The City of San Diego maintains 84 miles of concrete and dirt drainage channels and ditches that are designed to handle water flow from storm drains and canyon runoff and "channel" the water into the bay or ocean. There are also numerous miles of privately owned and maintained channels and ditches within the City. The Storm Water Department conducts regular inspections and performs cleaning as needed. We encourage the public to notify us when a channel or ditch is blocked or filled with debris. This will help minimize the possibility of flooding and help improve water quality.
Information about maintenance of the City's channels and ditches can be found at the Routine Channel Maintenance Activities web page.
The purpose of this work is to maintain existing storm water facilities by restoring their original design capacity to provide public safety and protection of property. The City must routinely maintain the drainage channels through periodic removal of trash, debris, vegetation and accumulated sediment.
Prior to any maintenance activity, detailed hydrological, biological and cultural studies are conducted to identify where maintenance is needed, the best method to conduct needed maintenance, and the specific maintenance protocols that will be used to protect water quality and natural resources. A detailed Individual Hydrologic and Hydraulic Assessment (IHHA) is performed to determine the design flood conveyance capacity of the facility, its current conveyance capacity, the sources and quantity of obstruction (e.g. accumulation of sediment and/or vegetation), the quantity of materials to be removed, the method of removal and the amount of flood conveyance that will be achieved after maintenance.
An Individual Biological Assessment (IBA) is conducted to quantify the types of vegetation present in the facility and the presence of, and the potential for that vegetation to support threatened or endangered species. The IBA also identifies the mitigation measures needed to ensure that the maintenance does not affect natural resources. Individual Historic Assessment (IHA) surveys are conducted to identify the presence of archaeological resources and the potential of the facility to support cultural resources, and identify mitigation measures needed to ensure that cultural resources are not affected.
Based on the specific results of the hydrological, biological and cultural studies, the Storm Water Division creates an Individual Maintenance Plan (IMP) that identifies the maintenance method(s) to be used, equipment type, appropriate Best Management Practices (BMP), access locations, staging areas, spoils storage sites, and schedule. In addition, the IMP incorporates relevant maintenance protocols as well as specific mitigation measures identified in the IHHA, IBA and IHA for the activity.
Rainy Season Emergency Preparations
Each year, in advance of our rainy season, our operations and maintenance teams inspect the entire system of storm drains and channels throughout the City. Those teams help create the list of priorities for maintenance and replacement efforts and keep track of areas that may pose problems during heavy rains. The City has an active "storm patrol" ready to respond to problems during wet weather. Click the link below to learn more about our emergency planning efforts and about our maintenance selection process.