1.Aba Moga to Gera Road
Item Station
No. /Description
A.2 0+541
A3.
@0+541 &
0+720
Section
Structure
(Box
culvert)
Comment
✓ Double box culvert
dimension to reduce
fill height.
✓ Use the standard
box culvert
dimension
✓ The same it’s
mentioned as pipe
culvert in the PP
Drawings please
edit it.
✓ It is indicated as 4.5
m span by 2.5 m
clear height in the
hydraulic analysis
but it is mentioned
4 by 2.5 m in
structure, please
check and correct.
✓ The gradient at the
culvert approach
should be adjusted
as per the standard.
Response
✓ The use of a double cell box
culvert does not reduce the
fill height; rather, it increases
it. Because we are increasing
the width while maintaining
the discharge, we are
implicitly reducing the wall
height if we use a double cell
box culvert. Furthermore, if
we choose the double-cell
one, we will incur extra costs
that are unnecessary.
✓ The standard culvert
dimensions can be used if and
only if the proposed culvert
dimensions match the
opening sizes in the standard
drawings. As far as structural
design is concerned, any
culvert size that is safe and
economical can be designed
and used according to the
LRFD provisions.
✓ The comment regarding pipe
culvert mentioned above is
not clear.
✓ Comment accepted; it is a
mistake in the drawing. But it
is designed for a 4.5*2.5 box
culvert. It will be corrected in
the final set of drawings.
✓ The standard (ERA BDM)
provides only a minimum
requirement for longitudinal
slope of 0.5% in order to
prevent silt accumulation
within the culvert. We
provide a longitudinal slope
of 1.5% according to the site
conditions. But if the side
condition assumed during
design differs from what we
have done during design, it
can be modified during
supervision.
Drainage
✓ It is mentioned that
CD structures is
required @1+360,
but not shown in
the culvert design.
Please provide CD
structure @1+380
lowest point)
✓ Accordingly
include the
quantity.
A.4
@1+380,
not@1+360
B.2
32.03
✓ The quantity of
class -A pipe has
not been computed.
Please mention the
correct dimensions
and quantify it.
Please also avoid
other types which
are not necessary
B.3
32.14
B.4
32.06&32.09
✓ The quantity of
manhole is not
correct please
correct it.
✓ The quantity of box
culvert is indicated
in the drainage
works, please
consider them
under dev.8000structures.
✓ The proposed culvert at
station 1+360 will not have
an inlet-outlet detail; it will
be connected by manhole.
There is no need to show its
drawing. It can be considered
as a longitudinal pipe. Since
it is expected that the culverts
will be constructed in
conjunction with the
hydraulic report.
✓ Even though it does not have
a drawing, the quantity is
included.
✓ The pipe culverts are
quantified accordingly.
Bedding type -A is not going
to be used, therefore there is
no need of quantifying it.
And it is not necessary to
remove the other culvert sizes
since there is a possibility of
using other culvert sizes
during construction, and it
will not make confusion since
it is going to be constructed
in conjunction with the
hydraulic reports. It is
expected that the backfill
height of 60 cm above the
pipe culvert is expected to be
filled with excavated material
since it is non load bearing
material.
✓ Comment accepted and it will
be corrected in the final
submission of set of
drawings.
✓ Box culverts are one of the
typical types of minor
drainage structures. As a
result, according to the ERA
Manual, the quantity of minor
drainage must be included in
div.3000. we have included it
under Series 3000.
2. Road Name: Kota Ber to Bosoko
Item Station
No. /Description
B.1 32.02a(iii)
&32.03b(ii)
B.3
Section
Comment
✓ The quantity of
class -A pipe has
not been computed.
Please mention the
correct dimensions
and quantify it.
Please also avoid
other types which
are not necessary
✓ The quantity of side
drainage pipe,
please compute.
✓ The quantity of
manhole is not done
please compute.
32.14
Response
✓ As mentioned above we will
not have a culvert bedded on
class A type bedding and no
need of quantifying it.
✓ The quantity is done based on
the lengths given on the
hydraulic report which is 740
m on each side but we have
tried to account quantities
where there is need on
channelizing the flow.
✓ Comment accepted and it will
be corrected in the final
submission of set of
drawings.
3. Road Name: Haji Munir House to Agricultural Rural Development Office
Item Station
No. /Description
A.1 CD @0+350
B.2
32.09
Section
Drainage
Comment
✓ It is recommended
on PP and drainage
as slab culvert, but
on the structural
design as box
culvert, please edit
it.
✓ The clear span is
not mentioned in
the structural
design.
✓ The wall height is
indicated 2.5 m in
the longitudinal
drawings but it is
designed with 3.0m,
please make
compatible with
3.0m
✓ The quantity of box
culvert is indicated
in the drainage
works, please
Response
✓ The type of drainage structure
decided by the structural
engineer depending on the
site condition. The only thing
which can be given in the
hydraulic analysis is culvert
size and choice between Slab
culvert and box culvert.
Therefore, the structural
drawings shall be followed.
✓ The culvert span is already
shown on the longitudinal
cross-section. During
construction, the rebar detail,
longitudinal cross-section,
and hydraulic report will all
be read altogether.
✓ Comment accepted, and will
be corrected on the final
submission of set of
drawings.
✓ Box culverts are one of the
typical types of minor
drainage structures. As a
result, according to the ERA
consider them
under dev.8000structures.
B.3
32.14
✓ The quantity of
manhole is not done
please compute.
Manual, the quantity of minor
drainage must be included in
div.3000. we have included it
under Series 3000.
✓ Comment accepted and it will
be corrected it the final
submission of set of
drawings.