HomeMy WebLinkAbout05/18/2010, SS3 - COUNCIL STUDY SESSION REGARDING RAINWATER HARVESTING Council Mus8- 8- �o
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CITY OF SAN LUIS OBISPO
FROM: John Mandeville, Community Development Director
Prepared By: Tim Girvin, Chief Building Official
SUBJECT: Council Study Session Regarding Rainwater Harvesting
RECOMMENDATION
Following the Study Session on Rainwater Harvesting 1) Direct staff to develop a Rainwater
Harvesting Ordinance. 2) Direct staff to collaborate with SLO Green Build and the San Luis
Obispo County Environmental Health Department to develop guidelines for the installation and
maintenance of rainwater harvesting systems.
DISCUSSION
After receiving several inquiries during the month of November 2009, Council indicated that
they would like to gain a better understanding of the City's regulations and other codes and
guidelines that may promote rainwater harvesting. Council's goal is to enable citizens within the
City of San Luis Obispo to be able to safely install and use rainwater harvesting systems.
Previous City Manager, Ken Hampian indicated that staff would conduct a study session to
discuss these issues in more detail during the Spring of 2010. Since November, staff has
reviewed various regulations and guidelines to gain a better understanding of potential-effects of
altering the codes to allow rainwater harvesting within the City of San Luis Obispo. These
included reference material provided by Mike Hicks, owner of Southern Exposure Construction,
Federal EPA guidelines and American Rainwater Catchment Systems Association (ARCSA)
Installation Standards. Additionally, staff has had preliminary discussions with County
Environmental Health Department staff and members of SLO Green Build to discuss the issue.
There are several sections below that help answer possible questions about codes and rainwater
harvesting practices which should provide adequate insight for Council to provide direction for
follow-up actions.
Water Conservation
Section 10.2.2 of the General Plan indicates that the City of San Luis Obispo will be guided by
the Ahwahnee Water Principles in planning for water operations, programs and services.
Paragraph G states the following:
"Community design should maximize the use of recycled water for appropriate
applications including outdoor irrigation, toilet flushing and commercial and industrial
processes. Purple pipe should be installed in all new construction and remodeled
buildings in anticipation of the future availability of recycled water."
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Although rainwater harvesting does not result in obtaining "Recycled" water per se, it does
utilize an alternate source of water to achieve similar results, to reduce the impacts to the potable
water supply. For this reason the General Plan is supportive of use of alternate water sources.
Health & Safety/ Potable vs. Non-potable
The City of San Luis Obispo acts as the water purveyor within our community. As such, the City
is responsible for guaranteeing that the water delivered to customers meets State and Federal
standards. To this end, the City must protect its water distribution system from threats of cross-
contamination that may occur when alternate sources of water are available at a site. There are
codes and standards available to direct the City regarding maintaining safe drinking water or
"potable water" from becoming contaminated by alternate sources of water that are used for non-
potable purposes. The EPA has published a Municipal Handbook, Rainwater Harvestine Policies
Managing Wet Weather with Green Infrastucture.. This handbook provides good direction
related to establishing a Municipal Rainwater Harvesting Program. Typical non-potable uses are
described within the publication which include irrigation, vehicle and equipment washing and
toilet flushing. Most of these activities occur outside the building and pose less of a threat of
cross contamination. However, providing an alternate source of water for activities such as toilet
flushing, which occurs inside the structure, comes with higher risk of cross-contamination. The
guidelines and standards that were researched require systems that, propose indoor use be
designed by a licensed professional. On this matter, City staff will need to collaborate with the
local health officials to determine the best process to follow for the use of rainwater harvesting
systems within the City of San Luis Obispo.
Stormwater Regulations and the Water Quality Act
Much work has occurred related to the development and approval of the City of San Luis
Obispo's Stormwater Management Plan (SMP). The SMP, which was approved by the Regional
Water Quality Control Board less than a year ago, is a five year plan. This plan includes
numerous Best Management Practices, or BMP's that are to be instituted within specific
timelines. Year two requirements include the need to introduce Low Impact Development
standards and aggressive hydromodification requirements for new development.
Hydromodification is the process of calculating the volume of water that may be produced by
covering a site with non-porous materials like structures or parking lots then providing
enhancements within the development to limit stormwater from exiting the site.
Many of these strategies include the use of rain gardens, bioswales or other rainwater harvesting
techniques to limit the impacts to creek environments. More changes are anticipated as the City
strives to fulfill its obligations to the State, be in conformance with the Federal Water Quality
Act and ultimately enhance the safety and effectiveness of its water basin. The City of San Luis
Obispo, like many other communities, will be looking for strategic ways to solve stormwater
management issues. The use of rainwater harvesting combined with rain gardens will help the
City solve many of those issues. By laying a good foundation now that we can build upon as
stricter water quality requirements come our way is just good planning.
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Green Building Standards & Codes
The City of San Luis Obispo is preparing to go green. The State of California has developed and
approved a new Green Building Standards Code which is slated for local adoption in January
2011. These "Green" codes are now Part I I of the California Code of Regulations, Title 24,
otherwise known as the California Building Standards Code. The purpose of this code is to
improve public health, safety and general welfare by enhancing the design and construction of
buildings through the use of building concepts having a positive environmental impact and
encouraging sustainable construction practices. Much other development of standards and
regulations is occurring related to building green. The International Association of Plumbing and
Mechanical Officials (IAPMO) have published the Green Plumbing & Mechanical Code
Supplement. IAPMO is a consortium of professionals that develop and publish the Uniform
Plumbing Code and the Uniform Mechanical Code, both of which are adopted by the State of
California and are used as base documents for the California construction codes. IAPMO and
ARCSA have collaborated to create the IAPMO Green Code; a publication that provides an
entire chapter related to safe design of alternate water sources. Although the 2008 California
Green Code Section 604.5 Rainwater or Stormwater Collection Systems, promotes the voluntary
use of rainwater harvesting systems, it lacks the technical information required to design
rainwater harvesting systems. Through the City's code adoption process it would be possible to
enhance the California Green Code to incorporate reference to prescriptive guidelines such as the
IAPMO Green Code supplement or other reference documents which would allow for safe
installation and maintenance of rainwater harvesting systems within the City of San Luis Obispo.
Types of Systems
Rainwater harvesting can be categorized into three types of systems that become increasingly
more complex.
First, the use of rain-barrels; these are becoming popular with the general public and are the
simplest of the systems. This is the large barrel or 55 gallon drum that is strategically placed to
gather the roof drainage. Several can be combined to allow for greater storage capacity and they
are typically equipped with a faucet near the bottom of the barrel so watering cans can be filled or
a hose could be attached to irrigate landscaping with ease. Other designs include use of drip
irrigation directly fed from this harvested water supply that can be isolated with valves to help
coordinate the proper application of irrigation water. These types of systems are simple to
install, have limited maintenance requirements and can be installed without a permit.
Second, the use of a cistern; these are larger capacity storage systems, typically buried
underground and equipped with a pump. This system would be utilized for outdoor irrigation
and other incidental outdoor uses such as car washing, washing walkways or other site cleanup
activities. Depending on the owner preference these systems could store hundreds or even
thousands of gallons which could provide for long term landscape watering. 'Systems of this size
may have more maintenance activities associated with them and water quality could be of a
concern due to prolonged storage time. These systems could be designed by a contractor with
proficient knowledge in rainwater harvesting systems, requires annual maintenance activities that
are more vigorous and would require issuance of a permit.
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Lastly, the use of a cistern associated with limited indoor use; the design principles remain the
same, however the use of alternate water sources indoors does pose a health risk and extra
protection measures are required to protect consumers from cross contamination issues. Cross
contamination regulations are primarily enforced by the SLO County Environmental Health
Department and strict adherence is mandated. Non-nal cross connection prevention remedies are
the use of an air-gap combined with installation of a back-flow protection device that is subject
to an annual testing and maintenance schedule that is administered by the county. Due to the
health issues associated with these systems and based on recommendations in EPA guidelines we
would require these systems be designed by a licensed design professional.such as an Architect
or a Mechanical Engineer. These systems obviously would also need health department approval
and the issuance of a City permit.
Pitfalls & Benefits
There are but a few pitfalls related to the use of rainwater harvesting systems. Primarily, there
are still standards to meet; it will not be as simple as setting a barrel under a drain spout then
utilizing the water. All guidelines indicate that appropriate planning and proper installation and
maintenance of these systems is key to realize the greatest benefit without suffering negative
impacts of the use of this alternate source of water, especially when the proposed use is for
indoor activities. Secondarily, it takes commitment from the individuals involved in the safe
operation of rainwater harvesting systems. Without the commitment from the community
members to operate and maintain these systems once installed, the City may have code
enforcement issues to deal with. Lack of maintenance or poor management of harvested
rainwater could lead to deterioration of neighborhood conditions due to threat of insect
infestations, microbial health hazards, improper drainage or contamination of the City's
waterways.
The main benefit for the City of San Luis Obispo is that approval of rainwater harvesting
regulations will help provide community members with safe guidelines for the use of harvested
water that would otherwise come from the City's potable water supplies. Creative use of the
City's resources will be essential for continued quality of life within the community and reducing
impacts to the City's water supplies will help the City of San Luis Obispo move the in a"green"
direction.
NEXT STEPS
The Chief Building Official will collaborate with the necessary groups in order to determine the
appropriate protocols and/or standards to be used for our Rainwater Harvesting Program.
Furthermore, the Chief Building Official will be responsible to incorporate necessary changes
into the City's local construction codes which will be presented to Council for approval during
the fall of 2010 for a January 1, 2011 implementation date, which coincides with the statewide
code adoption timeline.
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Stakeholder meetings will include members of SLO Green Build, and USGBC C4, as well as
other interested parties such as the Siena Club, Eco SLO, the Surfrider Foundation and local
construction and design professionals.
CONCURRENCES
Jon Williams, Backflow Prevention Coordinator for SLO County Environmental Health
Department has been consulted and agrees to help coordinate the City's efforts. Andy Pease of
the SLO Green Build organization has reviewed and provided feedback and the Utilities
Department concurs with this report.
FISCAL IMPACT
Because the development and approval of these regulations coincides with the triennial adoption
of the City's construction codes which includes adoption of the Green Building Standard Codes,
there will be minimal fiscal impact associated with the adoption of the rainwater harvesting
regulations.
ALTERNATIVES
Council may allow the Chief Building Official to approve rainwater harvesting systems on a
case-by-case basis as an "Alternate Materials or Method" of code compliance which is allowed
within the current regulations.
� L �
From: Donna Godfrey[SMTP:DHGODFREY@CHARTER.NET]
Sent: Thursday, May 20, 2010 8:21:59 AM
To: Council, SloCity
Subject: Downtown Association
Auto forwarded by a Rule
Please don't let them get away with shoving the Farmers Association aside.
The Downtown people seem to think they should call the shots on everything-that is
the Council's job, not theirs. Cancel or amend their contract if necessary,they are not
indispensible. Thank you. DG, San Luis Obispo
Com '