GENERAL CONDITIONS and REQUIREMENTS
At all times, a property owner and a lessee or tenant of any property, through which a natural water course or any channel that may carry storm water runoff passes, shall keep and maintain the water course or channel free from any obstruction that would in any manner prevent or disrupt the flow of water through the water course or channel. If there is any disruption of flow, a Water Course Disruption Permit, issued by BOE, will be required under the following conditions:
- Dam, fill, or obstruct any natural water course or channel that may carry storm water
- Construct, reconstruct, alter, repair, install or maintain any drainage structure in any natural water course or channel that may carry storm water
- Construct, reconstruct, or repair any drainage structure
- Alter, fill, obstruct, or otherwise change any natural water course or channel, or natural drainage channel or course
It will be the responsibility of BOE, using engineering judgement, to determine whether or not a disruption to the water course will take place, including constructing over a water course.
Water Course Disruption Permit Connected to a Grading Permit
BOE would issue ONLY a water course disruption permit if ALL the following apply to the proposed structure, fill, alteration or repair (this would be tied to the Building & Safety Grading Permit for construction):
- Would NOT become part of the City's permanently improved storm water drainage system; AND
- Would NOT interfere with the flow of natural storm water; AND
- Would NOT injure adjoining property
Water Course Disruption Permit Connected to an “A” or “B” Permit
If BOE determines the proposed structure, fill, alteration or repair would become part of the City's permanently improved storm water drainage system, BOE would ALSO require the applicant to apply for a Class “A” permit (primarily for inspection) (LAMC 62.109) or Class "B" permit (LAMC 62.110, 62.111, 62.112).
Some factors which favor the construction of a permanent City storm drain under a B Permit include:
- The construction of a storm drain conduit which is aligned between two improved portions of or extends from an existing City storm drain.
- A major improvement of a watercourse which receive runoff from streets or other public property.
- The choice of an applicant to construct a permanent storm drain under City inspection for possible future acceptance by the City.
Some factors which favor the construction of a private storm drain under a Water Course permit include:
- The construction of drainage facilities in an isolated or unimproved area.
- The improvement of a watercourse which drains private property only.
- Minor repairs, alterations, inlet structures, etc.
Any Water Course Disruption Permit issued by BOE may impose conditions and requirements for its use, and the permit applicant must ensure compliance with all such conditions and requirements. No person shall fail, neglect or refuse to comply with any term or condition contained in any issued permit.
In addition to the Water Course Disruption Permit, the permit engineer may also require the applicant to obtain a Class A (minor improvements that only require inspection) or Class “B” Permit, depending on the required improvements. These permits are required for all construction within a watercourse. Major construction may include driveway bridges, mainline storm drain, debris basins, retention basins construction, or the installation of approved pipe. A “B” Permit may be required whether the proposed storm drain system is to be a private system or become a part of the City’s drainage system.
For construction of a storm drain system that is to become a part of the City’s drainage system, a drainage easement shall be dedicated to the City and construction plans shall be in accordance with City standards and policy. For construction of a drainage system that is to remain ‘private’, City Engineer approved plans may also be required to be prepared, at the discretion of the permit engineer. In such a case, a ‘Waiver of Damages’ may be required.
No structures, drainage devices, or any part thereof shall be constructed in the water course area below a level of two feet above the calculated water surface elevation based upon the Q-50 (clear) flow, or as approved by the permitting engineer. This includes piles, caissons, footings, etc.
In order to provide access for earth moving machinery and the unrestricted flow of debris, except as provided herein this document, no structure shall overhang the watercourse area more than 1/3 of the narrowest reach of the watercourse area width. Overhanging structures shall not extend from both sides of the watercourse area within a single section.
Bridges (driveway or pedestrian) necessary for general legal or emergency access to residences may be constructed over water courses subject to the following additional conditions.
- No bridge shall be constructed without sufficient vertical and horizontal clearance for earth moving machinery to pass beneath it, unless unrestricted access to the watercourse is provided both upstream and downstream of the bridge.
- Driveway Bridges: Width of the bridge shall be limited to the minimum necessary for access, but in no case shall the width exceed 18 feet per Special Order 003-1005.
- Pedestrian Bridges: Width of the bridge shall be limited to the minimum necessary for access, but in no case shall the width exceed ____ .
Other Regulatory Agency Requirements
For properties having water courses, within their boundaries or adjacent to, the applicant shall obtain the necessary permits from outside regulatory agencies. Some of these agencies may include:
- Los Angeles County Department of Public Works
- Regional Water Quality Control Board
- California Department of Fish and Wildlife (CDFW)
- US Army Corps of Engineers
- State of CA CEQA Compliance