Paradise Spillway Interim Risk Reduction Repair Work Project

1
SPECIFICATIONS
FOR THE CONSTRUCTION OF
PARADISE DAM SPILLWAY INTERIM RISK-REDUCTION REPAIR
Prepared for:
Paradise Irrigation District
6332 Clark Road
Paradise, CA 95969-4146
Prepared by:
GHD Inc.
320 Goddard Way, Suite 200
Irvine, CA 92618
Project No. 12656399
June 2, 2026
Paradise Irrigation District
Paradise Dam Spillway - Interim Risk Reduction Repair
GHD Project No. 12656399

DETAILED SPECIFICATIONS
ITEM 1 - MAINTENANCE CLEANING OF SPILLWAY DRAINS AND WEEPHOLES
PART 1 - GENERAL
A. Description
This work shall consist of very careful cleaning of all drains and weepholes located in the spillway
structures. Cleaning includes removal of debris and sediment inside the drains and weepholes.
Cleaning shall be accomplished in a manner that does not damage or result in clogging the drain or
weephole. Cleaning can be accomplished using wire brush, vacuuming and very low pressure
compressed air or water. Applied pressure should be very low to prevent hydraulic fracturing of
drains, weepholes, or materials surrounding the drains and weepholes. A pressure of one-half pound
per square inch (0.5 psi) per foot of depth below the existing grade is allowed at the location of the
pressure nozzle. For example, if the pressure nozzle is located 10 feet below the existing grade
directly above the nozzle, the allowable pressure is 5 psi. Since it is a very low pressure and delicate
cleaning operation, adequate time should be allowed for cleaning and use of a wireless borescope
inspection camera and/or a portable pipeline inspection camera will be needed to check the existing
conditions, progress of the cleaning, and integrity of the drains and weepholes. Camera inspection
of the drains and weepholes must be conducted after completion of the cleaning, and a detailed report
with video files shall be prepared documenting the locations of the drains and weepholes, as-built
conditions, and any deficiencies or anomalies. Approximate locations of all drains and weepholes are
shown on the plans. The Contractor shall implement safety procedures at all times to meet Cal/OSHA
(Division of Occupational Safety and Health (DOSH) of California) Standards and Regulations. The
Contractor should be aware that access into the spillway chute will not be authorized during storm
events or spill events. The Contractor is responsible for preventing debris, trash, or other materials
from their activities from entering water course downstream of the spillway structure. If there is any
deposition in water course by the Contractor's activities, the Contractor is responsible for removal
and clean up in a timely manner. All debris and trash removed from drains and weepholes shall be
removed from the spillway before the end of each work day. Disposal of debris and trash shall be at
an approved site.
B. Related Work Specified Elsewhere
1. Not Applicable
PART 2 - MATERIALS
1. The Contractor is responsible for all materials needed for any additional anchors on
the spillway walls to attach safety ropes and safety harness for use by their
employees, staff members of Paradise Irrigation District, staff members of Division
of Safety of Dams (DSOD), and/or representatives of the Consultant/Engineer
(GHD).
2. The Contractor is responsible for all materials and equipment needed to accomplish
the work described under PART 1 of this specification.
Paradise Irrigation District MAINTENANCE CLEARING OF DRAINS AND WEEPHOLES
Paradise Darn Spillway- Interim Risk Reduction Repair Item No. 1 - Page 1 of 3
GHD Project No. 12656399

3. The Contractor is responsible for all materials needed to implement Best
Management Practices (BMPs). The BMPs include preventing construction
materials, debris, trash, or sediment that come out of drains and weepholes during
cleaning process from entering water course downstream of the spillway structure.
PART 3 - SUBMITTALS
Submit the following list of documents for Engineer's review and comments at least seven
(7) calendar days to prior to start of work.
1. Work Plan for Best Management Practices.
2. Work Plan for Installation and Testing of Anchors on Spillway Walls, if additional
anchors are planned to be installed to accomplish the work.
3. Resumes of staff members/subcontractors who will perform the cleaning of drains
and weepholes.
4. Proposed equipment and tools to accomplish the work as well as to inspect the
progress of cleaning and to perform the final video inspection of the drains and
weepholes after cleaning is completed.
PART 4 - QUALITY ASSURANCE
A. The Contractor shall have personnel with at least 3 years of experience in careful cleaning
of drains and weepholes located in a spillway structure.
B. In case the Contractor does not meet the qualifications based on the above requirements,
acquire necessary onsite training from a qualified subcontractor prior to starting the
cleaning or the services of a qualified subcontractor must be utilized.
PART 5 - CONSTRUCTION REQUIREMENTS
A. The Contractor shall implement safety procedures at all times to meet Cal/OSHA (Division
of Occupational Safety and Health (DOSH) of California) Standards and Regulations..
B. The Contractor should be aware that access into the spillway chute will not be authorized
during storm events or spill events.
C. The Contractor is responsible for preventing debris, trash, or other materials from their
activities from entering water course downstream of the spillway structure. If there is any
deposition in the water course by the Contractor's activities, the Contractor is responsible
for removal and clean up in a timely manner.
D. Spoils/wastes may not be stockpiled or stored within the spillway structures and such
wastes shall be disposed of in conformance with all applicable codes and regulations. Any
spoils/wastes shall be cleaned/removed as soon as possible and before the end of each work
day.
Paradise Irrigation District MAINTENANCE CLEARING OF DRAINS AND WEEPHOLES
Paradise Darn Spillway- Interim Risk Reduction Repair Item No. 1 - Page 2 of 3
GHD Project No. 12656399

PART 6 - METHOD OF MEASUREMENT
1. The payment for cleaning of all drains and weepholes will be based on an
independent camera inspection of all drains and weepholes after completion of
the cleaning of drains and weepholes shown on the design drawings.
2. The lump sum bid price for Item 1 - Maintenance Cleaning of Spillway Drains
and Weepholes shall include the cost of all materials, equipment, and labor to
complete the work as specified in PART 1.
PART 7 - BASIS OF PAYMENT
1. The basis of payment will be based on successful completion of cleaning of all drains
and weepholes shown on the design drawings and as specified in PART 1.
END OF SECTION FOR ITEM 1
Paradise Irrigation District MAINTENANCE CLEARING OF DRAINS AND WEEPHOLES
Paradise Darn Spillway- Interim Risk Reduction Repair Item No. 1 - Page 3 of 3
GHD Project No. 12656399

ITEM 2 - JOINT REPAIR, CONCRETE DAMAGE REPAIR, AND
CRACK REPAIR CONSTRUCTION
PART 1 - GENERAL
A. Description
Following careful cleaning of the spillway chute slab and walls, the repair shall consist of the following
tasks:
* Repair of all joints in the spillway chute slab to include waterstops either using wider repair
of selected joints (please refer to Drawing ST-501 for further information regarding repair
procedures) or narrow repair of joints that are not actively seeping water and would have less
than four-inch-width following removal of any joint spalling on both sides of the joint using
Sika Products. Sika Hydrotite shall be used for repair of slots with a width of less than 34 inch,
Sika CJ-3030-M shall be used for repair of slots with a width between 34 inch and 1 inch, and
Sika Emseal shall be used for repair of slots with a width between 1 inch and 4 inches (please
refer to Drawing ST-502 for narrow repair details). After sawcutting as needed, deteriorated
concrete shall be removed in a manner that does not damage adjacent sound concrete. If
chipping hammers are used, the weight of the hammer shall not exceed 15 pounds.
* Repair of existing concrete damages (i.e. broken, cracked, spalled or otherwise considered
damaged concrete) on the spillway chute slab and walls that are shown on the drawings shall
be performed using similar repair approach to spillway joint repair (cleaning and dowels are
needed before patching the removed concrete area).
* Repair of existing cracks that are shown on the drawings using SikaFix HH+. All crack
repairs should be performed in accordance with instructions from the manufacturer and
general crack repair guidelines in the USACE (1995) publication, Evaluation and Repair of
Concrete Structures, EM 1110-2-2002.
Waterstops shall be placed at the bottom of the wider repair as shown on the drawing and shall be of
minimum six-inch preformed, dumbbell type waterstops fabricated of polyvinyl chloride (PVC) as
specified, 6 inches wide x 3/8 inch thick, Style 751, manufactured by Sika Corporation - Greenstreak
Division or approved equal. PVC waterstops shall be capable of resisting a minimum water head of
150 feet. Also, around the perimeter of the wider repair area, Hydrophilic WS, Greenstreak Hydrotite
Model CJ-3030-M or approved equal shall be placed as shown on the drawing.
As part of the cleaning needed before starting the repair work, all existing soil and accumulated debris
over the spillway slab and joint shall be carefully removed using brooming, vacuuming and very low
pressure compressed air or water jets. Any delaminated pieces of spillway slab will also need to be
removed as part of the preparation for the repair.
Approximate locations of all joints to be repaired, concrete damage to be repaired, and cracks to be
repaired are shown on the drawings. A few longitudinal cracks are present in the upper section
spillway slabs upstream of the bridge. A significant number of random cracks are present near the
center of each of the slab Panels 14 through 21 (please refer to drawings to understand the locations
Paradise Irrigation District JOINT REPAIR, CONCRETE DAMAGE REPAIR, AND CRACK REPAIR CONSTRUCTION
Paradise Darn Spillway- Interim Risk Reduction Repair Item No. 2 - Page 1 of 4
GHD Project No. 12656399

of these panels) in the steep portion of the spillway located downstream of the bridge and change in
slope at Station 14+50. These cracks are predominately in longitudinal and transverse directions with
some diagonal cracking. These cracks are not offset but are wider than hairline cracks. The depths of
these cracks are unknown. Any voids beneath the spillway slab identified during the crack repair
process shall be filled with Sika Grout 212 grout before filling and sealing of the cracks using
recommended procedures.
The Contractor shall implement safety procedures at all times to meet Cal/OSHA Standards and
Regulations. The Contractor should be aware that access into the spillway chute will not be authorized
during storm or spill events. The Contractor is responsible for preventing debris, trash, or other
materials from their activities from entering the water course downstream of the spillway structure. If
there is any deposition in water course by the Contractor's activities, the Contractor is responsible for
removal and clean up in a timely manner. All debris and trash removed from drains and weepholes
and concrete debris shall be removed from the spillway before the end of each work day. Disposal of
debris and trash shall be at an approved site.
B. Related Work Specified Elsewhere
1. Not Applicable
PART 2 - MATERIALS
1. The Contractor is responsible for all materials needed for any additional anchors on
the spillway walls to attach safety ropes and safety harness for use by their
employees, staff members of Paradise Irrigation District, staff members of Division
of Safety of Dams (DSOD), and/or representatives of the Consultant/Engineer
(GHD).
2. The Contractor is responsible for all materials and equipment needed to accomplish
the work described under PART 1 of this specification.
3. The Contractor is responsible for all materials needed to implement Best
Management Practices (BMPs). The BMPs include preventing construction
materials, debris, trash, or sediment that come out of drains and weepholes during
cleaning process and concrete debris materials from entering water course
downstream of the spillway structure.
PART 3 - SUBMITTALS
Submit the following list of documents for Engineer's review and comments at least seven
(7) calendar days to prior to start of work. A few of the same submittals are listed under
Item 1 as well, so submittal related to Items 1 and 2 can be combined into one submittal.
1. Work Plan for Best Management Practices.
2. Work Plan for Installation and Testing of Anchors on Spillway Walls, if additional
anchors are planned to be installed to accomplish the work.
Paradise Irrigation District JOINT REPAIR, CONCRETE DAMAGE REPAIR, AND CRACK REPAIR CONSTRUCTION
Paradise Darn Spillway- Interim Risk Reduction Repair Item No. 2 - Page 2 of 4
GHD Project No. 12656399

3. Resumes of staff members/subcontractors who will perform the joint repair, concrete
repair and crack repair.
4. Proposed equipment and tools to accomplish the work.
5. Current specifications from the manufacturer for the products to be used for the repair.
PART 4 - QUALITY ASSURANCE
A. The Contractor shall have personnel with at least 3 years of experience in performing the
joint repair, concrete repair and crack repair in a spillway structure.
B. In case the Contractor does not meet the qualifications based on the above requirements,
acquire necessary onsite training from a qualified subcontractor prior to starting the repair
work or the services of a qualified subcontractor must be utilized.
PART 5 - CONSTRUCTION REQUIREMENTS
A. The Contractor shall implement safety procedures at all times to meet Cal/OSHA (Division
of Occupational Safety and Health (DOSH) of California) Standards and Regulations..
B. The Contractor should be aware that access into the spillway chute will not be authorized
during storm events or spill events.
C. The Contractor is responsible for preventing debris, trash, or other materials from their
activities from entering the water course downstream of the spillway structure. If there is
any deposition in the water course by the Contractor's activities, the Contractor is
responsible for removal and clean up in a timely manner.
D. Spoils/wastes may not be stockpiled or stored within the spillway structures and such
wastes shall be disposed of in conformance with all applicable codes and regulations. Any
spoils/wastes shall be cleaned/removed as soon as possible and before the end of each work
day.
PART 6 - METHOD OF MEASUREMENT
1. The payment for Joint Repair, Concrete Damage Repair, and Crack Repair will be
based on final inspection of the completed repair and approval by the Engineer.
All joint repair, concrete repair, and crack repair as shown on the drawings should
be completed before requesting the Engineer to perform the final inspection.
2. The lump sum bid price for Item 2 - Joint Repair, Concrete Damage Repair, and
Crack Repair Construction shall include the cost of all materials, equipment, and
labor to complete the work as specified in PART 1.
Paradise Irrigation District JOINT REPAIR, CONCRETE DAMAGE REPAIR, AND CRACK REPAIR CONSTRUCTION
Paradise Darn Spillway- Interim Risk Reduction Repair Item No. 2 - Page 3 of 4
GHD Project No. 12656399

PART 7 BASIS OF PAYMENT
1. The basis of payment will be based on successful completion of Item 2 - Joint
Repair, Concrete Damage Repair, and Crack Repair as specified in PART 1 and
related details and procedures shown on drawings.
END OF SECTION FOR ITEM 2
Paradise Irrigation District JOINT REPAIR, CONCRETE DAMAGE REPAIR, AND CRACK REPAIR CONSTRUCTION
Paradise Darn Spillway- Interim Risk Reduction Repair Item No. 2 - Page 4 of 4
GHD Project No. 12656399