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General Information Questions
• Who in the Division should correspondence be addressed
to?
All correspondence should be directed to David A. Gutierrez, Chief of
the Division of Safety of Dams, at the address shown on our home page.
• Why are annual fees needed and what do they fund?
The dam safety program currently receives funding from two sources -
application fees and annual fees. Prior to June 2003, the State’s
General Fund supported 75 percent of the dam safety program, while the
remaining 25 percent was supported by dam fees. Senate Bill 1049 (Chapter
741, Statutes of 2003) increased annual fees so that the entire program
was supported by the combination of dam application and annual fees. The
billing set forth in SB 1049 for annual fees is $420 per dam plus $116
per foot of height.
Dam fees support, in part, the monitoring of dams in certified status,
application review and construction inspection work, and engineering studies
which include hydrologic and seismic stability re-evaluations. For Fiscal
Year 05/06, the percentages for the foregoing activities were 35, 35,
and 25 percent, respectively. The remaining portion funded our general
administrative and office costs.
• How does the Division ensure the safety of dams in California?
The Division has several programs that ensure dam safety. When a new dam
is proposed, Division engineers and geologists inspect the site and the
subsurface exploration to learn, firsthand, of the geologic conditions.
Upon submittal of an application, the Division thoroughly reviews the
plans and specifications prepared by the owner to ensure that the dam
is designed to meet minimum requirements and that the design is appropriate
for the known geologic conditions. After approval of the application,
the Division inspects all aspects of the construction to ensure the work
is being done in accordance with the approved plans and specifications.
After construction, the Division inspects each dam on an annual basis
to ensure the dam is performing as intended and is not developing problems.
Roughly a third of these inspections include in-depth instrumentation
reviews. Lastly, the Division periodically reviews the stability of dams
and their major appurtenances in light of improved design approaches and
requirements, as well as new findings regarding earthquake hazards and
hydrologic estimates in California.
• What does the Division do if a dam appears unsafe?
We work closely with dam owners to identify and correct most potential
problems before they become more serious. When unsafe conditions do develop,
we work with owners and their consultants to address and remedy the condition
in a timely manner. In some cases, we may impose a reservoir restriction
limiting the water surface to a level that is judged safe. We may also
direct the dam owner to develop and/or implement an emergency action plan.
• Will an application be required for my planned alteration
or repair work?
Possibly - contact the respective Area
or Regional Engineer for clarification. As a general guideline, if
the work entails more than routine maintenance work and significantly
affects the dam or its appurtenances, an application will be required.
Some examples of work requiring an alteration application include:
• Abandoning or replacing the outlet conduit
• Modifications to the outlet system which will affect emergency
draw down requirements
• Installation of instrumentation required to monitor dam performance
• Excavation of more than a few feet into the embankment
• When should the construction fee be submitted?
For new or enlarged dams, we generally require that the construction fee
be submitted by the time the 30% design submittal is made. For repairs
and alterations, the construction fee should be submitted with the application.
• Does your agency oversee water rights or issues pertaining
to water diversions?
No, not directly. We work with the State Water Resources Control Board’s
Division of Water Rights (SWRCB) to verify that appropriate water rights
have been obtained before we issue a Certificate of Approval authorizing
storage to a specified level. Questions concerning the actual water rights
should be directed to the SWRCB. The link to their website is: http://www.waterrights.ca.gov/.
•I just purchased a property having a jurisdictional-size dam
– do I need to initiate any action?
Yes, you should start by notifying the respective Area
Engineer of this change. You will need to complete an Ownership Statement
form, which we will mail to you.
Assistance-Related Questions
• How can I arrange to review your files for this dam?
You should contact our Office Engineer, Chuck Wong, at (916) 227-4601,
to set up an appointment. We have one office statewide, located at 2200
X Street, Suite 200, Sacramento, CA 95818.
• Can you recommend an engineering consultant for me?
We don’t recommend any specific individual or firm, but we can
provide names of consultants that have worked, or are working, on nearby
projects. We also recommend that you check out the following organizations
and websites:
California Society of Professional Engineers
Telephone Number (916) 422-7788
http://www.cspe.com
Consulting engineers and Land Surveyors of California
Telephone Number (916) 441-7991
http://www.celsoc.org
California Board for Professional Engineers and Land Surveyors
Telephone Number (916) 263-2222
http://www.dca.ca.gov/pels
• Can you help me determine whether my house would be flooded or
inundated if this dam ever fails?
The Division does not review nor oversee preparation of dam inundation
maps. However, Government Code Section 8589.5 requires dam owners to submit
copies of inundation maps to the Governor’s Office of Emergency
Services. Copies of these maps are also provided to the appropriate public
safety agency of any city and/or county likely to be affected. Most local
agencies overlay these inundation maps onto their parcel map systems.
Therefore, we recommend that you contact your local emergency management
office, using the www.oes.ca.gov
web site.
• Can you tell me if the Division checks this particular
dam, and if so, how often?
We will gladly work with you to determine if the dam in question falls
under our jurisdiction. You can assist us greatly by providing us with
the dam name, affected water course, nearby town, and county in which
the dam is located. We generally inspect all jurisdictional dams at least
once per year, as part of our normal routine maintenance program. High
hazard dams are typically inspected twice a year, and special inspections
may be made in response to follow-up work. Currently, there are approximately
1,250 dams within California that fall under our jurisdiction. A listing
of these dams is on our home page.
If the dam height is 6 feet or greater and it impounds over 50 acre-feet
of water, or if the dam is 25 feet or higher and impounds 15 acre-feet
of water, the dam will be under our jurisdiction unless it is federally
owned or exempted under special provisions described in Sections 6004,
6025, or 6026 of the California Water Code. Graphical information that
summarizes the above can be found on our Jurisdictional Size Chart page.
Technical Guidance Questions
• I am planning to build a small jurisdictional-size earth
dam. What sort of geotechnical exploration is needed?
A typical field investigation should seek to identify geologic hazards
that could adversely affect the project, to characterize the engineering
properties of available earth and rock construction materials, and to
characterize the strength and permeability of the dam, spillway, and outlet
foundations. Since each site and project is unique, exploration plans
should be submitted to DSOD beforehand for review. DSOD should also be
given the opportunity to observe the site conditions firsthand during
exploration.
A typical field investigation program includes understanding the geology
of the site through geologic mapping, air photo analysis, test pits, and
borings. The engineering properties of embankment and foundation soils
are generally evaluated by sampling and laboratory testing, and field
testing such as in-place density, penetration resistance, and permeability
testing. Geophysical techniques, such as seismic refraction and shear
wave velocity testing are sometimes used. Sometimes, rock foundations
require core drilling and water pressure testing. A phased investigation
is often the most effective way to evaluate the geologic conditions and
engineering properties of a site.
• What are the Division’s requirements for outlet operation?
Our policy requires that dam owners regularly exercise (operate) their
outlets in order to demonstrate the ability to draw down the reservoir
during an emergency. Outlet controls should be exercised at least annually
and, in our presence, every three to five years. Experience has proven
that regular exercising of gates/valves helps to prevent major maintenance
problems from developing and is, therefore, part of a good maintenance
program.
We do not operate the outlet controls themselves, nor order their operation
during routine inspections. It is the responsibility of the dam owner
to develop appropriate plans when dealing with difficult outlet situations.
We accommodate reasonable delays in exercising of outlets so owners have
time to complete proper planning, coordinate with other agencies, and
perform maintenance and repairs, if necessary.
• Does the Division have specific outlet dewatering requirements
for large dams/reservoirs?
Yes, our guidelines are summarized below:
For reservoirs that impound 5,000 acre-feet of water or less, the outlet
system should be capable of draining half of the reservoir volume within
a week.
For reservoirs that impound over 5,000 acre-feet of water, the outlet
system should be capable of lowering the maximum storage depth by 10 percent
within 10 days.
• How is dam height determined when evaluating jurisdictional
status?
Jurisdictional height of a dam is the vertical distance measured from
the lowest point at the downstream toe of the dam to its maximum storage
elevation which is typically the spillway invert elevation. This same
approach is also used for calculating the dam height for determining the
annual fee.
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