Virginia Law

A. The rainwater harvesting system shall be designed, installed, operated, and maintained to prevent contamination of water supplies and distribution piping.

B. Rainwater harvesting system components shall be protected from external contamination and entry by insects and vermin.

C. The rainwater harvesting system shall be sited and designed to produce and store water under local site conditions that include:

1. Excessive heat;

2. Freezing;

3. Flooding; and

4. Sunlight exposure.

D. The owner shall control access to rainwater harvesting system components to minimize unauthorized access.

E. Gutters, downspouts, and conveyance systems leading to the water storage unit shall be fitted with a screen or debris excluder to prevent the accumulation of leaves, needles, or other debris into the water storage tank or cistern.

F. Vegetation above roofs and gutters shall be removed to reduce organic matter falling on and decomposing in rainwater collection surfaces and conveyances, and to reduce or remove locations for animals to introduce contaminants.

G. Rainwater shall pass through a prefiltration system prior to entering the water storage unit or cistern. Appropriate prefiltration devices include a gutter screen, inline filters, and vortex filters to reduce organic matter, debris, and particulates from entering and accumulating in the bottom of the unit or cistern. Prefiltration devices without a self-cleaning design shall incorporate a corrosion-resistant debris screen having openings no larger than 0.15 cm.

H. A first flush device shall be used to remove accumulated debris from the collection surface before rainwater is introduced to the water storage unit. First flush diverters shall:

1. Be placed after prefiltration;

2. Operate automatically and not rely on mechanically operated valves or devices;

3. Discharge diverted rainwater in a manner consistent with local stormwater runoff requirements so as not to cause damage to a property or erosion; and

4. Be readily accessible for maintenance.

I. Inlets and outlets on the water storage unit shall be installed and supported in accordance with the manufacturer's instructions. Water storage units, including units used in series, shall each be fitted as follows:

1. Rainwater inlets to a water storage unit shall be arranged to minimize turbulent flow by means of a calming device such as a return bend elbow pointed upward at least 10 cm above the bottom of the tank.

2. Outlets shall be positioned, and floating collared offtakes shall be used below the top water level in the unit to draw water from the cleanest strata of the unit.

3. Overflow outlets or flap valves shall be protected with a screen having openings no greater than 1.5 mm to prevent entrance of insects or vermin into the unit.

4. The vent shall be minimum 38.1 mm diameter and be protected with mesh having openings no greater than 1.5 mm to prevent entrance of vermin and particulates.

5. Rainwater outlets and pump suction shall be located at least 100 mm above the bottom of the unit. If a floating pump is used, it shall draw water from below the water surface.

6. Pipe penetrations through unit walls shall be watertight and shall comply with the USBC. Pipe penetrations shall not prevent access to the unit for inspection or cleaning.

J. A rainwater harvesting system shall be equipped with filtration systems conforming to the standards specified in 12VAC5-635-250 and 12VAC5-635-340 and shall:

1. Be installed in accordance with the USBC;

2. Be accessible for inspection and maintenance;

3. Provide indication when servicing or replacement is due; and

4. Incorporate shutoff valves immediately upstream and downstream to allow for isolation during maintenance.

K. A rainwater harvesting system shall be equipped with disinfection systems that:

1. Conform with the standards specified in 12VAC5-635-260 and 12VAC5-635-340; and

2. Are designed and installed in accordance with the manufacturer's instructions and the USBC.

L. A rainwater harvesting system for Tier 3 and Tier 4 end use shall be equipped with a fail-safe system for disinfection systems, with alerts and alarms as follows:

1. Alerts shall be provided for critical control points identified in the operation and maintenance manual to indicate when the rainwater harvesting system is operating outside design parameters but not causing a hazard to health or safety or damage to system components.

2. Alerts shall have a visible output and may have an audible output.

3. Alarms shall be provided for critical control points identified in the operation and maintenance manual to indicate when the rainwater harvesting system is operating outside the design parameters and potentially causing a hazard to health or safety or damage to system components.

4. Alarms shall have visible and audible outputs.

5. A remote alarm of an alert system using electronic communication shall be used to notify the operator that the system has failed or that failure is imminent.

M. Separation shall be maintained between potable and nonpotable distribution systems by means of color coded and labeled piping and cross-connection control in accordance with the USBC.

N. Controls for rainwater harvesting systems supplying water for fire sprinkler systems or standpipes shall comply with the Virginia Statewide Fire Prevention Code Act (§ 27-94 et seq. of the Code of Virginia).

O. If a rainwater harvesting system is installed in any building, facility, or residence, it shall be so indicated as follows:

1. Fixtures not specifically treated for potable water use shall be labeled for nonpotable use in accordance with the USBC.

2. Fixtures not subject to the USBC and not specifically treated for potable water use shall be prominently labeled "CAUTION: NONPOTABLE WATER – DO NOT DRINK" and "ATTENCIÓN: AGUA NO-POTABLE – NO BEBER." Labels shall be indelibly printed on a tag or sign constructed of a corrosion resistant, waterproof material permanently mounted in a visible location. The letters of the labels and markings shall be at least 0.5 inches in height and shall be of a color that contrasts with the background on which they are printed. In addition to the required words, a pictograph consistent with the following shall appear in the tag or sign: