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Question mark. Frequently Asked Questions
CALL 805-781-7215 for more Information
Click the department links below to scroll to the desired faqs.
 · Water Supply
 · Water Treatment
 · Water   Distribution
 · Meter Reading
 · Conservation
 · Water Reuse
 · Wastewater Collection
 · Pretreatment
 · Water Resource Recovery Facility
Water Supply

Q: What is the City’s source of water?

A: The City of SLO currently receives raw water from five sources; Salinas Reservoir, Whale Rock Reservoir, Nacimiento Reservoir, groundwater (well) and recycled water.

Q: What is the total capacity of source water when both Salinas & Whale Rock reservoirs are full?

A: The Salinas Dam (Santa Margarita Lake) can store 23,843 acre feet and Whale Rock Dam can store 40,600 acre-feet. The City’s share of the Whale Rock Dam total storage is 55.05%, or 22,383 acre feet, which provides a combined total of 46,183 acre feet.

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Water Treatment

Q: Is there Mercury in Nacimiento Water?

A: Click here.

Q: Why is chlorine added to the City of San Luis Obispo’s water?

A: Chlorine is added to treated drinking water as it enters the distribution system from the treatment plant and from the well. A chlorine residual ensures that no bacterial contamination of the water occurs. Chlorine concentrations vary according to the distance from the point of chlorine application. Chlorine residuals in the system range from 0.2 mg/l to 1.2 mg/l depending on the proximity to the treatment plant or well. While chlorine can cause complaints of bad taste, City customers can be assured that the water supply meets and exceeds safe drinking water standards.

Q: Does your water have a distinct taste?

A: The complaints of bad tasting water is typically associated with chlorine. Try placing a pitcher of water in your refrigerator. The Chlorine will dissipate and the colder temperature will enhance the taste of the water.

Q: Why is my water sometimes discolored?

A: Routine hydrant flow tests, system maintenance or water main breaks can result in discolored water. This is caused by a change in direction and velocity of water within the pipes. If this happens, let the water run at your faucet for several minutes until it flows clear. If the problem persists, call Utilities, 781-7215.

Q: Why does my water appear cloudy or “milky” at times?

A: This is often the result of air bubbles in the water. Set the glass of water on the counter, and it should clear after standing for several minutes.

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Water Distribution

Q: Why is our water off?

A: The distribution system occasionally has main line breaks. When this occurs the crews rarely have the opportunity to notify the public. In an emergency shutdown such as this, distribution crews notify the police of the areas that will be affected. For a planned water main shutdown crews give 24hr notices to customers in the area the shutdown will affect.
Report Leak/More Information

Q: Why is our water pressure low?

A: The most common cause is debris caught in the aerator screen in your faucet. Remove the screen and clean and replace. There are two other common causes for most low water pressure situations. The first problem is partially closed valve on the property being served. The second low pressure situation is caused from aged galvanized steel plumbing which has become restricted due to interior corrosion and mineral deposit build-up. A less frequent water pressure problem can be caused if the dwelling has pressure regulator that has worn out or failed.

Q: Why does my neighbor have more, or less, water pressure?

A: This could be caused by the pressure zone your neighbor is in. The City has fourteen different pressure zones ranging from 40lbs. up to 125lbs depending on the time of day. This problem may also be caused by differing pressure regulator settings or the type of pipe material used on the customer side.

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Meter Reading, Customer Service

 - Know Your Water Meter

Q: Why do I have a high water bill?

A: There are numerous possibilities for a high water bill. Have you found any wet spots in your house or yard? Have you noticed any faucets dripping? Does your toilet sound like it is running all the time? All of the above can contribute to significantly higher than normal water bills.

Q: Why don’t I have any water?

A: If you just moved into your house or apartment you have to sign up for service. If you already have water service, you should be aware that the water distribution system occasionally has main line breaks. When this happens, the crews rarely have the opportunity to notify the public. In an emergency shutdown such as this, distribution crews notify the police of the areas that will be affected. For a planned water main shutdown, crews give 24 hour notices to customers in the area the shutdown will affect.

Q: How often is my meter read

A: Once a month.

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Q: Why is my current water bill so much higher than my last?

A: A malfunctioning or leaking toilet is the most common problem, and it may be responsible for the sudden increase in your water bill. If you hear the sound of water running when your toilet is not in use, it can be wasting 100-500 gallons of water per day. To learn how to detect or repair toilet leaks or find other useful water conservation information, visit the Utilities Conservation web page, or call 781-7215.

Q: I want more information on curbside recycling; where do I sign up?

A: Our residential recycler is San Luis Garbage Company. There is no additional charge for residential recycling, so call 543-0875 to sign up. They also offer a greenwaste recycling program, and literature that explains how to recycle.  Commercial and multifamily accounts can recycle by calling 543-0875.

Q: How can I recycle my hazardous waste?

A: Both Cold Canyon and Chicago Grade Landfills have developed hazardous waste drop-off facilities that are open to the public on an ongoing basis. The basic limitations are fifty gallons of liquid or 125 lbs. Of other materials per visit. Most materials are accepted except for biological hazards, explosives, and nuclear wastes. Hours are Saturday, 11:00 a.m. to 3:00 p.m. businesses must make an appointment, but private citizens can just show up. Rain cancels. For more information or appointments, call the Integrated Waste Management Authority at (800) 400-0811 or 782-8530 (Mon-Fri). Available to all county residents except residents of the City of Paso Robles.

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Water Reuse

Q: How is water recycled?

A: The City of San Luis Obispo Water Reclamation Facility produces a disinfected tertiary recycled water by removing the waste from wastewater that residents discharge to the sewer. This recycled water is suitable for irrigation and many other uses. The Water Reclamation Facility uses the biological and mechanical processes described below to produce this high quality recycled water.

  • Primary treatment uses bar screens and settling basins to remove materials that settle or float.

  • Secondary treatment uses bacteria and other microorganisms to remove carbonaceous wastes and to convert ammonia to nitrates. The Water Reclamation Facility uses trickling filters and activated sludge basins to raise these microorganisms and then uses clarifiers following each of these processes to remove the microorganisms from the water. Following secondary treatment 95-98 percent of the organic material and solids have been removed.

  • Tertiary treatment cools, filters, and disinfects the water before it is provided for reuse and dechlorinates the water that is discharged to the creek.

Q: Is recycled water safe?

A: The use of recycled water is regulated by the State of California Department of Public Health, the same agency that regulates drinking water. The recycled water produced by the City of San Luis Obispo is suitable for irrigation of playgrounds and all food crops as well as many other uses. It is not approved for drinking, food preparation, or swimming. However, the incidental contact or consumption of this recycled water which might be anticipated with the approved uses is not harmful.

Q: Where will recycled water be used?

A: A separate distribution system was constructed to deliver recycled water. It will be distributed to customers who have a large demand for water. Including parks, schools, athletic fields, highway landscaping, and landscaping in commercial and multifamily residential areas.

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Wastewater Collection

Q: Who do I call when I have a sewer problem?

A: Call the City Corporation Yard dispatchers at 781-7220 during normal operating hours (Monday-Friday 7am to 4:30pm). After hours calls should be directed to Police Communications at 781-7312.

Q: What part of the sewer system am I responsible for?

A: The homeowner is responsible for their sewer lateral from the house to the connection at the City main (usually located in the street).

Q: I have heard of the Sewer Lateral Rehabilitation Program. What is it and how can I participate?

A: Participation in the sewer lateral program was voluntary and was developed by the City to assist homeowners if they had a defective lateral. Unfortunately, we no longer have this program.

Why do we pay sewer fees?

A: Sewer fees pay for the complete operation and maintenance of the collection, treatment and pretreatment programs. The sewer fund is self supporting and does not receive money from outside sources such as the General Fund.

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Q: I don’t put hazardous waste down the sewer so why should I be on permit?

A: Although almost everyone in the City is in compliance the City still needs to perform inspections to verify compliance. Without inspection the City has no way of knowing if a facility is in compliance. The purpose of the program is to ensure hazardous wastes are not discharged.

Q: Why do I have to open a grease trap or clarifier? Why can’t the inspector do this?

A: An inspector can’t do this because of liability questions and risk of injury. The City does not work on any private facility or device for this reason. The owner of the business is responsible for maintaining the trap, interceptor or clarifier and is also required to open it for inspection.

Q: Where can I get a copy of the sewer use ordinance?

A: From the City Clerk’s office @ 990 Palm Street. Phone # 781-7100.

Q: Why do I need a grease trap and how is sizing a trap determined?

A: All restaurants, commercial kitchens, food processing, etc.. are required to have a grease trap. Because of the larger then normal amount of grease that may come from a facility, (as compared to a household), a trap is required to remove the grease before it reaches the sewer. Sizing is determined using the Uniform Plumbing Code (UPC).

Q: What happens if I’m out of compliance? Will I be fined?

A: Not at first. The City is interested in compliance rather then collecting fines. If a violation is noted then a Notice of Violation (NOV) is issued. The NOV will clearly state the violation, what needs to be done to correct the problem, and a completion date when the violation must be corrected. If not enough time is given to correct the violation the facility may request more time to come into compliance. Enforcement actions like fines, civil or criminal lawsuits or water/wastewater service shut off are only enacted if the facility has shown little or no effort to correct the violation or the violation is significant and/or intentional.

Q: Can I contest my classification or being on permit?

A: Yes. A facility needs to submit a letter to request being taken off permit or a change in classification. After that, the City will evaluate your facility using inspections or inspection records and any information provided.

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Water Resource Recovery Facility

Q: What are the sources of wastewater?

A: Wastewater is comprised of water from toilets, sinks, showers, manufacturing, laundromats, etc. Rainwater and runoff from the streets are collected in separate stormwater sewers and released to local waterways.

Q: What are the costs to operate the plant per year?

A: 3.2 million dollars per year.

Q: How many people work there?

A: 8 operators, 4 maintenance technicians, 1 plant supervisor, 3 lab analysts, 1 lab director, 1 pretreatment inspector, 1 pretreatment manager.

Q: Are discharge requirements hard to meet?

A: At times meeting requirements can present a significant challenge. Since our advanced treatment systems are biological in nature, they are influenced by weather, diurnal changes, wastewater flow changes, waste-strength fluctuations, etc. Meeting our stringent discharge standards requires our facility to always operate at its optimum level.

Q: What significant change have you seen in the creek and or habitat?

A: Steelhead and Salmon are now making their way upstream of the Water Resource Recovery Facility outfall that is several miles from the ocean.

Q: What laws govern wastewater treatment, wastewater collection and pretreatment?

A: The Clean Water Act (CWA) is the principal law that governs all of these programs. The CWA’s primary objective is to restore and maintain the chemical, physical and biological integrity of the Nation’s waters.

Q: How does the CWA work?

A: The formal mechanism for implementing the CWA is the permitting system known as the National Pollutant Discharge Elimination System (NPDES) permit. NPDES permits are required for all dischargers to U.S. waters. The City’s Water Reclamation Facility is issued a permit with specific requirements that protect San Luis Obispo Creek. Maximum fines for violating the permit can range from $25,000 to $1,000,000/day.

Q: How does the CWA affect wastewater collection and pretreatment?

A: Both of these programs have requirements relating to the CWA and the City’s NPDES permit. Discharge of untreated wastewater from the collection system is considered a discharge violation and these requirements are covered in the City’s NPDES permit. The pretreatment program has a section in the CWA that specifically lists all the requirements for the program and the industries it must monitor, sample and inspect. The City’s NPDES permit also has a pretreatment section.

Q: Does the City have any other CWA programs?

A: Yes. The City also has a general industrial storm water permit and a biosolids program. The storm water program addresses the pollutants coming from non-point sources from specific City facilities. This program ensures that the facilities are reducing the pollutants in their storm run-off by ensuring materials are stored properly, facilities are maintained and procedures are followed that reduce pollutants discharged into storm water. The program inspects, samples and monitors these facilities to ensure compliance.

Q: Lately I’ve heard several references to biosolids. What are biosolids?

A: Biosolids are the treated solids removed from the waste stream during treatment. The City’s biosolids are anaerobically digested to reduce and stabilize organic materials and virtually eliminate potential pathogens. If there are any measurable levels of harmful materials such as metals and other toxics, those levels meet all of the stringent Federal and State environmental standards.

Another common name for biosolids is nitrohumus. Nitrohumus is commercially available as Milorganite and Kelloggs compost at your local nursery. The City’s biosolids are currently recycled for agricultural application in the San Joaquin Valley.

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