71 EXISTING DRAINAGE FACILITIES
71-1 General
71-1.01 General
Section 71 -1 includes general specifications for performing work on existing drainage facilities . Drainage faci lities include culverts, inlets, headwalls, endwalls, aprons, drains, pipes, gutters, gutter depressions, junction structures, spillways, and check dams.
71-1.02 Materials
Temporary pipe plug must be one of the following:
1.Wall of minor concrete not les s than 6 inches thick
2.Tight brick wall not less than 8 inches thick with cement mortar joints
3.Commercially -manufactured plug if its use is required for less than 6 months
71-1.03 Construction
Trenches, holes, depressions, and pits caused by removin g, salvaging, reconstructing, abandoning, destroying, modifying, resetting, relocating, adjusting, relaying, remodeling, and rehabilitating highway facilities must be backfilled with embankment material under section 19. If the trenches, holes, depressions , and pits are in surfaced areas that remain undisturbed, backfill with material that is equal or better in quality and to the thickness of the surrounding materials. Where partial removal of reinforced concrete is required, remove a sufficient volume of c oncrete to expose the reinforcement for splicing. Splicing must comply with section 52. Clean off material adhering to the reinforcement before placing new concrete.
71-1.04 Payment
Not Used
71-2 Remove Drainage Facilities
71-2.01 General
71-2.02 Materials
Not Used
71-2.03 Construction
Box culverts, inlets, headwalls, and endwalls must be completely removed if any portion of these structures is (1) within 3 feet of the grading plane in excavation areas, (2) within 1 foot of original ground in embankment areas, or (3) shown to be removed. Except for concrete pipe, removing PCC components of drainage facilities must comply with section 15 - 1.03B. Reuse frames, grates, and covers at the locations shown.
71-2.04 Payment
Payment for removing and reusing frames, grates, and covers is included in the payment for the various items of work that include the re used frames, grates, and covers.
71-3 Rehabilitate Drainage Structures
71-3.01 General
71-3.01A General
71-3.01A(1) Summary
Section 71 -3 includes specifications for cleaning and preparing, inspecting and evaluating, repairing, rehabilitating, and reins pecting culverts. Storm drains, pipes, conduit, risers, downdrains, median drainage inlets, and underdrains are included in the work under section 71 -3 if they are attached t o the culvert. SECTION 71 EXISTING DRAINAGE FACILITIES Repair as described. Repairing includes:
1.Filling voids below and around the exterior of the culverts
2.Restoring culvert openings
3.Smoothing protrusions inside culverts Rehabilitate as described. Rehabilitating includes:
1.Filling vo ids below and around culverts
2.Paving culvert inverts
3.Installing pipeliners inside culverts For a miscellaneous drainage component with alternative in the bid item description, choose from the types of the component shown. Do not mix different types of the same component in the same location.
71-3.01A(2) Definitions
alternative pipeliner: Bid items used where more than one type of pipeliner is shown for a given culvert. annular space: Space or void between the outside wall of the pipeliner and the inside wall of a culvert. lateral pipe opening: Opening in a culvert for a connecting pipe or drain of any kind. service opening: Opening in a culvert for maintenance, repair, inspection, or cleaning. wastewater: Water and contaminants generated by culvert rehabilitation. waterway: Existing drainage system, including surface water, tributaries, and groundwater.
71-3.01A(3) Submittals
Reserved
71-3.01A(4) Q uality Assurance
71-3.01A(4)(a) General
Use an authorized laboratory with staff experienced and capable of conducting the specified testing. Your staff that performs inspections must be trained and experienced in locating defects, breaks, and obstacles.
71-3.01A(4)(b) Preconstruction Meetings
71-3.01A(4)(b)(i) General
Reserved
71-3.01A(4)(b) (ii) Prerehabilitation Meeting
Before starting cleaning and preparation work, you must schedule and attend a prerehabilitation meeting with the Engineer. Include any subcontractors, manufacturers and other parties involved in the culvert work. Provide a meeting facility that is within 5 miles of the job site or at another location accepted by the Engineer.
71-3.01A(4)(b) (iii) Pregrouting Meeting
Before starting grout ing work, you must schedule and conduct a grouting meeting with the Engineer and your personnel involved in the grouting work, including your:
1.Project superintendent
2.Supervisory personnel
3.Grouting foreman
4.Grouting subcontractors Provide a meeting facility that is within 5 miles of the job site or at another location accepted by the Engineer. SECTION 71 EXISTING DRAINAGE FACILITIES
71-3.01A(4)(c) Quality Control
71-3.01A(4)(c)(i) General
Reserved
71-3.01A(4)(c) (ii) Annular Space Grouting
The grout cast density at the point of p lacement must be from 53 to 68 lb/cu ft and the minimum compressive strength must be 300 psi at 28 days. Test the grout for compressive strength under ASTM C495 except that specimens must be moist cured before the 28 -day compressive strength test and not b e oven dried. If the grouting plan shows multiple stages, the grouting plan must include test results that verify that the grout stiffness is adequate for placement of multiple lifts. For each batch of grout, perform density and viscosity tests under ASTM C138 and ASTM C939 in the presence of the Engineer. Grout density must be within 3 lb/cu ft of the density in the authorized grout plan with mix design. The time of efflux (outflow) must not exceed 20 seconds as specified in ASTM C939 unless otherwise auth orized. For pipeliners with a stiffness of less than 29 psi, the grout pump's pressure measured at the point of injection must not exceed either of the following:
1.5 psi
2.Manufacturer's instruction For pipeliners with a stiffness of at least 29 psi, t he grout pump's pressure measured at the point of injection must not exceed 7.25 psi. The pipeliner must be able to withstand a static head of grout that is 6 inches above the highest crown elevation. The maximum grout pressure for a static grout head must not exceed the grout pump's maximum allowable pressure. Install a grout pressure gauge and recorder immediately adjacent to each injection port. Continuously record on paper with ink the actual grouting pressure versus time. Record grout pressure to an ac curacy of ±0.5 psi. Attach a gauge to a saddle -type diaphragm seal to prevent clogging with grout.
71-3.01A(4)(c) (iii) CCTV Recording
CCTV recordings must be made and submitted in high quality electronic media such as CD or DVD. The CCTV equipment must in clude:
1.CCTV camera with articulating head
2.Transporter adapted for conditions of the culvert
3.Television monitor
4.Lighting
5.Cables and power sources CCTV equipment must:
1.Be specifically designed and constructed for pipe inspection
2.Have ca mera lighting for minimizing reflective glare
3.Have an adjustable focal -distance range from 6 inches to infinity
4.Produce a minimum resolution of 356 lines per inch for both the camera and monitor
5.Have a remote -reading meter counter accurate to 1 percent over the length of the particular section being inspected Verify the accuracy of the distance meter in the CCTV with a walking meter, roll -a-tape, or other authorized device. Where human entry is possible for the entire length of the culvert, you may use a handheld video camera with lighting as an alternative to CCTV. Video and audio content must comply with the requirements for CCTV. Inspect at a rate that is not more than 30 feet per minute. SECTION 71 EXISTING DRAINAGE FACILITIES
71-3.01A(4)(c) (iv) Photographs
Use a digital camera and lighting. Lighting and photo quality must be suitable to provide clear and focused photographs of the entire culvert surface under all conditions.
71-3.01A(4)(c) (v) Monitoring of Annular Space Grouting
Wherever a pipeliner with annular space gr outing is described, monitor the grouting and record pressures throughout the grouting process. Verify compliance with the manufacturer's instructions for each phase of the grouting process. Gauges must comply with ANSI B40, Grade 2A. The pressure gauges, recorder, and field equipment must be calibrated by an independent testing agency.
71-3.01A(4)(c) (vi) Pipeliners
Pipeliners must be continuous over the entire length of the culvert and must have no visual defect such as foreign inclusions, concentrated ri dges, discoloration, pitting, pin holes, cracking or other deformities. The pipeliner must not be over -deflected. There must not be segregation or voids in the grout.
71-3.01A(4)(c) (vii) Deflection Testing of Pipeliners
If a pipeliner with annular space g routing is described, test the pipeliner for deflection. Test after grouting and in the presence of the Engineer. For pipeliners with a nominal inside diameter of 36 inches or less, either pull a mandrel through the pipeliner by hand or use another authori zed method. The mandrel must be:
1.Rigid and nonadjustable
2.Comprised of at least 9 legs and have an odd number of total legs
3.Longer than it is wide
4.Made of steel
5.Fitted with pulling rings at each end
6.Stamped or engraved on some segment othe r than a runner indicating pipeliner material specification, nominal size, and mandrel outside diameter (e.g., HDPE F 714 -SDR 26 -36" – 31.569")
7.Furnished in a suitable carrying case labeled with the same data as stamped on the mandrel
8.Authorized bef ore use For pipeliners with a nominal inside diameter greater than 36 inches, determine the deflection using a 1 - inch diameter, rigid, nonadjustable metal bar; a minimum -radius rigid template; or other authorized method. The pipeliner must not be over -deflected. For pipeliners 36 inches or less in nominal diameter, the mandrel must pass through the entire pipeliner. For pipeliners greater than 36 inches in nominal diameter, the deflection must be the lesser of either of the following:
1.5 percent greater than the actual dimension of the pipeliner in place. This actual dimension includes the pipe joint system.
2.6-1/2 percent of the nominal pipeliner dimension. If more than 8 percent of the nominal pipeliner dimension is over -deflected, the pipeliner is rejected. If 8 percent or less of the nominal pipeliner dimension is over -deflected, the pipeliner may remain in place and the Department deducts 20 percent of the bid amount for that pipeliner.
71-3.01B Materials
71-3.01B(1) General
Slurry cement backfill for culverts must comply with s ection 19 -3.02E .
71-3.01B(2) Contact Grout
Grout for contact grouting must comply with section 41 -2 and contain:
1.Not more than 2 percent bentonite by weight of cement and water
2.Not less than 590 lb of c ementitious material per cubic yard If sand is used in the grout mix, the sand must comply with section 90 -1.02C(3) and the gradation requirements in the following table: SECTION 71 EXISTING DRAINAGE FACILITIES Sieve size Percent passing No. 8 100 No. 16 95–100 No. 30 60–85 No. 50 20–50 No. 100 10–30 No. 200 0–20
71-3.01B(3) Annular Space Grout
Grout for annular space grouting must be low -density foam concrete that consists of water, cementitious materials, foaming agent, and optional chemical admixtures. Cementitious materials must comply with section 90 -1 except:
1.Use of SCM is not mandatory
2.You may only use SCM if you submit a statement from the foaming agent's manufacturer verifying that the foaming agent is compatible with the SCM Foaming agent m ust comply with ASTM C869.
71-3.01C Construction
71-3.01C(1) General
Comply with the following work sequence and notify the Engineer before you start each of the following steps:
1.Clean and prepare
2.Inspect and evaluate
3.Repair culvert
4.Rehabilitate culvert
5.Restore openings
6.Perform post -rehabilitation inspection Before starting the inspection, the culvert must be clean and free of water and debris. During all culvert work, keep the culvert clean and free of water and debris. Wherev er culvert struts are described in the grouting plan, install struts before starting any grouting. Wherever structural concrete repairs to the culvert are shown or ordered, the structural concrete repair must be complete and the concrete must have a compre ssive strength of at least 2,500 psi before starting any grouting. Wherever concrete invert paving is shown or ordered, the invert paving must be complete and the concrete paving must have a compressive strength of at least 2,500 psi before starting any gr outing.
71-3.01C(2) Cleaning and Preparation
Remove all debris, sediment, and other accumulated material from the culvert invert and restore the flow area to the original flow area or to the diameter shown. Where shown, disconnect down drains towards the downstream end of the culvert. Clean the culvert with high -velocity cleaning equipment and air mover or mechanically powered equipment. If human entry is possible, you may use nonmechanically powered cleaning equipment.
71-3.01C(3) Inspection and Evaluati on
After cleaning and preparation is complete, inspect the entire length of the culvert and submit the inspection and evaluation report. Inspect by either CCTV or human entry. If sediment, debris, or other accumulated material is found during inspection, s top the inspection and reclean the culvert. Cleaning must comply with the manufacturer's instructions for the type of pipeliners SECTION 71 EXISTING DRAINAGE FACILITIES shown. Cleaning must be complete to allow accurate CCTV and photography of the entire culvert. No payment is made for recleanin g. Make a 360 -degree inspection, video, and photographic record of each joint and lateral joint. If the CCTV camera does not pass from one end of the culvert through the entire length of the culvert, reset the equipment and inspect from both ends until the entire length is documented. If the inspection video is low quality and does not adequately depict the condition of the culvert, correct the deficiencies and reinspect the culvert. Low quality may result from:
1.Poor camera head position
2.Poor focus
3.Low lighting
4.Rapid rate of progression
5.Missing documentation of time and location
6.Inadequate cleaning of the culvert No payment is made for reinspection due to low quality and recleaning.
71-3.01C(4) Repairing
After obtaining authorization of the inspection and evaluation report, repair the existing culvert as described or ordered. Complete repairs before starting rehabilitation work.
71-3.01C(5) Rehabilitation
71-3.01C(5)(a) General
Place slurry cement backfill around the cu lvert and below the culvert invert as shown.
71-3.01C(5)(b) Annular Space Grouting
Before starting grouting activities, install the bulkheads and place grout injection tubes and breather tubes with removable plugs around the pipeliner and through bulkhead s as shown in the authorized grouting plan. Grout the entire annular space between the pipeliner and culvert without voids or grout segregation. If you determine, before starting grouting, that the entire annular space is not accessible for grouting, submi t a work plan for correcting the annular space to allow for grouting. No payment is made for correction of the annular space to allow for grouting. Mix the water, cementitious materials, and chemical admixtures before adding the foaming agent to the grout. Add the foaming agent at the job site. Grout must be placed in a continuous manner and injected in lifts. The height of the lifts must (1) not exceed the height in the authorized grout plan or (2) be less if needed to avoid floating, shifting, or deformin g the pipeliner. Monitor the injection pressure, including the pressure for the last lift at the crown. If the pipeliner cannot withstand grouting pressures or static head, either reduce the maximum pressure at the point of grout injection, or employ stage d grouting.
71-3.01C(5)(c) Restoring Openings
Within 72 hours of installing a pipeliner, restore the lateral pipe and service openings, risers, downdrains, median drainage inlets, and underdrains. Restore these openings before starting pipeliner installat ion at another culvert location. The openings must conform and match the invert of connecting pipes. Do not excavate unless authorized. Restore openings from the interior of the pipe. Use either a CCTV and remote -control cutting device or human entry. The area of the restored opening must be at least 95 percent of the original area. Openings must have an edge that is crack -free, smooth, and free of burrs and projections. SECTION 71 EXISTING DRAINAGE FACILITIES Where human entry is possible, grout the restored opening so that the seal is watertigh t. Grout must be one of the following:
1.Quick -set epoxy mortar
2.High-viscosity epoxy
3.Hydrophilic vulcanized expansive rubber strip
4.Manufacturer's recommended mix
71-3.01C(5)(d) Postrehabilitation Inspection
Postrehabilitation inspection m ust co mply with section 71 -3.01C(3) .
71-3.01D Payment
Payment for the following work is included in the payment for cleaning, inspecting, and preparing the culvert:
1.Cleaning and preparation
2.Quality control and assurance
3.Keeping the culvert free of water and debris
4.Inspection and evaluation
5.Performing postrehabilitation inspection Unless a separate pay item is described for diverting the culvert flow, payment for diverting the flow of water away from the culvert is included in the payment for cleaning, inspecting, and preparing the culvert. Repairs, additional cleaning, disconnecting downdrains, and reconnecting down drains are paid as change order work unless such work is described in the Contract. Record the quantity of slurry cement backfill that is installed in the culvert and submit this quantity. The Department does not pay for slurry cement backfill material that is wasted, disposed of, or remaining on hand after the completion of the work. Record the quantity of grout that is installed a nd submit this quantity. The Department does not pay for grout that leaks through to the inside of the culvert. The Department does not pay for grout material that is wasted, disposed of, or remaining on hand after the completion of the work. Pipeliners ar e measured along the flow line of the existing culvert. No payment is made for pipeliner length in excess of the measured length.
71-3.02 Fill Culvert Voids
Reserved
71-3.03 Contact Grouting
Reserved
71-3.04 Invert Paving
Reserved
71-3.05 Epdm Rubber P Ipe Joint Seal
Reserved
71-3.06 Welded Steel Pipeliners
Reserved
71-3.07 Plastic Pipeliners
Reserved
71-3.08 Cured -In-Place Pipeliners
Reserved SECTION 71 EXISTING DRAINAGE FACILITIES
71-3.09 Machine Spiral Wound Pvc Pipeliners
71-3.09A General
71-3.09A(1) General
71-3.09A(1)(a) Summary
Section 71 -3.09 includes specifications for installing machine spiral wound PVC pipeliners directly into the culvert.
71-3.09A(1)(b) Definitions
Reserved
71-3.09A(1)(c) Submittals
Submit a certificate of compliance for each reel of PVC strip and include:
1.Name of the manufacturer
2.Plant location
3.Date of manufacture and shi ft
4.Cell classification
5.Unit mass
6.Average pipeliner stiffness and profile type
71-3.09A(1)(d) Quality Assurance
Reserved
71-3.09A(2) Materials
Each reel and continuous PVC strip must be distinctively marked on the inside surface, at intervals no t exceeding 5 feet, and with a coded number. The coded number must include:
1.Name of the manufacturer
2.Plant location
3.Date of manufacture and shift
4.Minimum strip thickness
5.Cell classification and profile type
6.Size The marking must be visible from inside the completed pipeliner.
71-3.09A(3) Construction
Restore openings.
71-3.09A(4) Payment
Not Used
71-3.09B Machine Spiral Wound PVC Pipeliners, Grouted
71-3.09B(1) General
71-3.09B(1)(a) Summary
Section 71 -3.09B includes specificati ons for installing a continuous spiral wound PVC pipeliner into the interior of an existing culvert and filling the annular space with grout. The pipeliner must be wound directly into the culvert using equipment that is either self running or static. Where human entry is feasible, the pipeliner may be wound by hand inside the culvert.
71-3.09B(1)(b) Definitions
Reserved
71-3.09B(1)(c) Submittals
If you use pressure for installing the pipeliner, the annular space grouting plan must include:
1.Manufacturer 's instructions for the maximum internal pressure
2.Maximum differential pipeliner pressures SECTION 71 EXISTING DRAINAGE FACILITIES
71-3.09B(1)(d) Quality Assurance
The nominal dimensions for the pipeliner must comply with dimensions shown.
71-3.09B(2) Materials
PVC profile strips must comp ly with ASTM F1697 or ASTM F1735. You may use alternative profile types and corresponding minimum properties if authorized.
71-3.09B(3) Construction
Pipeliner installation must comply with ASTM F1741 or ASTM F1698. The profile strip may be nonreinforced o r reinforced with a continuous -profiled steel strip with interlocking edges. Sealants and gaskets necessary for effectively interlocking the edges of the profile strip must be pre -applied at the time of manufacture. Lock edges together as the strip is woun d into the culvert. If the profile strip is reinforced, mechanically lock the profiled steel band onto the outside of the PVC pipeliner. For circular culverts, wind the profile strip at a fixed diameter. For noncircular culverts, wind the profile strip at a fixed dimension. Leave an annular space between the pipeliner and culvert wall. The ends of the pipeliner must be flush with the culvert unless a beveled end is shown. After grouting and beveling where shown, seal the ends of the culvert between the pipe liner and culvert with cement mortar under section 65 -2.02F.
71-3.09B(4) Payment
Not Used
71-3.09C Machine Spiral Wound PVC Pipeliners, Expandable Diameter
71-3.09C(1) General
Section 71 -3.09C includes specifications for installing a continuous spiral wound pipeliner into the interior of an existing culvert and expanding the pipeliner radially against the culvert.
71-3.09C(2) Materials
PVC profile strips must comply with ASTM F1697.
71-3.09C(3) Construction
Pipeliner installation mus t comply with ASTM F1741. The pipeliner must be continuous over the entire length of the insertion. Install PVC strips directly into the culvert from an insertion point and expand the strips radially against the culvert after insertion. Sealants and gasket s necessary for effectively interlocking the edges of the profile strip must be pre - applied at the time of manufacture. Lock edges together as the strip is wound into the culvert. Seal the ends of the culvert between the pipeliner and culvert with cement m ortar under section 65 -2.02F.
71-3.09C(4) Payment
Not Used
71-3.10 Cementitious Pipeliners
Reserved
71-3.11 71-3.15 Reserved
71-4 Modify Drainage Structures
71-4.01 General
71-4.01A General
Section 71 -4 includes specifications for partially removing, adjusting, and adding to drainage facilities.
71-4.01B Materials
Not Used SECTION 71 EXISTING DRAINAGE FACILITIES
71-4.01C Construction
Not Used
71-4.01D Payment
Not Used
71-4.02 Pipes
71-4.02A General
Modifying pipes includes extending pipes. Extending pipes must comply with the specifications for new pipe installation.
71-4.02B Materials
Not Used
71-4.02C Construction
Existing headwalls or end walls must be removed or moved to a new location. If headwalls or end walls ar e to be moved, cut the pipe so that it has smooth edges at a point approximately 1 foot behind the headwall or end walls and perpendicular to the centerline of the pipe. Move the headwall or end wall to the reconstructed location and connect the pipes.
71-4.02D Payment
Not Used
71-4.03 Inlets, Manholes, and Risers
71-4.03A General
Not Used
71-4.03B Materials
Not Used
71-4.03C Construction
Modify inlet, manhole, and riser structures as shown. Excavate and remo ve structures to a depth of at least 1 foot below the grading plane. Cap inlet structures with minor concrete. Where shown, round the bottom of structures with minor concrete. Minor concrete must contain at least 590 pounds of cementitious material per cub ic yard. Backfill to match the grading plane .
71-4.03D Payment
Not Used
71-4.04 Slotted Pipe Grate
Reserved
71-5 Adjust Drainage Structures
71-5.01 General
Section 71 -5 includes specifications for partially removing and either lowering or raising facilities. Adjust to grade with new materials that are similar in character to the existing materials.
71-5.02 Materials
Not Used
71-5.03 Construction
71-5.03A General
Reserved SECTION 71 EXISTING DRAINAGE FACILITIES
71-5.03B Frames, Covers, and Gr ates
Adjust frames, covers, and grates must comply with section 78-23.03.
71-5.03C Inlet
Adjust inlets as shown. Use minor concrete with at least 590 pounds of cementitious material per cubic yard. Where inlets are adjusted before placing the uppermost layer of pavement or surfacing, limit the work area so that adjusting the inlet and final paving or surfacing is completed within the same workday. The top of the inlet grate or cover must be protected during paving operations by heavy plywood covers, steel plate covers, or other authorized methods. Excess paving material must be removed before rolling. Where inlets are adjusted after placing the uppermost layer of pavement or surfacing, do not adjust the inlet to final grade un til the paving or surfacing has been completed immediately adjacent to the inlet.
71-5.04 Payment
If adjust inlet is paid by the linear foot, adjusting the inlet is measured as the difference in the length between the top of the existing inlet and the top of the adjusted inlet.
71-6 Abandon Drainage Structures
71-6.01 General
71-6.01A General
Section 71 -6 includes specifications for partially removing and rendering facilities unserviceable in place. Wherever manholes or drainage facilities are abandoned, pipes entering the manhole or drainage facility must be securely closed by a tight -fitting plug that is either of the following:
1.Wall of minor concrete not less than 6 inches thick
2.Tight brick wall not less than 8 inches thick with cement mortar joints The bases of manholes or drainage facilities must be broken so that water is prevented from being entrapped. Demolish the manhole or drainage facility to an elevation that is 3.5 feet below finished grade. Backfill must comply with section 19 -3.03E.
71-6.01B Materials
Not Used
71-6.01C Construction
Not Used
71-6.01D Payment
Not Used
71-6.02 Manholes
Reserved
71-6.03 Culverts and Pipelines
Reserved
71-6.04 Inlets
Reserved
71-6.05 71-6.15 Reserved
71-7 Salvage Drainage Facilities
71-7.01A General
Section 71 -7 includes specifications for salvaging drainage facilities. Salvage drainage facilities as shown. SECTION 71 EXISTING DRAINAGE FACILITIES
71-7.01B Materials
Not Used
71-7.01C Construction
Not Used
71-7.01D Payment
Not Used
71-8 71-15 Reserved
Source: California Standard Specifications, 2024 Edition. Pages 1023–1034 of 1,372.