The erosion and sediment control plans shall be prepared by a person or firm qualified by training and experience to have expert knowledge of runoff, erosion, and sediment control treatments, including drainage and related land conservation techniques.
The plans shall contain appropriate information according to this article.
(§ 1, Ord. 601, eff. May 13, 1982)
The erosion and sediment control plans shall include the following:
(a) 
Native vegetation.
(1) 
Descriptions of the native vegetation;
(2) 
The location of native vegetation whose root zone will be affected by compaction, fills, trenches, and changes in the groundwater table;
(3) 
A list of the vegetation to be removed and the criteria used to determine removal;
(4) 
When the vegetation shall be removed; the method shall be one which will minimize the erosive effects from the removal;
(5) 
Measures which will prevent conditions damaging to vegetation shall be specified;
(6) 
In no event shall the native vegetation ground cover be destroyed, removed, or disturbed more than 15 days prior to grading unless otherwise approved by the City. Exposure of soil to erosion by removing vegetation shall be limited to the area required for immediate construction operations; and
(7) 
Native vegetation shall be retained, protected, and supplemented wherever possible; and
(b) 
Establishment of vegetation. Where the establishment of vegetation is required on slopes of cut and fill, graded areas, and watercourses, the following information shall be provided on the plan:
(1) 
The location and area to be vegetated;
(2) 
An indication of whether the vegetation is temporary or permanent;
(3) 
The type and quantity of seeds or plants;
(4) 
The ground conditions as follows:
(i) 
The surface condition of the soil;
(ii) 
The permeability;
(iii) 
The slope angle, slope length, and aspect; and
(iv) 
The nutrients in the soil;
(5) 
The type and quantity of mulch;
(6) 
The type and quantity of fertilizer;
(7) 
The method and schedule of seeding, mulching, planting, and fertilizing; and
(8) 
The method and schedule of irrigation.
(§ 1, Ord. 601, eff. May 13, 1982)
Where it is necessary to reduce the increased rate and volume of rainfall runoff due to the alteration of the runoff pattern, the following data shall be provided:
(a) 
The runoff rate and volume to be expected from a 10 year 24 hour frequency rainstorm for conditions existing before and after the proposed land disturbance;
(b) 
The location of natural and man-made drainageways;
(c) 
The size of the drainage areas above the cuts and slopes;
(d) 
The methods to be used to reduce the erosion of drainageways;
(e) 
The procedures used to trap sediment in order to protect drainage control facilities;
(f) 
The methods used to prevent or control the rate and direction of runoff on roadways during and after land disturbances;
(g) 
The methods used to control runoff across the slopes of cuts and fills and graded areas during and after land disturbances;
(h) 
The schedule for the construction of drainage protection and control measures; and
(i) 
The method and schedule for the construction of waterway crossings.
(§ 1, Ord. 601, eff. May 13, 1982)
Information on the design criteria of sediment basins shall include the following:
(a) 
The location and dimensions of the sediment basins;
(b) 
The hydrologic and sediment transport data used to determine the proper capacity of the needed basin;
(c) 
The construction schedule and procedure;
(d) 
The source of borrow materials;
(e) 
The type and manner of vegetating the erodible slopes; and
(f) 
A maintenance schedule demonstrating firm and fixed periods for the removal of debris and sediment and repairs to structures. The schedule and the facility will be subject to annual review by the City Engineer for compliance.
(§ 1, Ord. 601, eff. May 13, 1982)
The following shall apply to the control of runoff:
(a) 
Provisions shall be made to control the increased runoff caused by changed soil and surface conditions during and after development so that there will be no increase in runoff and sediment over the predevelopment condition.
(b) 
To prevent excess runoff, the rate of surface water runoff shall be structurally retarded.
(§ 1, Ord. 601, eff. May 13, 1982)
An applicant requesting permission to make any surface change shall:
(a) 
Collect on-site surface runoff and dispose of it at non-erosive velocities to the point of discharge into the common natural watercourse of the drainage area;
(b) 
Handle existing and potential off-site runoff through the proposed development by designing the proposed development to adequately handle storm runoff from a fully developed area upstream;
(c) 
Pay his proportionate share of the total cost of off-site drainage control improvements to the common natural watercourse based upon a fully developed drainage area (pursuant to Section 9-10.06 of Chapter 10 of this title);
(d) 
Provide and install, at his expense, all drainage, erosion, and sediment control works (permanent and temporary);
(e) 
Retain sediment being transported by runoff water on-site through the use of sediment basins, silt traps, or similar measures; and
(f) 
Dispose of accumulated sediment during dry seasons to maintain the basin capacity.
(§ 1, Ord. 601, eff. May 13, 1982)
In order to prevent polluting discharges from occurring, approved erosion and sediment control devices shall be required for all grading and filling. Control devices and measures which may be required include, but shall not be limited to, the following:
(a) 
Energy absorbing devices to reduce the velocity of runoff water;
(b) 
Sedimentation controls, such as sediment debris basins and sediment traps. Any trapped sediment shall be removed to a disposal site approved by the City Engineer;
(c) 
The dispersal of water runoff from developed areas over large undisturbed areas; and
(d) 
Multiple discharge points to reduce the volume of runoff over localized areas.
(§ 1, Ord. 601, eff. May 13, 1982)
Where fill slopes are to be constructed, the following information shall be included:
(a) 
The location of the fill area;
(b) 
The slope and height of the fill;
(c) 
The slope and condition of the original ground;
(d) 
The number and dimensions of benches;
(e) 
The source of fill material;
(f) 
The ability of the fill to support vegetation;
(g) 
The methods of protecting the slope surface of the fill;
(h) 
The number and width of the drainage terraces to be installed;
(i) 
Fills shall not encroach on natural watercourses or constructed channels; and
(j) 
Fills placed against watercourses shall have suitable protection against erosion during flooding.
(§ 1, Ord. 601, eff. May 13, 1982)
Where slopes are to be formed from cuts, the following information shall be included:
(a) 
The location of the cuts;
(b) 
The slope and height of the cuts;
(c) 
The identification of the cuts to be vegetated or not subject to erosion;
(d) 
The number and width of the drainage terraces provided; and
(e) 
The ability of the ground to support vegetation.
(§ 1, Ord. 601, eff. May 13, 1982)
The following shall apply to slope construction:
(a) 
Slopes, both cut and fill, shall not be steeper than two to one (2:1), unless a thorough geological and engineering analysis indicates that steeper slopes are safe and erosion control measures are specified.
(b) 
Slopes shall not be constructed so as to endanger or disturb adjoining property.
(§ 1, Ord. 601, eff. May 13, 1982)
The following shall apply to slope surface stabilization:
(a) 
Temporary mulching, seeding, or other suitable stabilization measures shall be used to protect exposed critical areas during construction or other land disturbances.
(b) 
Earth or paved interceptors and diversions shall be installed at the top of cut or fill slopes where there is a potential for surface runoff.
(c) 
Excavated materials shall not be deposited or stored in or alongside rivers or watercourses where the materials can be washed away by high water or storm runoff.
(§ 1, Ord. 601, eff. May 13, 1982)
Excavated materials removed during grading operations shall be disposed of as follows:
(a) 
By stockpiling all or some of the topsoil on the site for use on areas to be revegetated;
(b) 
By locating stockpiled soil so that, if erosion occurs, it would not become a source for off-site sediment damage;
(c) 
By stockpiling soil far enough from streams or drainageways that surface runoff cannot carry sediment downstream;
(d) 
By stockpiling materials from trenches and pits on the up-slope side of the excavation;
(e) 
By promptly backfilling and compacting stockpiled soil into trenches and pits to reduce the risk of erosion;
(f) 
By applying mulch or other protective coverings on stock-piled material which will be exposed through the winter season or which faces a high risk of intensive summer rains; or
(g) 
By moving excavated materials not to be used at the site to a location approved by the City Manager.
(§ 1, Ord. 601, eff. May 13, 1982)
Vegetation removed during clearing operations shall be disposed of as follows:
(a) 
By clipping all of the cleared vegetation for use as mulch or compost on the site; or
(b) 
By disposing of cleared vegetation by hauling it to an approved sanitary landfill or in a manner and at a location approved by the City Engineer.
(§ 1, Ord. 601, eff. May 13, 1982)