than two square miles and more than ten acres, and shall have sufficient capacity to contain the highest known runoff based on a fifty-year rainfall experience.

C. Minor drainage channels, conduits and inlet facilities are those which have a drainage area of ten acres or less, and shall have sufficient capacity to contain the highest known runoff based on a twenty-five-year rainfall experience.

D. Design of drainage and flood control works, structures, channels, conduits, pondage, etc., shall conform with good engineering practice.

(Ord. 146 § 3.2(e), 1975)