EXHIBIT 3-B

DRAFT RAINWATER HARVESTING INFORMATION

MPWMD Matrix - Alternative Water Source: Rainwater Harvesting (CISTERNS)
DECISION ELEMENT	Rainwater Harvesting - Cisterns
PROPONENT/SPONSOR	MPWMD
PROJECT DESCRIPTION	The Monterey Peninsula Water Management District’s mission includes augmenting the water supply and promoting water conservation. Catchment, storage, and reuse of greywater, rainwater and stormwater may have the potential to fulfill both mandates.
OVERVIEW OF CISTERNS	Simple technique to store rooftop runoff and reuse it for landscaping and other nonpotable uses.
PILOT PROJECT	None planned currently
PROJECT YIELD	The average home has the potential of saving 40% on indoor use and up to 100% outdoors (when factoring in the use of greywater and rainwater to substitute for potable water). Source:2003 report, Waste Not, Want Not: The Potential for Urban Water Conservation in California
	Approx 0.62 gals of water can be collected per square foot of collection surface per inch of rainfall, An efficiency of 80 percent
TOTAL YIELD	40% on indoor use and up to 100% outdoors
APPLICATION AND DESIGN PRINCIPLES	Cisterns and rain barrels are applicable to most Non-Residential and Residential properties where there is a gutter and downspout system to direct roof runoff to the storage tank.
Cisterns	Cisterns are partially or fully buried tanks w/ a secure cover and a discharge pump. Cisterns can collect water from multiple downspouts or even multiple roofs, and then distribute this water wherever it needs to go through an electric pump.
Rain barrels	Rain barrels are 50-100 gallon covered plastic tanks w/ a hole in the top for downspout discharge, an overflow outlet, and a valve and hose adapter at the bottom.
BENEFITS AND EFFECTIVENESS	Can reduce water demand for irrigation, car washing, or other nonpotable uses. Property owners save money on water bill and public water systems experience lower peak demand and less stress on local water supplies.
	Cisterns can be used to store water for landscape purposes, even during outdoor watering bans.
	If installed and used properly, rain barrels and cisterns can reduce stormwater runoff volume through storage, and will also help to reduce the peak discharge rate.
LIMITATIONS	Benefits depend on the amount of storage available at the beginning of each storm.
	Cisterns offer no primary pollutant removal benefits.
	The water collected is for nonpotable uses only.
EFFICIENCY/WATER LOSS	Some rainwater is lost to first flush, evaporation from the roof surface, or splash-out from the gutters.
	Rough surfaces are less efficient at conveying water, and water captured in pore spaces is lost to evaporation.
	The inability of the system to capture all water during heavy storms. Spillage may occur if the flow-through capacity of a filter-type roof washer is exceeded
	Overflow rainwater will be lost after storage tanks are full
Periodic Precipitation	The more frequent the precipitation, the smaller the needed storage facility and the less the capital costs.
	California doesn't receive precipitation during the summer, early fall, and late springs, cisterns are far less practical than in other parts of the county
RECOMMENDATIONS FOR RAINWATER HARVESTING	New Non-Residential buildings w/ more than 20,000 sq ft of roof area should provide a preliminary feasibility study, including cost analysis, to determine whether rainwater harvesting is viable at the site.
Comply with the District’s legislated functions to promote water reuse and reclamation of storm and wastewater	Lessen the negative impacts of required cutbacks, while simultaneously protecting existing water sources and instituting water efficiencies.
MPWMD's responsibilities	The responsible agency for developing new water supplies, promoting water conservation, managing ground and surface water and promoting reuse and recycling of storm water and wastewater; and for water distribution regulation and permitting.
RAINWATER HARVESTING	Capture runoff and use the water for various non-potable purposes w/ little treatment.
Metal roofs and non-toxic, non-leaching surface finishes	Provide highest quality rain water, if the water is to be used for drinking purposes or in-building uses such as flushing toilets and urinals
Gutter design	Should employ at least 1% slope and route water to a central collection point for transfer to cistern or storage tank
Roof washer or First-flush diverter	To minimize debris from roof surface that enters the cistern.
Landscape watering	Divert water directly into landscape areas, with swales and berms to capture and direct the flow.
Regular maintenance required	To avoid long-term pooling of water and creation of potential insect vectors. Costs are considerably lower for systems which do not include cisterns to allow it to percolate into the landscape has the stormwater runoff reduction benefits as well
CISTERN CONSIDERATIONS	Determine volume and quality of the available on-site source
	Identifying possible uses
	Matching water quality to type of use
	Deciding the type of treatment, if needed
STORMWATER HARVESTING	Can be valuable a valuable source for landscape irrigation, but only if it can be captured and held. Overall concept is to keep the rain on the site where it falls to the maximum extent possible. The water capture and held can displace part or all of the potable water otherwise used for irrigation and can optimize groundwater infiltration, water quality, and slow-release augmentation of local streams.
Three ways of Stormwater harvesting	1)Storage in soil profile;2) capture in on-site features, such as berms, swales, rain gardens, or terraces, and 3) capture in a detention structure, such a pond, from which it can be pumped back to the landscape
VARIOUS SIZES AND TYPES
Larger systems	Some may require treatment to remove contaminants or constituents
A feasibility study at site needed	To determine cost implications and payback period.
COST	Varies widely, from a homeowner installed rain cistern to a commercial constructed underground cistern vault. Cisterns provide cost savings because they reduce the demand for potable water for landscaping and irrigation. The cost-benefit will depend on how much landscaping/irrigation water the property owner uses, and the unit cost of water.
Rain barrel	approx $60 for a 55-gallon barrel
commercial grade cisterns	approx $3,000 for a 800-gallon tank w/ pump & drywell
Building permits	Case-by-case basis; See Jurisdictions
BENEFITS TO CUSTOMER
MPWMD	Rebate and WUC
COST TO MPWMD
	Currently funded in Rebate Program
TIME LINE
Prepare plan of action	February or March 2009
Present plan of action to Board	January 29, 2009
Meet w/ TAC & PAC	February or March 2009
Review previous rebated cisterns for accuracy.	February or March 2009
Draft ordinance	MPWMD lead agency.
Prepare CEQA Docs.	February or March 2009
Total time to incorporate to Rules	Six to eight months from January 29, 2009
CHALLENGES TO MPWMD	How to determine conservation potential. Need financing mechanisms. Develop policies and procedures. Limited information on construction, water savings, available.
Other agencies	Adopt local, regional, and state codes and regulations.
PERMITS/REGS
Federal Agencies	N/A
State Agencies	N/A
MPWMD	No regulations. Currently offers rebate.
Regional Agencies	No specific regulations. Regulated by the individual jurisdiction within the county.
Monterey County Agencies	MCEH, MCPBI
Environmental Health Dept.	No specific regulations. Supports cisterns for outdoor irrigation. Concerns if the cistern is on a parcel served by an onsite wastewater treatment system, i.e. septic system.
Planning Department	Regulated by MCEH; Coast Permit required coastal areas, if within 100 feet of sensitive habitat; and if is on 30% slope in either inland or coastal areas
Building Department	Regulated by California Building Code 105.2: Exempt from permit if water tank does not exceed 5,000 gallons and the ratio of height to diameter or width does not exceed 2:1
Local Agencies (Jurisdictions)
Planning Department	No specific regulations. Refer to Building Dept.
Building Department	Regulated by California Building Code 105.2: Exempt from permit if water tank does not exceed 5,000 gallons and the ratio of height to diameter or width does not exceed 2:1. Handles cisterns on a case-by-case basis.
SITE CONTROL
Sites and projects	Residential and Non-Residential Sites.
PROJECT PARTICIPANTS	CAW; partnership in rebate program. MCEH & Jurisdiction for permit requirements; MRWPCA, CAWD, and other agencies
Overview	MPWMD to issue WUC & rebates.
MPWMD participation	MPWMD currently issues $25.00 per 100 gallons ($750 max).
Other entities participation	CAW; partnership in rebate program. MCEH & Jurisdiction for permit requirements
PUBLIC INVOLVEMENT
Outreach programs	Advertisement. Inserts w/ CAW's water bill. Web-site
MPWMD	Hold Public Hearings
MPWMD	Provide education, information, and continue good communication with other agencies
INFORMATION SOURCES	Limited available information

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