Nevada County Municipal Code Ch. 7 Treatment of Surface Water for Domestic Purposes

A. General. Treated surface water supplies used for domestic purposes must meet the provisions of: (1) The laws, standards and regulations of the California Safe Drinking Water Act; (2) California Domestic Water Quality Monitoring Regulations relating to certification of water treatment facility operation as excerpted from the California Health and Safety Code, California Code of Regulations, and the California Water Code. Surface water used for domestic purposes must be under administrative authority of a private or public entity formed for the purpose of collecting, treating, storing and distributing water for human consumption. All such entities treating surface water for drinking or domestic use shall be required to possess a valid Certificate of Operation issued by the enforcement agency and pay an annual inspection fee set by the Board of Supervisors or possess a Domestic Water Permit issued by the California Department of Health Services.

B. Conditions. A surface water source with treatment may be utilized for domestic use on a case-by-case basis if the following conditions are fulfilled:

1. For existing developed parcels where there is a legal residence and wells or springs: (a) yield less than one (1) gallon per minute, (b) are contaminated, or (c) setback requirements from the waste water disposal system prohibits the use of a well or spring;

2. A raw water source approved by the enforcing agency for treatment is available from a public or private entity either existing or to be created;

3. An affidavit stating a raw water service connection will be provided to the user is received by the enforcement agency from the Administrative Authority of said entity; and

4. Compliance with Sections 15.07.030 through 15.07.080 of this Chapter is ascertained.

The drilling and testing of a well as specified in Section 15.07.010.B.1 above may be waived by the enforcement agency on a case-by-case basis provided that valid historical data are available as provided by a well driller, geologist, civil engineer, or enforcement agency records. Said data must show that groundwater resources are minimal or nonexistent and/or groundwater is contaminated.

(Ord. 1717. (06/11/1991); Ord. 2531. (10/24/2023))

After the effective date of this Chapter, it shall be unlawful for a person or persons to utilize untreated surface water for domestic purposes for any new construction other than as allowed under the provisions stated herein. No building permit shall be issued for a dwelling proposing to use treated surface water as its source of domestic water.

(Ord. 1717. (06/11/1991); Ord. 2531. (10/24/2023))

For an existing dwelling proposing to use treated surface water as its source of domestic water, the treatment system and source shall be approved by the enforcement agency and the California State Department of Health Services. Before any water availability affidavit is issued by a private or public entity and can be approved by the enforcement agency, the water treatment system, all equipment specifications and design must meet the provisions of this Chapter.

(Ord. 1717. (06/11/1991); Ord. 2531. (10/24/2023))

A. The property owner or their designated representative must make application for a Surface Water Treatment System permit on a form provided by the enforcement agency. Said application shall include, as a minimum, the following:

1. A certificate bearing the original signature from a California registered civil engineer or a registered environmental health specialist stating that the proposed water treatment system, when properly installed and maintained, will produce water continuously meeting the California Safe Drinking Water Act, California Water Works Standards, and this Chapter. Said system shall be installed under the supervision of the designer signing the Certificate who, after the system is installed, shall certify in writing that the water treatment system has been installed in conformance with the approved design;

2. The reason and substantiation for request (e.g., hardship, less than one (1) gallon per minute yield on well, well is contaminated, etc.), along with supporting data. Said reason shall be provided on a "request for waiver" form;

3. A Facilities Plan and Project Report prepared by a California registered civil engineer or environmental health specialist. Said report shall include, as a minimum, a detailed equipment plan, materials and specifications, flow calculations, retention time, treatment method, top and side views, and other information as is necessary to justify the treatment system;

4. Analyses of raw source water samples collected and tested by a State licensed laboratory;

5. A contract agreement between the property owner and the designer or installer certifying that the contractor will maintain the system according to the approved system design.

B. All documents, information, designs, analysis reports and plans required in Subsection A above shall be submitted in triplicate.

(Ord. 1717. (06/11/1991); Ord. 2531. (10/24/2023))

A. The treatment plant, piping, and appurtenances shall be designed, located, constructed, and composed of materials sufficient to withstand the physical stresses imposed during normal operation and during all weather conditions. All portions of the treatment facilities shall be readily accessible for maintenance and operation.

B. The treatment system is to be designed and installed so that there is disinfection at all times to provide potable water for domestic use.

C. In systems with media-type filters, a proportional feed pump shall be used to add effective coagulation chemicals prior to filtration and filter in proportion to the rate of water flow. A suitable coagulant solution container shall be provided.

D. An accurate pressure gauge shall be provided on both the inlet side and on the outlet side of the filter to provide a visual assessment of pressure loss due to filter clogging and thereby facilitate proper filter backwash frequency.

E. All filters shall be constructed and installed so that the design filtration rate cannot be exceeded.

F. Filters shall be constructed so that they can be backwashed only with clear, filtered, and chlorinated water meeting drinking water standards. Backwash flow rates shall effectively clean the filter media. Piping shall be valved so that filters can be isolated for repairs while the other units are functioning. Initial filter runs, after backwash, are to be directed to waste. There shall be no bypass or leakage of untreated or partially treated water to the point of use. Other approved methods of backwash may be approved on a case-by-case basis.

(Ord. 1717. (06/11/1991); Ord. 2531. (10/24/2023))

Disinfection is to be by chlorination or other approved methods.

A. When Using Chemical Disinfection.

1. A contact tank or tanks shall be provided to allow for a minimum of thirty (30) minutes retention time to accomplish adequate disinfection during periods of peak water flow through the treatment plant. The chlorine contact facilities shall be installed in a manner which will effectively maximize retention time and reduce "short circuiting."

2. Disinfectant Solution Storage Container. A container constructed of materials resistant to corrosion by the disinfectant shall be provided for the storage of the prepared solution being supplied to the proportional disinfectant feeder. The container shall be sized to provide at least a one (1) week supply of disinfectant solution during normal demand, but not more than a two (2) week supply.

3. When using chlorine, a DPD free chlorine residual test kit with appropriate reagents shall be supplied as part of each water treatment plant installation.

B. Sampling Tap. A faucet or other suitable fixture shall be provided immediately upstream and downstream from the contact facilities to permit collection of water samples for bacteriological, turbidity, and disinfectant residual measurements.

(Ord. 1717. (06/11/1991); Ord. 2531. (10/24/2023))

A. For any installation of a surface water filtration and treatment system constructed after the effective date of this Chapter, monitoring shall be required to determine that the water system is performing satisfactorily as per the design. Monitoring shall be accomplished by any one (1) of the following:

1. A contract agreement between the property owner and the designer or installer for sample collection and analysis by a State certified laboratory, or

2. By the enforcement agency on a fee for service basis.

B. The owner or contractor shall provide the enforcement agency a report of monitoring on a quarterly basis. Said monitoring shall include, as a minimum, quarterly bacteriological sample analysis, daily turbidity analysis, and daily chlorine residual.

C. If sample results demonstrate that the treatment system is not achieving minimum water quality requirements, the designer shall submit new plans and specifications to the enforcement agency, as per Section 15.07.040, to bring the treatment system performance within minimum potability standards.

(Ord. 1717. (06/11/1991); Ord. 2531. (10/24/2023))

Use of alternative surface water treatment systems may be considered on a case-by-case basis only. Said proposed systems must provide assurance of meeting minimum potability standards and equipment reliability and otherwise conform to this Section. The State Department of Health Services shall also approve of a proposed alternative surface water treatment system. Additional testing and monitoring requirements may be imposed as a result of approval of an alternative surface water treatment system.

(Ord. 1717. (06/11/1991); Ord. 2531. (10/24/2023))

No new hookup of an existing dwelling to an untreated surface water source shall be permitted after July 12, 1991, other than by the provisions of Section 15.06.290.