By now you’ve certainly heard about the Federal and State regulations aimed at preventing pollution in our creeks, bays, ocean and recreational waters. Some of our routine cleaning activities; such as cleaning sidewalks, patios and other surfaces (i.e. impervious surfaces) often contribute to water pollution. After all, what harm is there in letting a little debris and potable water go down into the gutters? Plenty!

Gutters feed into the storm drain system, which was built for flood control purposes and carrying rainwater away from developed areas. Storm water and all water run-off from outside cleaning practices are not treated like the water in the sewage system – it flows directly into our creeks, bays and ultimately the ocean. This is not just an issue for coastal communities and businesses, but an issue for all of us. Studies show that 90% of water pollution (i.e. polluted creeks, bays and ocean water) is attributed to daily urban activities unrelated to the sewer system.  So you're probably wondering what the City of San Luis Obispo is doing to eliminate stormwater pollution and protect our waterways and ecosystems.  Below is a list of the formal programs that exist within the city to minimize the opportunity for stormwater pollution.

Creek Clean Up

Creek clean-ups are conducted around 10 times per year by City of San Luis Obispo park rangers.  Each year City staff removes roughly 25 tons of trash from open spaces and the riparian zone. This focused effort by our park rangers helps us remove trash from transient encampments, litter, and various other sources of stormwater pollution.  Without this effort, our creeks wouldn't be as beautiful as they are today!

Street Sweeping

Street sweeping helps keep our streets clean and our storm drains clean and clear of leaves, sticks, trash, and other various debris.  Clean storm drains don't get plugged up and they also keep water quality high as it enters our local creeks, and ultimately the ocean. 

To view the street sweeping schedule for your neighborhood please visit our interactive street sweeping map.

Storm Drain Cleaning

The wastewater collections staff conducts all cleaning of storm drain piping and catch basins to help remove unwanted materials prior to it hitting our local creeks.  This program is funded by the Public Works Department but managed through the Utilities Department. Wastewater collections staff is equipped with a vacuum truck and high-powered pressure washing system that allows them to remove unwanted debris from the stormwater collection system.

The Stormwater Collection System consists of inlets, storm mains, manholes, rock guards, grates and other collection points.  The wastewater collection division works in conjunction with the public works department to maintain the stormwater system.  Staff cleans the inlets, mains, and manholes,  as well as inspections on the buried infrastructure, because we have the specialized equipment and expertise to perform these duties.

 The Storm crew cleans inlets and manholes by pressure-washing the structure and vacuuming the debris from the structure.  They have a specialized truck similar to the wastewater combination truck, but higher capacity.  To clean the mains they use a high-pressure nozzle that breaks up debris and drags it back to the manhole or inlet they are working from and the large amounts of debris are vacuumed and trucked to a disposal site..

Storm Drain Inspections

The inspections are performed by two crews depending upon the infrastructure being evaluated.  The storm cleaning crew does visual inspections of the manholes, inlets and some short storm mains.  Some inspections can be performed with a specialized camera called a “quickview” camera, capable of video or capturing still photographs of defects.

Example: http://ww1.prweb.com/prfiles/2010/10/18/4137384/quickview01.jpg

Storm mains which have bends, or are longer in length are inspected by the Collections CCTV camera crew and documented in videos and defects are entered into an inspection program, and documented in CityWorks for future reference.

Storm  Drain Replacement and Maintenance

Storm drain replacement and maintenance is conducted by our Public Works Department.  Making sure that our storm drain infrastructure is adequate to handle heavy rain falls helps ensure that our community does not fall victim to flooding or unwanted contamination.  Streets maintenance staff maintains all storm drain grates and replaces broken or failing storm drain inlets, ensuring that we minimize the opportunity for organic pollutants such as leaves to enter our storm drain system.

Inside of failing CMP pipe where the bottom has corroded and lifted up »  

Once the integrity of the pipe has been compromised, the pipe’s surrounding soil becomes susceptible to piping (soil picked up by flowing water and carried away) and the pipe will eventually collapse.

 « Existing CMP storm pipe removed prior to new construction

Failing storm drain systems are identified by City staff and are typically replaced with polyvinyl chloride (PVC) pipe or High Density Polyethylene (HDPE) pipe.

Installation of new PVC storm drain pipe » 

Integrated Pest Management (IPM)

All city parks are maintained following an Integrated Pest Management (IPM) Program.  This approach endeavors to prevent and remove pests using a variety of measures that minimize stormwater pollution.  The following is a summary of the IPM Program.

Cultural Controls

• Utilizing drip irrigation and micro-spray irrigation systems instead of traditional high volume, high velocity spray heads.
• Perform soil tests every few years at high-use parks to evaluate soil deficiencies which may be leading to an increase of weeds.

Mechanical Controls

• Flail mowing, weed-whipping, hand-pulling and other methods for weed removal other than pesticide-use.
• Install mesh cages prior to new tree plantings to prevent undesirable rodent activity within the root zone.
• Apply heavy mulch (3-4") at tree wells, planter beds, picnic areas to prevent weed growth.
• Use backpack blowers to push grass clippings from walkways, curbs, and gutters back onto the turf.

Physical Control

• Properly prune tree canopies to allow more light and air into the commodity below (i.e. turf, planter, etc.), thus promoting healthier desirable plants that can better compete with and mitigate weeds.  A great example of this is the small lawn to the left of the entrance to the Jack House Gardens, where for years we struggled with poor turf health and weeds due to such a dense canopy overhead that allowed very little sunlight and airflow.
• Conduct routine irrigation audits to prevent overspray caused from faulty or improperly-adjusted heads.

Biological Control

• Maintain a clean owl box at Damon-Garcia (and eventually the future North Broad Street Park) to promote more activity from beneficial predators who assist with rodent control.

Chemical Control

• Recently, the city is incorporating the integration of bare-ground applications of pre-emergent pesticides to mitigate future weeds and reduce the need for post-emergent pesticide applications.
• Currently evaluating the use of multiple different pre- and post-emergent pesticides in order to lessen the potential for weed resistance.
• Incorporation of a more robust fertilization program throughout our sports fields in order to keep desirable plant health high, which in turn will reduce the growth of weeds within the turf.