Laguna Hills Municipal Code Art. XIII Erosion Control

A. The faces of cut and fill slopes and project site shall be prepared and maintained to control against erosion in accordance with this article. Where cut slopes are not subject to erosion due to the erosion-resistant character of the materials, such protection may be omitted upon approval by the Director.

B. Where necessary, temporary and/or permanent erosion control devices such as desilting basins, check dams, riprap, or other devices or methods, as approved by the Director, shall be employed to control erosion and provide safety during the rainy season from October 15th to April 15th.

C. No grading work in excess of two hundred (200) cubic yards will be allowed between October 15th and April 15th on any single grading site under permit unless an erosion control system has been approved or waived by the Director.

D. Paved streets, sidewalks, and other improvements shall be maintained in a neat and clean condition free of loose soil, construction debris, and trash. Street sweeping or other equally effective means shall be used on a regular basis to prevent storm flows from carrying sediment and debris outside the project boundaries. Watering shall not be used to clean streets except for fine material not otherwise removed by sweeping or other mechanical means.

E. Unless otherwise approved by the Director, the owner shall be required to retain a civil engineer who will be responsible for the design of all erosion control improvements and initial approval of the installation of permanent and semi-permanent erosion control devices during each rainy season until the work authorized by the grading permit is given final approval. The owner shall retain the civil engineer to periodically review the field condition and modify, as needed, the design of the permanent and semi-permanent erosion control devices during the rainy season. Installation and maintenance of all erosion control devices shall be the responsibility of the owner.

F. Desilting facilities shall be provided at drainage outlets from the graded site.

G. Desilting basins shall be designed to provide a minimum desilting capacity equal to the standards established by this code.

H. Desilting basins shall be constructed around the perimeter of projects whenever feasible when it provides improved maintenance access from paved roads during wet weather.

I. Desilting basins constructed of compacted earth shall be compacted to a relative compaction on ninety (90) percent of maximum density. A soil engineering report, prepared by the soil engineer, which includes the type of field testing performed, location, and results of testing shall be submitted to the Director for approval upon completion of the desilting basins.

J. Equipment and workers for emergency work shall be made available at all times during the rainy season. Necessary materials shall be available on-site and stockpiled at convenient locations to facilitate rapid construction of temporary devices when rain is imminent.

K. Erosion protection shall consist of effective planting of all slopes in excess of five feet high unless otherwise approved by the Director. Slopes exceeding fifteen (15) feet high may require an adequate sprinkler system, as determined by the Director.

Protection for the slopes shall be installed as soon as practicable which may be prior to rough grade approval. Effective planting shall be installed, fully germinated, and effectively cover the required slopes prior to final approval unless otherwise approved by the Director.

L. The erosion control provisions shall take into account drainage patterns during the current and future phases of grading throughout the rainy season.

M. All removable protective devices shown shall be in place at the end of each working day when the fiveday rain probability forecast exceeds forty (40) percent.

N. Graded areas around the tract perimeter must drain away from the face of slopes at the conclusion of each working day.

O. In addition to the requirements specified above, the permittee shall perform all work in accordance with the water quality requirements.

P. Any violation of an applicable federal or state-issued storm water permit, or failure to conform to the city’s water quality requirements prepared pursuant to such a permit or pursuant to this chapter or to section 5-36.010 et seq.; or failure to comply with stormwater related provisions of a city-issued grading permit or of a grading plan prepared to secure such a permit, is also a violation of this chapter.

(Ord. 03-1 § 1 (part))

Erosion control plans prepared in accordance with Subarticle 13 of the Grading Manual shall be submitted to the Director for approval by September 15th each year for projects under grading permit. The erosion control plan may be waived for grading projects on single residential lot projects providing that an erosion control system, meeting the approval of the Director, has been installed, placed, planted, or constructed before October 15th.

(Ord. 03-1 § 1 (part))

A. After each rainstorm, silt and debris shall be removed from check berms and desilting basins and the basins pumped dry.

B. After each rainstorm, the performance of the erosion control system shall be evaluated and revised and repaired as necessary.

C. Devices shall not be moved or modified without the approval of the Director.

D. The grading contractor shall be responsible and shall take necessary precautions to prevent public trespass onto areas where impounded water creates a hazardous condition.

E. The grading contractor and permittee or project owner shall be responsible for continual maintenance of the devices during the rainy season. In the event of failure or refusal by the contractor, permittee, or project owner to properly maintain the devices, the Director may cause emergency maintenance work to be done to protect adjacent private and public property and environmental resources. The cost shall be charged to the owner and shall include an initial mobilization cost plus the cost of doing the work as contained in Article VI of this code.

F. In the event the Director must cause emergency maintenance work to be done, he or she may revoke the grading permit in writing. The grading permit shall not be renewed until an erosion control system and/or other systems necessary to comply with water quality requirements approved by the Director are installed and a fee of one-half the amount required for the original grading permit paid by the owner. The Director may waive installation of an erosion control system after April 15th.

G. If any grading subject to Section 10-16.060, Grading permits, of this code has commenced on private property without a valid grading permit, the property owner may be required to prepare and implement an erosion control plan as well as other plans required under the water quality requirements, which have been approved by the Director. In the event of failure by the property owner to install an approved erosion control system and/or other systems necessary to comply with water quality requirements, the Director may cause emergency work to be done to protect adjacent private and public property. The procedures of Section 10-16.130, Hazardous conditions, of this code need not apply for emergency erosion control work between October 15th and April 15th and emergency work necessary to protect environmental resources. The cost shall be charged to the owner in accordance with subsection E of this section.

(Ord. 03-1 § 1 (part))