Division II. Sewers

Chapter 13.20


13.20.010    Purpose.

13.20.020    Scope.

13.20.030    Definitions.

13.20.040    Discharge – Permit – Required.

13.20.050    Discharge – Permit – Procedure.

13.20.060    Service suspension – Grounds.

13.20.070    Service suspension – Effect.

13.20.080    Personnel authorized to inspect premises.

13.20.090    Sampling and testing.

13.20.094    Discharge of certain waters and wastes to sanitary sewers.

13.20.096    Prohibited wastewater discharges.

13.20.100    Prohibitions from sewer.

13.20.110    More stringent limits permitted.

13.20.120    Precautions against entry of unauthorized materials to sewer.

13.20.130    Procedure for suspension or revocation of permit – Notice and hearing.

13.20.140    Procedure for requested restoration of permit and service – Imposition of conditions.

13.20.150    Rules and regulations.

13.20.160    Appeals.

13.20.170    Exception by special agreement.

13.20.010 Purpose.

The need for this chapter is to:

A. Comply with the requests from the San Francisco Bay Regional Water Quality Control Board regarding:

1. Elimination of the toxicity contained in the treatment plant discharge;

2. Implement immediate corrective measures to reduce the pollution load being discharged by the treatment system to New York Slough.

B. The city desires to protect the health, welfare and safety of its citizenry by determining the proper regulations for the use of its waste collection, treatment and disposal system.

C. The continued use of the city’s sewerage system will require a permit system. [Ord. 620 C.S. Art. I § 1.01, 1971.]

13.20.020 Scope.

The scope of this chapter shall include:

A. The preparation of a waste discharge permit application that will require the discharger to provide detailed information on the plan processes and waste discharged to the sewer system;

B. The dischargers must cooperate with the city in this program and provide accurate and realistic information;

C. An accurate description of the waste by the dischargers will be required to be included with the permit applications;

D. Waste dischargers will be required to pay for laboratory analysis of the industrial waste discharge for the constituents specified by the city;

E. The data compiled under this program should represent all information necessary to develop a comprehensive industrial waste ordinance. The requirements of this chapter are applicable to any and all new or prospective users of the sewer system and to any and all existing users of the sewer system. [Ord. 620 C.S. Art. I § 1.02, 1971.]

13.20.030 Definitions.

For the purpose of this chapter, the following words and phrases shall mean and include definitions contained in this section:

“Backwater valve” means any check valve or other device to prevent the flow of sewage from the public sewer into the building.

“Building drain” means that part of the lowest horizontal piping of a drainage system which receives the discharge from soil waste and other drainage pipes inside the walls of the building and conveys it to the building sewer beginning two feet outside the outer face of the building wall.

“Building sewer” means that part of any sewer piping beginning at the junction thereof with any house plumbing system (“building drain”) at not closer than two feet outside the foundation wall of the building serviced and terminating in any main sewer or trunk sewer.

“Clerk” means the city clerk.

“Connector” is any person that connects any building sewer or house lateral.

“Domestic sewage” is defined as a combination of liquid or water carrying human or kitchen waste conducted away from the residence, business, commercial or institutional buildings.

“Engineer” means the city engineer or any person designated by the council to perform the services or make the determinations permitted under this chapter to be made by the engineer.

“Garbage” means solid wastes from the preparation, cooking and dispensing of food, and from the handling, storage and sale of produce.

“Grease removal equipment” means interceptors and traps installed in commercial and industrial facilities for the purpose of reducing the quantity of fats, oils, and grease discharged to the sanitary sewer.

“House lateral” is that portion of the building sewer within a public street or public easement.

“House sewer” is that portion of the building sewer within private property.

“Industrial sewage” is defined as a combination of liquid or water-carried waste resulting from a manufacturing process employed in industrial establishments, including the washing, cleaning or drain water from such process. This includes wastes from commercial establishments that are not classified as domestic sewage.

“Installer” is any person that installs main or trunk sewers within the city limits for connection to the city sewer system.

“Main sewer” means any sewer constructed in a street or public easement to accommodate one or more building sewers or house laterals.

“Occupant” means any person actually occupying any premises, whether as owner or tenant or under contract or otherwise.

“Owner” means the person owing fee title to any premises as shown by the official records of the county recorder.

“Person” is any individual, firm, partnership, company, corporation, association or government agency.

“Premises” means any lot, or any piece or parcel of land comprising two or more lots of record in one ownership, or any building or other structure or any part of any building or structure used or useful for human habitation or gathering or for carrying on a business or occupation or any commercial or industrial activity.

“Public corporation” means the county or any political subdivision, city, county, district, the state or the United States of America, or any department or agency thereof. The singular in each case includes the plural.

“Septic tank” means a watertight receptacle which receives the discharge of a drainage system or part thereof, designed and constructed so as to retain the solids, digest the organic matter through a period of detention and allow the liquids to discharge into the soil outside of the tank through a system of open joint piping or a seepage pit.

“Sewage treatment plant” means any arrangement of devices and structures used for the treatment of domestic and industrial sewage.

“Sewer service” means the services and facilities for collection, treatment and disposal of sewage furnished or available to premises by the sewerage system.

“Sewerage system” means the city sewage treatment and disposal plant together with all public sewers heretofore or hereafter constructed and/or owned by the city, all comprising the sewerage system of the city.

“Street” is any public highway, road, street, avenue, alley, way, easement or right-of-way.

“Trunk sewer” is the sewer in the street constructed to accommodate more than one main sewer.

“User” is any owner or renter of any premises connected to a trunk sewer or main sewer for the purpose of disposing of any sewage from the premises. [Ord. 10-1324 § 3, 2010; Ord. 620 C.S. Art. II, 1971.]

13.20.040 Discharge – Permit – Required.

Permits to discharge into the sewerage system of the city anything but domestic sewage will only be granted in accordance with and in consideration of the conditions of this chapter and shall be subject to reasonable rules, regulations and requirements.

No person shall discharge or cause to be discharged any substances, materials, waters or wastes if such waste can harm either the sewers, sewage treatment process or equipment, have an adverse effect on the receiving stream, cause the city to violate the discharge requirements established by the State Regional Water Quality Control Board, or can otherwise endanger health, safety, public property or constitute a nuisance. [Ord. 687 § A, 1976; Ord. 620 C.S. Art. III § 3.01, 1971.]

13.20.050 Discharge – Permit – Procedure.

Each person, presently discharging anything except domestic sewage into the sewer system at the time that the ordinance codified in this chapter takes effect, shall submit an application to the office of the engineer.

No person discharging anything except domestic sewage shall make a connection to the sewer system without first applying to the engineer for an application.

All applicants for a permit to discharge anything except domestic sewage to the sewer system shall fill out and file with the engineer an industrial waste questionnaire as a prerequisite for the consideration of such a permit. The following is a partial listing of information to be furnished by the applicant for a permit:

A. Details of production, number of employees, water consumption and usage, waste disposal facilities and other pertinent data to enable the engineer to properly determine the nature of the waste being discharged;

B. Plan of the properties showing accurately all sewers, drains and sewer connections;

C. Laboratory determination of the characteristics of the sewage, industrial waste or other waste discharged to the sewer system, when required by the engineer. To assist with the development of the industrial waste ordinance and the permit program, such laboratory determination shall be performed at the expense of the applicant;

D. The installation and maintenance by the discharger, at his own expense, of a suitable control manhole in the portion of the building sewer located on private property to facilitate observation, sampling and measurement of the waste. Such manhole, when required, shall be accessible and safely located and shall be constructed in accordance with plans and approved by the engineer;

E. The installation and maintenance by the discharger at his own expense of grease, oil and sand interceptors or traps that are necessary for the proper handling of liquid wastes, containing grease and excessive amounts of any inflammable waste, and other harmful ingredients. All interceptors or traps shall be of an approved type and capacity and shall be so located as to be readily and easily accessible for cleaning and inspection;

F. A plan view and schematic flow diagram of existing and/or proposed industrial waste pretreatment facilities, showing sizes and design capacities of various treatment units and including a verbal description of how these facilities operate. [Ord. 620 C.S. Art. III § 3.02, 1971.]

13.20.060 Service suspension – Grounds.

The engineer may direct the discontinuation of sewer service to a user, if he determines that one or more of the following conditions apply:

A. The applicant has not fully answered the application for the permit or furnished information required by this chapter in connection therewith;

B. The application for a permit contains false statements or misrepresentations;

C. The applicant’s existing or proposed discharge does not conform to the provisions of this chapter;

D. For violation of any provisions of this chapter or of any directive or regulation issued pursuant thereto;

E. To discharge to the sewerage system any waste that may cause the city to violate the discharge requirements established by the State Regional Water Quality Control Board. [Ord. 620 C.S. Art. III § 3.03, 1971.]

13.20.070 Service suspension – Effect.

Upon the suspension or revocation of sewer service, the city shall terminate services and shall disconnect the sanitary and industrial waste connection.

The city may continue sewer service and may continue sanitary and waste disposal connection facilities upon removal of the grounds for the suspension of sewer service by the discharger and upon such other terms and conditions as shall be authorized by this chapter and imposed by the engineer. [Ord. 620 C.S. Art. III § 3.04, 1971.]

13.20.080 Personnel authorized to inspect premises.

The city manager and other duly authorized employees and agents of the city, bearing credentials and identification, shall, in all cases affected by this chapter, be permitted to enter upon all properties for the purpose of:

A. Determining the size, depth, location and condition of any sewer or storm drain connection;

B. Determining the location of discharge connection, roof and surface drains, and plumbing fixtures;

C. Inspecting, observing, measuring, sampling and testing the quantity, consistency and characteristics of water and wastes being discharged into any public sewer or natural outlet;

D. Reviewing documentation related to the maintenance of grease removal equipment;

E. Inspecting, observing, measuring, sampling, and testing the performance of grease removal equipment;

F. Observing food preparation, cooking, and dishwashing operations in order to determine whether best management practices reducing grease discharge are being followed. [Ord. 10-1324 § 3, 2010; Ord. 687 § B, 1976.]

13.20.090 Sampling and testing.

All measurements, tests, and analyses of characteristics of waters and wastes to which reference is made in this chapter shall be determined in accordance with the latest edition of “Standard Methods for the Examination of Water and Wastewater” published by the American Public Health Association, and shall be performed upon suitable samples taken at the control manholes. In the event that no special manhole has been provided, the control manhole shall be considered to be the nearest downstream manhole in the public sewer to the point at which the building sewer is connected. Sampling shall be carried out by customarily accepted methods to reflect the effect of constituents upon the sewage works and to determine the existence of hazards to life, limb and property. [Ord. 687 § B, 1976.]

13.20.094 Discharge of certain waters and wastes to sanitary sewers.

No person shall discharge or cause to be discharged any substances, materials, waters, or wastes if such wastes can harm either the sewers or the sewage treatment process or equipment, have an adverse effect on the receiving stream, cause the city to violate the discharge requirements established by the regional water quality control board, or can otherwise endanger health, safety, or public property or constitute a nuisance. [Ord. 10-1324 § 3, 2010.]

13.20.096 Prohibited wastewater discharges.

No person shall discharge or cause to be discharged any rainwater, stormwater, groundwater, street drainage, subsurface drainage, or yard drainage into any pipe which is directly or indirectly connected to the sewerage system. [Ord. 10-1324 § 3, 2010.]

13.20.100 Prohibitions from sewer.

Except as provided in PMC 13.20.100 through 13.20.170, no person shall discharge or cause to be discharged any of the following described waters or wastes to any public sewer:

A. Any gasoline, benzene, naphtha, fuel oil, or other flammable or explosive liquid, solid or gas;

B. Any ashes, cinders, sand, mud, straw, shavings, metal, glass, rags, feathers, tar, plastics, wood, paunch manure, or any other solid or viscous substances capable of causing obstruction to the flow in sewers or other interference with the proper operation of the sewage treatment plant;

C. Any garbage that has not been properly shredded, where proper shredding is defined as having not more than five percent by weight (determined on a dry basis) of all material discharged less than one-fourth inch in its largest dimension, and no particle greater than one-half inch in its largest dimension;

D. Any garbage, or any fruit, vegetable, animal or other solid material from any food-processing plant or other industrial plant irrespective of whether or not the same has been first passed through a mechanical grinder, and no person shall install, operate, or use or maintain upon the premises of any food-processing plant, or any other industrial plant, any mechanical garbage or waste grinder that is connected directly or indirectly to the sanitary sewer system of the city, or any part thereof;

E. Any liquid or vapor having a temperature higher than 150 degrees Fahrenheit;

F. Any waters or wastes having a pH lower than 6.5 or higher than 10.0 or having any other corrosive property capable of causing damage or hazard to structures, equipment and personnel of the sewage works;

G. Any waters or wastes containing:

1. Floatable grease, oil or fat of animal or vegetable origin in excess of 25 milligrams per liter,

2. Floatable grease, oil or fat of mineral origin in excess of 10 milligrams per liter,

3. Dispersed grease, oil or fat in excess of 200 milligrams per liter;

H. Any noxious or malodorous substances which by themselves or by interaction with other wastes may create a public nuisance or hazard or make human entry into the sewers extraordinarily hazardous;

I. Any water or waste having a five-day biochemical oxygen demand greater than 300 milligrams per liter;

J. Any water or waste having greater than 350 milligrams per liter of suspended solids;

K. Any water or waste which exerts or causes excessive discoloration;

L. Any unusual volume of flow or concentration of waste constituting a “slug” where “slug” is defined as any discharge of water, sewage, or industrial waste which in concentration of any given constituent or in quantity of flow exceeds for any period of duration longer than 15 minutes more than five times the average 24-hour concentration or flows during normal operation;

M. Any water or wastes containing dissolved sulfides in excess of 1.0 milligram per liter;

N. Any waters or wastes containing a toxic or poisonous substance in sufficient quantity to injure or interfere with any sewage treatment process, constitute a hazard to humans or animals, or create any hazard in the receiving waters of the sewage treatment plant. The following is a partial list of toxic substances, and their maximum concentration allowable for admission into the public sewer system:

Toxic Substances

Maximum Allowable Concentration


100 mg/liter


5.0 mg/liter


5.0 mg/liter

Arsenic and arsenicals

1.0 mg/liter


5.0 mg/liter


5.0 mg/liter


10.0 mg/liter

Bromine, iodine, chlorine

50.0 mg/liter


0.1 mg/liter

Chromium and chromium salts

0.5 mg/liter

Copper and copper salts

0.5 mg/liter

Cresols and Creosotes

2.0 mg/liter

Cyanides and nitriles

0.2 mg/liter


1.5 mg/liter


5.0 mg/liter


5.0 mg/liter


0.5 mg/liter


0.5 mg/liter

Mercury and mercurials (as mercury)

0.01 mg/liter

Methyl ethyl ketone and related substances

5.0 mg/liter


5.0 mg/liter

Phenols and their derivatives

0.5 mg/liter


2.0 mg/liter

Silver and silver compounds (as silver)

0.05 mg/liter


5.0 mg/liter


5.0 mg/liter

Zinc compounds (as zinc)

1.0 mg/liter

None of the following substances will be allowed unless specifically approved in writing by the city engineer: algacides, antibiotics, bacteriacides, fungicides, insecticides, sulfonamides, dyes; strong oxidizing agents such as chromates, dichromates, permanganates, peroxides, etc.; strong reducing agents such as nitrates, sulfides, sulfites, thiosulfates, etc.

The maximum allowable concentration of toxic or potentially toxic materials not listed above will be determined by the city engineer on an individual basis;

In no event shall any industrial waste discharged to the public sewers have a 96-hour median tolerance limit (TLm), as determined by the Routine Fish Bioassay Method, of less than 25 percent;

O. Any water or wastes containing substances which are not amenable to treatment or reduction by the sewage treatment processes employed, or are amenable to treatment only to such degree that the sewage treatment plant effluent cannot meet the discharge requirements established by the State Water Resources Board or the Regional Water Quality Control Board;

P. Any stormwater, surface water, groundwater, roof runoff, subsurface drainage, uncontaminated cooling water, or unpolluted industrial process waters;

“Unpolluted water” shall mean any water within the following limits of quality:


7.0 minimum, 8.5 maximum

Dissolved solids

1,000 mg/liter, maximum

Biochemical oxygen demand

5 mg/liter, maximum

Suspended solids

5 mg/liter, maximum

Settleable solids

0.1 mg/liter, per hour, maximum

Grease or oil


Color or odor




Q. River water which has not been contaminated by industrial use. [Ord. 687 § B, 1976.]

13.20.110 More stringent limits permitted.

When the volume of waste discharge from any single industrial establishment is greater than 10 percent of the average daily sewage flow to the treatment plant, the city engineer may impose separate or special concentration limits more stringent than those previously listed. [Ord. 687 § B, 1976.]

13.20.120 Precautions against entry of unauthorized materials to sewer.

Any physical connection to a public sewer, or to a private sewer connected to a public sewer, from vessels, tanks or containers receiving any of the materials and substances mentioned in this chapter from which quantities of such prohibited materials or substances could accidentally be discharged directly or indirectly into the public sewers, is prohibited. Precaution should be taken to prevent the accidental spillage of any of the materials mentioned in this chapter to floor drains, basins, downspouts, gutters, etc., from any manufacturing process or storage vessel. [Ord. 687 § B, 1976.]

13.20.130 Procedure for suspension or revocation of permit – Notice and hearing.

Prior to the suspension or revocation of a permit and the termination of service and disconnection of sanitary and waste disposal facilities, the city council shall notify, in writing, the owner and tenant, if any, of the property affected and for which the permit was issued. The notice shall advise that the city will consider the suspension or revocation of the permit, termination of service or disconnection. The notice shall state the date of proposed suspension or revocation, termination of service and proposed disconnection of service and the reason therefor and the time and date and place that the city council shall hold a hearing upon the proposed suspension, revocation, termination and disconnection. The hearing shall not be less than 10 days subsequent to the giving of notice as required in this section. The notice shall be mailed to the owner at the address shown on the records of the assessor of Contra Costa County or as known to the city engineer, and a copy shall be delivered to the tenant or posted conspicuously on the property affected. The city may, but shall not be required to, give such further or additional notice as in the discretion of the city engineer is convenient or desirable. Upon the conclusion of the hearing the city council shall adopt a resolution determining whether grounds exist for suspension or revocation, for termination and for disconnection of service. If such grounds are found to exist, the permit shall forthwith be suspended or revoked (as said resolution shall so determine) and service shall forthwith be terminated and sanitary and waste disposal facilities forthwith disconnected. A copy of the resolution shall be mailed to the owner at the address shown on the records of the assessor of the county or as known to the city engineer and a copy shall be delivered to the tenant or posted conspicuously on the property; provided, however, that the service of the copy of the resolution shall not be a condition precedent or subsequent to suspension or revocation, termination or disconnection. [Ord. 687 § B, 1976.]

13.20.140 Procedure for requested restoration of permit and service – Imposition of conditions.

Any person whose permit has been suspended or revoked under the provisions of this chapter, or for whom service has been terminated and disconnection effected under the provisions of this chapter, may petition the city council for reinstatement of the permit and reinstatement of service. The petition shall be verified under the oath or declaration under penalty of perjury of the person petitioning. The petition shall contain a detailed statement of the corrective action taken by the petitioner or others to remove the grounds for suspension or revocation, termination and disconnection, and of the corrective measures or devices to prevent a repetition of the offense and of proposed security against further violation. The petition shall contain the name and address of the petitioner for purposes of receiving notice. The petition shall be filed with the city engineer.

The petition shall be heard within 35 days of the date of filing by the city engineer. Notice of time, date and place of hearing shall be given to the petitioner at least 10 days before the hearing, in writing, mailed to the petitioner at the address shown on the petition; provided, however, that the petitioner may waive the notice in writing.

At the hearing the city council shall consider evidence presented by the petitioner in support of his petition and evidence in opposition.

The city council in its discretion may restore the permit, service and connection if it finds by resolution that the grounds for suspension, revocation, termination and disconnection have been corrected and that there is adequate assurance from the petitioner of corrective measures or devices to prevent a repetition of the offense for which the permit was suspended, revoked and service terminated and disconnected.

The city council may, as a condition to the restoration of the permit, service and connection:

A. Require the petitioner to provide reasonable safeguards and security to avoid a repetition of the offense for which the permit was suspended, revoked and service terminated and disconnected;

B. Impose reasonable charges in accordance with the schedule adopted by the city to compensate the city for expenses incurred by the city in connection with the suspension, revocation, termination and disconnection and in connection with the reinstatement of the permit and the restoration of service and reconnection;

C. Impose reasonable charges in accordance with the schedule adopted by the city to compensate the city for any damage to its facilities or any overload to its facilities which the petitioner should equitably be required to pay or which the petitioner would have been required to pay under the provisions of this chapter;

D. Such other reasonable conditions or regulations as shall be necessary to protect the public health, safety, property and to prevent a nuisance;

E. Such reasonable conditions or regulations as shall be necessary to comply with the requirements of the State Regional Water Quality Control Board or State Water Resources Control Board or of this city. [Ord. 687 § B, 1976.]

13.20.150 Rules and regulations.

The city is empowered to adopt reasonable rules and regulations or to impose reasonable conditions, in addition to those specifically authorized in this chapter, upon any permit issued for the purpose of implementing this chapter. A copy of the rules and regulations shall be maintained in the office of the city engineer and shall be available for inspection upon request of any member of the public. Copies of the rules and regulations shall be reproduced for sale to members of the public at a reasonable charge. Without limitation to the generality of any other provision of this chapter, a violation of the rules and regulations shall be grounds for suspension or revocation of a permit. [Ord. 687 § B, 1976.]

13.20.160 Appeals.

Except as otherwise provided by this chapter and where a hearing on the matter is not otherwise required to be had by the city council, any person aggrieved by decision of any officer or department of the city or of its engineer may appeal to the city council in accordance with procedures established by the city. [Ord. 687 § B, 1976.]

13.20.170 Exception by special agreement.

No statement contained in this chapter shall be construed as preventing any special agreement or arrangement between the city and any industrial concern whereby an industrial waste of unusual strength or character may be accepted by the city for treatment, subject to payment therefor by the industrial concern. [Ord. 687 § B, 1976.]