Division VII — Drainage Facilities
61 GENERAL
61-1 General
61-1.01 General
Section 61 includes general specifications for constructing drainage facilities.
61-1.02 Materials
Not Used
61-1.03 Construction
Not Used
61-1.04 Payment
Not Used
61-2 Culvert and Drainage Pipe Joints
61-2.01 General
61-2.01A Summary
Section 61 -2 includes specifications for con structing joint systems and couplers for culverts and drainage pipes . Joint systems and couple rs for culverts and drainage pipes are classified as standard, positive, or downdrain.
61-2.01B Definitions
shear strength : Required joint shear strength expressed as a percentage of the calculated pipe shear strength at a transverse section remote from t he joint. moment strength : Moment strength required of the joint expressed as a percentage of the calculated moment capacity of the pipe on a transverse section remote from the joint. tensile strength : Resistance to the longitudinal force that tends to sep arate adjacent pipe sections. integral joint overlap : Projection of 1 pipe barrel into another pipe barrel. sleeve joint overlap : Minimum sleeve width required to engage abutted pipe barrels. watertightness : Ability of a joint to hold water under pressure without leaking. joint: Connection point for 2 or more pipe sections.
61-2.01C Submittals
For watertight joints, submit your analysis or test results performed on representative joints proposed for installa tion. Submit a certificate of compliance for each classification of joint systems and couplers. Where field leakage testing is shown for pipe systems, submit:
1.Proposed field leakage test procedure for each portion of each pipe system at least 15 days be fore you start testing. The submittal for each proposed field leakage test procedure must include: 1.1. Type of test: exfiltration, low -pressure air, negative air pressure, or other authorized method 1.2. Specific joints or pipe sections to be tested 1.3. Maximum and minimum pressures or hydrostatic head to be applied 1.4. Duration of tests from location to location 1.5. Date and time of each test 1.6. List of test equipment to be used 1.7. Date of last calibration if applicable
2.Leakage calculations for the exfiltration and infiltration tests
3.Repair procedure for joints or pipe sections that fail the field leakage test SECTION 61 GENERAL
61-2.01D Quality Assurance
61-2.01D(1) General
Reserved
61-2.01D(2) Quality Control
61-2.01D(2)(a) General
Reserved
61-2.01D(2)(b) Watertightness Test
Perform watertightness tests of the assembled joints. The assembled joints must pass the tests without joint leakage. The watertightness test must consist of testing the hydrostatic pressure on a joint by connecting 2 pipe sectio ns under the manufacturer's instructions. Provide suitable bulkheads within the pipe adjacent to and on either side of the joint or at the outer ends of the joined pipe sections. Do not place mortar or concrete coating, filling, or packing in addition to t hat normally required for the joint before conducting the watertightness test. After the pipe sections are fitted together with the gasket or gaskets in place, subject the assembly to a 10 -foot water pressure head above the pipe crown for 10 minutes. Moist ure or beads of water appearing on the surface of the joint are not considered leakage. Perform the test on individual joints at the manufacturer's plant. Test joint watertightness on pipe sections in straight alignment and on pipe sections deflected from straight alignment. When you test joints on pipe sections not in straight alignment, position the pipe sections to create a gap on one side of the outside pipe perimeter that is 1/2 inch wider than the gap for the pipe sections in straight alignment. If yo u use coupling bands to test the pipe sections not in straight alignment and the maximum gap on one side of the outside pipe perimeter is less than 1/2 inch wider than that for the pipe sections in straight alignment, position the coupling band and the pip e sections to provide the maximum gap.
61-2.01D(2)( c) Performance Specifications
For joint systems and couplers under section 61 -2.01D(2)( c), determine the values for joint properties by mathematical analysis or an authorized test . Joint components subject to bending forces must not be stressed beyond the minimum specified yield strength of the material as determined by using the plastic section modulus. Joint systems or couplers must:
1.Perform their intended function
2.Possess durability equivalent to that of the pipe
3.Comply with the quality characteristics shown in the following table: SECTION 61 GENERAL Joint Classification Requirements Quality characteristic Requirement Standard Positivea Downdrainb Shear strength (min, %) 2 5 5 Moment strength (min, %) 0 15 15 Tensile strength : 6"–42" diac (min, lb) 0 0 5,000 45"–84" diac (min, lb) 0 0 10,000 Joint overlapd Integral : 12" and smaller diae (min, in) 1/4 1/2 -- 15"–33" diae (min, in) 1/2 3/4 -- 36" and larger diae (min, in) 3/4 1 -- Sleeve width (min, in) 10-1/2 10-1/2 10-1/2 Watertightness Where described Where described Required aPositive joints must comply with either (1) shear strength, moment strength, and joint overlap -sleeve properties, or (2) shear strength and joint overlap -integral characteristics. bJoints for downdrains have at least the specified values when tested with joints sealed to comply with the watertightness requirement. cLimits for corrugated metal pipe arch depend upon the equivalent diameter of circular pipe under AASHTO M 36 for corrugated steel pipe and AASHTO M 196 for corrugated aluminum p ipe. dJoints designed to comply with required values by means other than joint overlap as shown in the table may be used if authorized. eInside diameter of circular pipes or inside horizontal dimension of oval or arch pipes.
61-2.01D(3) Field Leakage Te sting
61-2.01D(3)(a) General
Perform field leakage testing on culverts and drainage structures wherever field leakage testing is shown. Field leakage testing includes:
1.Cleaning and presoaking pipes
2.Installing and removing bulkheads or plugs necessar y to perform tests
3.Removing and disposing of waste materials
4.Retesting
5.Repairing
6.Changing the drainage system to comply with specifications for field leakage testing For pipe systems less than 1,500 feet in length, test all joints for leakage. For pipe systems 1,500 feet or greater in length, test each pipe system for leakage at locations selected by the Engineer at a rate of:
1.50 joints per 100 pipe joints for pipe systems less than 1 mile in length
2.30 joints per 100 pipe joints f or pipe systems from 1 mile to 3 miles in length
3.20 joints per 100 pipe joints for pipe systems more than 3 miles in length For every selected joint or section that fails leakage requirements, the Engineer may select up to 4 more joint locations or sec tions between joints for testing. Clean the pipe and remove debris and sediment before you start testing. SECTION 61 GENERAL Clean and test each pipe system and appurtenances by using the exfiltration, infiltration, low -pressure air, or negative air pressure method, except t he Engineer must approve the use of the infiltration test if the groundwater table is low. You may test installed pipe joints using air or water under low pressure. Field leakage testing is conducted after backfilling. Do not use your test equipment until it is authorized. The Engineer may require a calibration test of gauges or other instrumentation. Use only 1 leak test method on a contiguous pipe system unless the pipe type or diameter changes in the same run. Complete the cleaning and testing of each pi pe system between inlets or ends within 20 days after backfilling for storm drain lines and structures. Perform each test in the presence of the Engineer. Prevent joints from separating during a test. Repair any damage resulting from the field leakage test . Take corrective action and retest the line if the leakage exceeds the allowable quantity. Determine the leak source and repair or replace the defective pipe whenever an installed pipe system fails to comply with the requirements under the test method use d. The Engineer does not accept a pipe installation if it fails to pass the field leakage test. Stop all obvious leaks even if the leakage is below the allowable quantity.
61-2.01D(3)(b) Exfiltration and Infiltration Testing
Exfiltration and infiltration tests must comply with ASTM C969 except:
1.You may fill the pipe with clear water to allow normal absorption into the pipe wall before performing the exfiltration leakage test. Start the leakage test within 72 hours after filling the pipe and complete the field leakage test within 24 hours thereafter. The test period must be at least 1 hour in duration. For plastic and metal pipe, the absorption period is not required.
2.Leakage must not be more than 1,000 gallons per inch of nominal pipe diameter per mile of pipe per day with a minimum test pressure of 6 feet of water column above the pipe crown at the upper end of the pipe or above the active groundwa ter table, whichever is higher. Limit the length of pipe you test such that the pressure on the invert of the lower end of the section does not exceed 20 feet of water column. Increase the allowable leakage by 8 percent for each increase in pressure of 1.5 feet above the basic 6 -foot water column measured above the crown or at the lower end of the section.
3.Whenever a suitable head of groundwater exists above the pipe crown and if the pipe is large enough to work inside, the Engineer may accept the instal led pipe on the basis of visible leakage repair during the infiltration leakage test.
4.Take into account all lateral or side storm drains included in the test section in computing the allowable leakage. Make an allowance of 0.2 gallons per hour per foot of head above the invert for each junction structure or drainage inlet included in the test section. Storm drains, side storm drains, and fittings must be open, clean, and free draining upon final completion of the work.
61-2.01D(3)(c) Low -Pressure Air T est
You may use the low -pressure air test instead of the exfiltration test or the infiltration test for pipes 30 inches in nominal diameter or less. You may prewet the pipes. Test pipes f rom inlet to inlet or shorter lengths. Do not use the low -pressure air test for drainage pipes over 30 inches in nominal diameter regardless of the material type. If you use a low -pressure air test, perform the test immediately following pipe cleaning. Brace plugs and bulkheads to prevent release during the low -pressure air test. Locate gauges, air piping manifolds, and valves above the ground. Do not allow anyone to enter a manhole or inlet of a plugged pipe when it is under pressure. Equip the air test ing apparatus with a pressure release device, such as a rupture disk or a pressure relief valve, designed to relieve pressure in the pipe at 6 psi when under test. SECTION 61 GENERAL Start the test after the pressure is stabilized at or above an internal pressure of 3.5 psi greater than the average back pressure of the groundwater that could submerge the pipe. Start recording the time when the internal pressure drops to 3.5 psi. The tested portion of the pipe passes the field leakage test when the pressure drop is less than 1 psi for the time period calculated for the size and length of the pipe to be tested as shown in the following table: Minimum Test Time for Pressure Drop Nominal pipe diameter (in) Time for pressure drop (minutes/100 ft) 6 0.7 8 1.2 10 1.5 12 1.8 15 2.1 18 2.4 21 3.0 24 3.6 27 4.2 30 4.8
61-2.01D(3)(d) Other Allowable Tests
If authorized, you may test :
1.Pipes over 27 inches in nominal diameter 1 joint at a time under ASTM C1103 instead of the exfiltration test specified in section 61 -2.01D(3)(b).
2.Plastic pipe 30 inches or less in nominal diameter with the low -pressure air test specified in ASTM F1417.
3.Pipes 36 inches or less in nominal diameter with the negative 3.5 p si vacuum air pressure test specified in ASTM C1214 instead of the exfiltration test or low -pressure air test specified in section
61-2.01D(3)(b) and 61 -2.01D(3)(c). The minimum test times for pressure drop for pipes:
3.1. 30 inches in nominal diameter and smaller must be the same as the low -pressure air test specified in section 61 -2.01D(3)(c) 3.2. 33 inches in nominal diameter must be 5.4 minutes per 100 feet 3.3. 36 inches in nominal diameter must be 6.0 minutes per 100 feet
61-2.01D(3)(e) Joints or Pi pe Section Not Passing Leakage Testing
Identify joints or pipe sections that exceed the maximum allowable leakage after you complete field leakage testing. Repair and retest the failed joints or pipe sections until they comply with the test requirements. Repair and retest the failed joints or pipe sections as specified in the repair procedures submitted under section 61 -2.01C. If the same joint fails the leakage test a second time, remove and replace the pipe sections on either side of the joint with new pi pes. Replace any pipe section that fails. Retest the replaced pipe section for leaks.
61-2.01D(3)(f) Reserved
61-2.02 Materials
Resilient joint material must be a neoprene expanded rubber or sheet rubber gasket, "O" ring rubber gasket, butyl rubber base joint sealant, or other authorized resilient material. All joints, including any connection, must be capable of transferring the required shear across the joint. Watertightness must be attained by use of an authorized durable, high -quality, resilient joint material designed to perform the intended function.
61-2.03 Construction
Not Used SECTION 61 GENERAL
61-2.04 Payment
The payment quantity for field leakage testing:
1.Is the length of the pipe that has passed field leakage tests
2.Is measured: 2.1. Along the invert of the pipe 2.2. To the inside face of drainage inlets or similar structures that are within the length of the tested pipe
3.Includes the length through elbow s, tees, and other fittings that have passed field leakage tests
61-3 Alternative Culverts
61-3.01 General
Section 61 -3 includes specifications for constructing alternative culverts. Choose from the types of alternative culverts shown. Reinforced concrete pipe must comply with section 65. Corrugated steel pipe and pipe arches must comply with section 66. Corrugated aluminum pipe and pipe arches must comply with section 66. Corrugated polyethylene pipe must comply with section 64. Corruga ted PVC pipe with smooth interior must comply with section 64. Polypropylene dual wall pipe must comply with section 64. Structural steel plate pipe, arches, and pipe arches must comply with section 67. Structural aluminum plate pipe, arches, and pipe arch es must comply with section 67. Reinforced concrete box culverts must comply with section 51. Alternative culverts include concrete collars and concrete tees and reinforcement for connecting new pipe to existing or new facilities.
61-3.02 Materials
Concre te for the collars and tees must be minor concrete. Reinforcement for the concrete collars or tee connections must comply with section 52.
61-3.03 Construction
Not Used
61-3.04 Payment
Not Used
61-4 Alternative Slotted Pipe
61-4.01 General
Section 61 -4 includes specifications for installing alternative slotted pipe . Choose from the types of alternative slotted pipe shown. Do not mix different types of slotted pipe in the same installation. Slotted plastic pipe must comply with section 64 -3. Slotted corrugated steel pipe must comply with the specifications for slotted corrugated steel pipe in section 66 -2.
61-4.02 Materials
Not Used SECTION 61 GENERAL
61-4.03 Construction
Not Used
61-4.04 Payment
Not Used
61-5 Concrete Backfill for Pipe Trenches
61-5.01 General
61-5.01A Summary
Section 61 -5 includes specifications for placing concrete backfill in pipe trenches .
61-5.01B Definitions
Reserved
61-5.01C Submittals
If RSC is used for concrete backfill, submit the concrete mix design and test data from an authorized laboratory at least 10 days before excavating the pipe trench. The laboratory must specify the cure time required for the concrete mix to attain a 500 psi compressive strength when tested under California Test 521.
61-5.01D Quality Assurance
Reserved
61-5.02 Materials
Concrete backfill must comply with the specifications for minor concrete, except the concrete must contain at least 380 pou nds of cementitious material per cubic yard. You may use RSC for concrete backfill except:
1.Section 90 -1 does not apply
2.RSC must comply with minor concrete sections 90 -2.01C, 90 -2.01D, 90 -2.02B, 90 -2.02C 90 -2.02D and 90 -2.02E
61-5.03 Construction
For installation of plastic pipe where saturated clay, peat, or other unsuitable material is encountered immediately adjacent to the pipe trench, the material must be removed to a distance at least equal to 1/4 of the pipe diameter, but not less than 6 inche s, on each side of the pipe. Place concrete backfill in the trench against undisturbed material at the sides and bottom of the trench in a way that prevents (1) floating or shifting of the pipe and (2) voids or segregation of the concrete. Immediately remove foreign material that falls into the trench before or during placement of the concrete. Construct and compact earth plugs at the ends of the planned concrete backfill to contain the concrete within the trench where necessary. Wherever mi nor concrete is used, do not place materials on top of the concrete backfill within 8 hours of placing the concrete backfill. Wherever RSC is used, do not place materials on top of the concrete backfill before the required cure time to attain 500 psi has e lapsed. Consolidate concrete backfill using high -frequency internal vibrators. If HMA is to be placed directly on the concrete backfill, broom the surface with a heavy broom to produce a uniform rough surface.
61-5.04 Payment
The payment quantity for conc rete backfill (pipe trench) is the volume determined from the dimensions shown and the length of pipe if the limits of concrete backfill are shown. If the limits of concrete backfill are not shown, the payment quantity for concrete backfill (pipe trench) i s the volume determined as follows: SECTION 61 GENERAL
1.Horizontal limits are determined from vertical planes 6 inches outside of each side of the pipe for a diameter or span of less than 42 inches and 12 inches outside of each side of the pipe for a diameter or span of 42 inches or greater.
2.Upper limit is determined from a horizontal plane 12 inches above the top of the pipe.
3.Lower limit is determined from a horizontal plane at the bottom of the pipe.
4.If alternative pipe is shown, the payment quantity for concrete backfill (pipe trench) is determined from the required trench width for the alternative pipe with the smallest outside diameter and the length of the pipe.
5.Volume occupied by the pipe is not included in the payment quantity. Concrete backfill placed ou tside of these limits is not included in the payment.
61-6 Temporary Culverts
61-6.01 General
Section 61 -6 includes specifications for constructing temporary culverts . Temporary culverts include pipe bends, wyes, tees, and other branches. Excavation, backfill, and shaped bedding must comply with section 19 -3.
61-6.02 Materials
You may install a removed, undamaged, temporary culvert in the permanent work if it complies with the specifications for the permanent culvert and it is new when installed as a temporary culvert on the project.
61-6.03 Construction
Install a size and type of temporary culvert capable of sustaining the intended load and discharging a quantity of water equivalent to the type and size of culvert shown. Obtain authorization for the strength and capacity of the culvert before its installation. Excavate and backfill the trench for a temporary culvert in a way that provides a firm, nonsettling foundation for the roadbed to be cons tructed over the culvert.
61-6.04 Payment
The payment quantity for temporary culvert:
1.Is the length measured along the centerline of the pipe and parallel with the slope line.
2.Includes the length of pipe reducers, bends, wyes, tees, and other branches to the point of intersection. The length of pipe reducer is included in the length of the larger diameter pipe connected to the reducer.
3.Is the length of pipe necessary to be placed before cutting, measured in 2 -foot increments, if the pipe is cut to fit a structure of slope.
61-7 Temporary Slotted Pipe
Reserved
61-8 61-15 Reserved
Source: California Standard Specifications, 2024 Edition. Pages 951–958 of 1,372.