SECTION 722 MANHOLES, CATCH BASINS, AND INLETS

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SECTION 722

MANHOLES, CATCH BASINS, AND INLETS


722.01
DESCRIPTION

This work consists of constructing and adjusting
manholes, catch basins, and inlets, including the furnishing or
resetting of necessary metal frames, covers or gratings, valve boxes, or other accessories to new lines and
grades.


722.02

EQUIPMENT

Reserved


722.03
MATERIALS

Item

Section

Concrete Class
AE

802

Precast Reinforced Concrete Pipe Manholes

830.01

B or C

Frames, Tops, Covers, Fittings, and Gratings

834.02 C or D

Reinforcing Steel

836.02 A


Compose m
ort
a
r

of o
ne
part
cement

to two parts of sand by
volume
.

A maximum of 10 percent of
the cement
content, by weight, may be replaced with lime.


722.04
CONSTRUCTION REQUIREMENTS

A.

Precast Reinforced Concrete Pipe Manholes, Inlets, and Catch Basins


Use reinforced concrete sewer pipe
for this purpose.
If
this type of construction is used,
construct
the joints
by one of the following methods:

1.

Mortar
;

2.

Rubber Gaskets
; or

3.

Cold applied preformed plastic gaskets.


B
.

Concret
e

Construction

(Cast
-
in
-
Place)


Construct cast in place concrete as specified in
Section 602

“Concrete Structures.”




Finish the concrete surface to present a neat and smooth appearance. Fill honeycomb with cement mortar
mixed in the same proportions used in the concrete for the
work.


C.

Concrete

Base

(Pre
-
Cast

or

Cast
-
in
-
Place)

Shape the invert channel to the true shape of the lower half of the pipe or sewer
.
Construct

the bottom
edge of the barrel for manholes, catch basins, and inlets to fit

flush on

the base. Grout the joint between
the base and the
barrel
with cement mortar.


D
.

Pipe

Connections


Extend pipe or
tile

through the walls
a sufficient distance to allow for connections
.
Construct the
concrete

around the pipe or tile to prevent leakage along their outer surface.
Ensure the inside ends are flush with or
protrude through the inside walls, and the pipe is the same size and kind as those they connect with on the
outside.



E
.

Placing

Casting
s

Set castings in full mortar beds
.


Construct manholes, catch basins, and inlets so that a maximum of
6

inch
es of precast

concrete
adjustment rings are needed to set the casting to grade.


F
.

Backfill

Place
back
fill in lifts not exceeding 6 inches loose measurement. Compact the material as specified in
Section 203.04 E.2.a “AASHTO T 180.”


G.

Cleaning

Clean all
manholes, catch basins, and inlets
of accumulations of silt,
and

deleterious material
.


H
.

Adjustmen
ts

to

Existing

Units


Make adjustments to the structure walls by the use of
brick, solid concrete blocks,
precast ring, or Class AE
concrete so that a seat of proper dimensions may be reconstructed to receive the casting, grating, or cover.
If the top of the existing structure is weak and faulty, replace it as directed, and
complete
the extension.


I.

Maintena
nce of Drainage

If the existing drainage facilities become inoperable before the new drainage system is functioning, provide
sufficient temporary pumping
and

drainage facilities to keep the roadway drained to the satisfaction of the
Engineer. Include the c
ost of providing sufficient temporary pumping and drainage in the price bid for other
items.


722.05 METHOD OF MEASUREMENT


The Engineer will measure
, completed and in place
,

as specified in Section 109.01

“Measurement of
Quantities”

and as follows:


A.

Catch

Basins

and

Inlet


The Engineer will include the base, casting, cover, and gate as part of the catch basin and inlet bid item


B.

Manholes

The Engineer will include the base, casting, cover, and gate as part of the manhole bid item.


C.

Manhole

Risers

The Engineer will measure
manhole risers
from the base to the
bottom of the
precast cover or the casting.


722.06 BASIS OF PAYMENT

Pay

Item

Pay

Unit

Manhole
___ IN

Each

Manhole Tee ___IN × IN

Each

Manhole Sanitary

Each

Manhole Riser
__ IN

Linear Foot

Inlet


Type __

Each

Adjust Manhole

Each

Adjust Inlet

Each

Adjust Utility Appurtenance

Each


Such payment is full compensation for furnishing all materials, equipment, labor, and incidentals to complete
the work as specified.




Changes noted in
Section 722


Manholes, Catch Basins, and Inlets


722.
03

MATERIALS



Removed:

o

“Materials shall meet the following:

o

“Brick”

o

Concrete Masonry Units”

o

“All materials used are subject to approval.”

722.04

CONSTRUCTION REQUIREMENTS



2008 Spec Section A. Excavation
is REMOVED



2008 Spec Section B. Brick Masonry Construction is REMOVED



Section
C. Concrete Base (Pre
-
Cast or Cast
-
in
-
Place)

o

Removed:



“The thickness and other dimensions of the base shall be as specified.”



Section D. Pipe Connections

o

Removed:



“The cost of th
e materials, equipment, and labor to make the connections shall
be included in the other items.”



2008 Spec Section H. Reinforcement is REMOVED



Section E. Placing Castings

o

Removed:



“Castings shall be set accurately to the
correct elevation so no subsequent
adjustment is necessary.”



Section H. Adjustments to Existing Units

o

Note that brick was removed from Materials list; should it not be removed here?



Section I. Maintenance of Drainage

o

How do we include the cost of this drainage maintenance when we don’t know

if it going
to be required?

722.05 METHOD OF MEASUREMENT



Removed:

o

“Excavation, embankment, and disposal of unsuitable or excess materials will not be
measured but will be included in Pay Items.”



Added:

o

“The Engineer will measure, completed and in place, a
s specified in Section 109.01
“Measurement of Quantities” and as follows:”

722.06 BASIS OF PAYMENT



Removed:

o

“Payment will be made at Contract Unit Prices for the following:


o

“Catch Basins”

o

Adjust Catch Basin”



Added:

o

“Manhole Tee ___ IN x IN



Each”

o

“Manhol
e Sanitary”