HomeMy WebLinkAboutCDP 96-10; North Batiquitos Sewage Force Main; Coastal Development Permit (CDP) (11)DANIEL BO\i.L ENGINEERING,
Civil Engineering Services
CARLSBAD MUNICIPAL WATER DISTRICT
5950 El Camino Real
Carlsbad, CA 92008
Attention: Mr. William E. Plummer, P.E.
District Engineer
Carlsbad Municipal Water District
North Batiquitos Sewage Force Main Replacement Project
CMWD Project No. 85-401
September 12, 1996
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1
H ® LULL—" " ' !
SEP 1 51996
In accordance with Task 1 of our Proposal dated July 24, 1996, attached is our
letter report including our analysis, preliminary opinion of probable costs, and
recommendations for the North Batiquitos Sewer Force Main Replacement Project.
We have included the pertinent comments from our meeting with you on
August 29,1996, and our subsequent telephone conversations related to Alternate
3A.
We are prepared to proceed with the final design and preparation of plans and
specifications upon your authorization and a contract amendment to include
replacement of the 8-inch water line at the top of the slope. The request for
contract amendment will be sent to you under separate cover.
If you have any questions regarding the above, please do not hesitate to call.
DANIEL BOYLE ENGINEERING, INC.
Daniel B. Boyle, P.E.
Managing Engineer
DBB:DGS:kmh
End.
C15-102-00
LTR09-96.RPT
Daniel G. Smith, P.E.
Associate Engineer
3142 Vista Way. Suite 201 Oeeanside, CA 92056 (619) 433-8710 FAX (619) 433-9709
CARLSBAD MUNICIPAL WATER DISTRICT
NORTH BATIQUITOS FORCE MAIN REPLACEMENT PROJECT
Project No. 85-401
SECTION
TABLE OF CONTENTS
PAGE
1.0 INTRODUCTION
2.0 ALTERNATE ALIGNMENTS
3.0 ENVIRONMENTAL CONCERNS
4.0 PRELIMINARY OPINION OF PROBABLE COST
5.0 RECOMMENDATIONS AND CONCLUSIONS
INCLUDED AFTER SECTION 5.0
Exhibit No. 1
Exhibit No. 2
Exhibit No. 3
Exhibit No. 4
Exhibit No. 5
Exhibit No. 6
Exhibit No. 7
Exhibit No. 8
Alternative Route No. 1
Alternative Route No. 2
Alternative Route No. 3
Alternative Route No. 4
Section A-A
Section B-B
Section C-C
Section D-D
Table No. 1 Preliminary Opinion of Probable Construction Costs
Table No. 2 Summary of Opinion of Probable Construction Costs
C15-102-00
1.0 INTRODUCTION
In accordance with the Scope of Work presented in our proposal dated July 24, 1996,
Daniel Boyle Engineering, Inc. has completed Tasks Nos. 1.1 through 1.3, which are as
follows:
SCOPE OF WORK
TASK NO. 1: DESIGN LETTER REPORT
1.1 Refinement of our preliminary design analysis for the three alternative
force main routes, pipe alternatives, update cost estimates and prepare
a list of pros and cons for each alternative.
1.2 Meet with District staff to discuss in detail our analysis and request that
the District make a selection of the preferred alternative.
1.3 After the District selects the preferred alternative, summarize the results
of our study in a Design Letter Report which will contain our conclusions
and recommendations, submit the report to the District for approval, and
request a Notice To Proceed with the final design and preparation of
plans and specifications.
This report represents the conclusions of our analysis of the alternative force main routes
and our meeting with District staff to make a selection of the preferred alternative.
2.0 ALTERNATIVE ALIGNMENTS
Four basic alternative alignments for the force main routing were identified and analyzed.
The alternative alignments are shown on Exhibit Nos. 1, 2, 3, and 4, which are contained
herein.
2.1 Alternative Route No. 1, refer to Exhibit No. 1, is an alignment that roughly
parallels the existing force main alignment. The sections A, B, and C as shown
on Exhibit Nos. 5, 6, and 7 show the existing and proposed utilities within
Gabbiano Lane.
The advantages and disadvantages of Alternative Route No. 1 are shown below:
Advantages for Alternate No. 1
• Would allow short-term "fix" to avoid conflict with storm drain construction
for Tract 89-19 within Gabbiano Lane.
• Parallel route to existing force main will allow use of clearances designed in
proposed tract utilities.
• No additional easements required.
• Allows for passage under existing 72-inch storm drain without dip section.
C15-102-00 1
CMWD - North Batiqurtos Force Main Replacement Project September 1996
Disadvantages for Alternate No. 1
• Long, deep sections with greater than 7-foot of cover.
• Force main still within backyard/sideyard easements.
• Close proximity of existing force main in 100-foot section north of Piovana
Court.
2.2 Alternative Route No. 2 which is shown on Exhibit No. 2 also roughly parallels the
existing force main alignment until it intersects with Piovana Court. From that
point, the alignment turns westerly and into the cul-de-sac on Piovana Court west
of Gabbiano Lane. There are two variations, Alternate 2A and 2B, which depict
two different force main alignments from the cul-de-sac to the point of connection
with the existing manhole.
The advantages and disadvantages of Alternate No. 2A and 2B are described as
follows:
Advantages for Alternate No. 2A
• Eliminate force main in backyard easements.
• Parallel route to existing force main in Gabbiano Lane will allow use of
clearances designed in proposed tract utilities.
• No additional easements required.
• Shortest alternate route in roadways.
Disadvantages for Alternate No. 2A
• Dip section required to pass beneath existing 72" storm drain.
• Deep sections, greater than 7-foot of cover, in Gabbiano Lane.
• Potential future maintenance difficulties in sideyard easement.
• Realign proposed water line in sideyard easement.
• Would not provide short-term "fix" for storm drain within Tract 89-19.
C15-102-00
CMWD - North Batiquitos Force Main Replacement Project September 1996
Advantages for Alternate 2B
• Eliminates backyard and side yard easements to reduce future negative
maintenance accessibility situations.
• Parallel route to existing force main in Gabbiano Lane will allow use of
clearances designed in proposed tract utilities.
Disadvantages for Alternate 2B
• Longest alternative route.
• Requires additional easement along westerly boundary of Tract 89-19.
• Dip section required to pass beneath existing 72-inch storm drain.
• Deep sections (greater than 7-foot cover) in Gabbiano Lane.
• Require additional environmental clearance.
• Would not provide short-term "fix" for conflict with storm drain within Tract
89-19.
2.3 Alternative Route No. 3 shown on Exhibit No. 3 parallels the existing force main
along the access road to the pump station, south and east of Gabbiano Lane.
From that point it generally follows the westward extension of the access road to
the westerly right-of-way of the access road. It then proceeds northwesterly in
a long, sweeping arc, concave northeasterly to a point on the southerly right-of-
way of Piovana Court. There are two variations of alignments to the point-of-
connection from this point, similar in configuration to Alternate 2A and 2B, labeled
Alternate 3A and 3B. The advantages and disadvantages of Alternate 3A and 3B
are listed below:
Advantages for Alternate 3A
• Shortest alternate route.
• No additional easements required.
• No dip sections would be required.
C15-102-00
CMWD - North Batiquitos Force Main Replacement Project September 1996
Disadvantages for Alternate 3A
• Depth of excavation through hillock containing the eucalyptus stand will be
16-18 feet deep to avoid high point in line.
• Several existing eucalyptus trees would probably be lost due to excavation
width.
• Potential future maintenance difficulties in sideyard easement.
• Realign proposed water line in sideyard easement.
• Would not provide short-term "fix" for conflict with storm drain within Tract
89-19.
Advantages for Alternate 3B
• Eliminates backyard and side yard easements to reduce future negative
maintenance accessibility situations.
• Out of roadway alignment.
• No dip sections would be required.
Disadvantages for Alternate 3B
• Longest off-road alignment.
• Depth of excavation through hillock containing the eucalyptus stand will be
16-18 feet deep to avoid high point in line.
• Several existing eucalyptus trees would probably be lost due to excavation
width.
• Additional easements would be required on south side of Piovana Court
cul-de-sac and along westerly boundary of Tract 89-19.
• Would not provide short-term "fix" for conflict with storm drain within Tract
89-19.
2.4 Alternative Route No. 4 which is shown on Exhibit No. 4 was briefly reviewed and
determined not to be feasible due to lack of capacity in existing gravity mains.
No advantages or disadvantages will be discussed for this alternate.
C15-102-00
CMWD - North Batiquitos Force Main Replacement Project September 1996
3.0 ENVIRONMENTAL CONCERNS
As part of Task 1.2, the various alignment alternatives were discussed with the CMWD
staff on August 29,1996. That meeting was also attended by Mr. Jerry Scheid of RECON,
the District's environmental consultant. Mr. Scheid stated that the environmental concerns
the District may face with each alternate, with the exception of those alternates traversing
previously undisturbed areas of the steep slopes west of Piovana Court, would not be of
major concern to the Resource Agencies, and any mitigation measures would be minimal.
The areas of undisturbed steep slopes contain costal sage and are habitat to the
gnatcatcher. Construction in these areas would be of concern to the Resource Agencies.
4.0 PRELIMINARY OPINION OF PROBABLE CONSTRUCTION COST
Based upon our analysis, we have prepared a Preliminary Opinion of Probable
Construction Cost for each viable alternative alignment. Table No. 1, attached herewith,
provides a breakdown of those costs. Table No. 2 summarizes the costs of the various
alternatives. The Probable Construction Costs assume ductile iron pipe as the piping
material. An overall deduct for using C-900 PVC Pipe is shown on Table No. 2. Final
construction cost estimates will be prepared for the selected alternative after completion
of the construction plans and specifications.
5.0 RECOMMENDATION AND CONCLUSIONS
Upon the review of the analysis of alternative alignments, the District selected Alternate
3A as the preferred alignment. The final location of that alignment will be refined in the
final design process with emphasis on minimizing the number of fittings required. RECON
has stated the impacts of this alignment would not be of major concern to the Resource
Agencies, and the final design process will also be sensitive to minimizing the
environmental impacts.
The District must acquire an easement from the Tract 89-19 property owner for
construction as well as for operation and maintenance of the proposed sewage force
main.
We recommend the CMWD authorize Daniel Boyle Engineering, Inc., to proceed with final
design of the North Batiquitos Force Main Replacement Project and preparation of
Construction Plans and Specifications as described in Task 2 of our Proposal dated July
24, 1996. The pipeline will be designed using C-900 PVC pipe which is our
recommendation for the piping material.
C15-102-00
CMWD - North Batiquitos Force Main Replacement Project September 1996
Ductile iron fittings will be used with the PVC pipe and will be protected from corrosion
on the outside by an exterior polythane coating and a DIPRA-approved polyethylene
encasement wrapped by 10 mil PVC tape along the entire length of the polyethylene
encasement. In addition, each fitting shall be completely encased in concrete. The
ductile iron fittings will be polythane lined to protect from interior corrosion.
C15-102-00
NORTH BATIQUTTOS SEWAGE FORCE MAIN
SECTION A-A
R/W 60'R/W
20'20'
TO DISCHARGE
MANHOLE
GABBIANO LANE NORTH
OF PIOVANA COURT
SCALES
HORIZONTAL! tMO*
VERTICALi 1"»10'
EXHIBIT No. 5
CARLSBAD MUNICIPAL WATER DISTRICT DANIEL BOYLB ENGINEERING, INC.
SEPTEMBER 1996
NORTH BATIQUTTOS SEWAGE FORCE MAIN
SECTION B-B
R/W 60'R/W
20*20'
GABBIANO LANE SOUTH
OF PIOVANA COURT
SCALES
HORIZONTAL: T.10'
VERTICALi 1"i10'
EXHIBIT No. 6
CARLSBAD MUNICIPAL WATER DISTRICT DANIEL BOYLE ENGINEERING. INC.
SEPTEMBER 1996
NORTH BATIQUTTOS SEWAGE FORCE MAIN
SECTION C-C
R/W R/W
GABBIANO LANE SOUTH
OF CIGNO COURT
SCALES
HORIZONTAL 1"«10'
VERTICAL. 1".10'
EXHIBIT No. 7
CARLSBAD MUNICIPAL WATER DISTRICT DANIEL BOYLE ENGINEERING. INC.
SEPTEMBER 1996
NORTH BATIQUTTOS SEWAGE FORCE MAIN
SECTION D-D
R/W R/W
T°D'SCHARQE
MANHOLE
ALTERNATIVE
ROUTE NO. 2
GABBIANO LANE SOUTH
OF PIOVANA COURT
SCALES
HORIZONTAL: 1"«10'
VERTICALi 1".10'
EXHIBIT No. 8
CARLSBAD MUNICIPAL WATER DISTRICT DANIEL BOYLB ENOINBBRINO. INC.
SEPTEMBER 1996
TABLE NO. 1
CARLSBAD MUNICIPAL WATER DISTRICT
NORTH BATIQUITOS FORCE MAIN REPLACEMENT PROJECT
PRELIMINARY OPINION OF PROBABLE CONSTRUCTION COSTS
A.
Item No.
1.
2.
3.
4.
5.
6.
7.
ALTERNATE NO. 1
Quantity Description Unit
1820 LF
L.S.
6EA
3EA
L.S.
SEA
LS.
14-inch diameter polythane lined,
polyethylene encased ductile iron pipe $
Metering structure
Slope anchors
Inspection manholes
Special construction at utility crossings
Corrosion protection test stations
Special construction methods for steep
slope construction
Cost
67
LS.
1,000
1,000
LS.
1,400
LS.
Subtotal
B.
Item No.
1.
2.
3.
4.
5.
6.
7.
Total Opinion
Construction Contingencies (g
of Probable Construction Cost for Alternate Route
ALTERNATE NO. 2A
Quantity Description Unit
1800 LF
LS.
6EA
SEA
LS.
SEA
LS.
14-inch diameter polythane lined,
polyethylene encased ductile iron pipe $
Metering structure
Slope anchors
Inspection manholes
Special construction at utility crossings
Corrosion protection test stations
Special construction methods for steep
slope construction
)20%
No. 1
Cost
64
LS.
1,000
1,000
LS.
1,400
LS.
Amount
Subtotal
Construction Contingencies @ 20%
Total Opinion of Probable Construction Cost for Alternate Route No. 2A
$
$
$
$
121,940
42,000
6,000
3,000
5,000
5,200
30.000
213,140
42.660
255,800
Amount
115,200
42,000
6,000
3,000
4,500
5,200
30.000
206,900
41.100
248.000
C15-102-00
TABLE NO. 1 (continued)
c.
Item No.
1.
2.
3.
4.
5.
6.
7.
ALTERNATE
Quantity
2070 LF
LS.
6EA
4EA
LS.
SEA
LS.
NO. 2B
Description
14-inch diameter polythane lined,
polyethylene encased ductile iron pipe
Metering structure
Slope anchors
Inspection manholes
Special construction at utility crossings
Corrosion protection test stations
Special construction methods for steep
slope construction
Unit Cost
$ 64
LS.
1,000
1,000
LS.
1,400
LS.
Subtotal
Construction Contingencies @ 20%
D.
Item No.
1.
2.
3.
4.
5.
6.
7.
Total Opinion
ALTERNATE
Quantity
1770
LS.
6EA
4EA
LS.
3EA
LS.
of Probable Construction Cost for Alternate
NO. 3A
Description
14-inch diameter polythane lined,
polyethylene encased ductile iron pipe
Metering structure
Slope anchors
Inspection manholes
Special construction at utility crossings
Corrosion protection test stations
Special construction methods for steep
slope construction
Route No. 2B
Unit Cost
$ 63
LS.
1,000
1,000
LS.
1,400
LS.
Amount
132,480
42,000
6,000
4,000
3,000
5,200
26.000
218,680
43.720
262.400
Amount
Construction Contingencies @ 20%
Total Opinion of Probable Construction Cost for Alternate Route No. 3A
63 $
LS.
1,000
1,000
LS.
1,400
LS.
btotal $
>20%
lo. 3A
111,510
42,000
6,000
4,000
2,000
5,200
30.000
200,710
40.140
240.850
C15-102-00
TABLE NO. 1 (continued)
E. ALTERNATE 3B
Item No. Quantity Description
1.
2.
3.
4.
5.
6.
7.
1980 LF
LS.
6EA
4EA
LS.
3EA
LS.
14-inch diameter pdythane lined,
polyethylene encased ductile iron pipe
Metering structure
Slope anchors
Inspection manholes
Special construction at utility crossings
Corrosion protection test stations
Special construction methods for steep
slope construction
Unit Cost Amount
63 $
LS.
1,000
1,000
LS.
1,400
124,740
42,000
6,000
4,000
1,000
5,200
LS.
Subtotal
Construction Contingencies @ 20%
Total Opinion of Probable Construction Cost for Alternate Route No. 3B
26.000
208,940
41.760
250.700
C15-102-00
TABLE NO. 2
CARLSBAD MUNICIPAL WATER DISTRICT
NORTH BATIQUITOS FORCE MAIN REPLACEMENT PROJECT
SUMMARY OF OPINION OF PROBABLE CONSTRUCTION COSTS
ALTERNATE PROJECTED
ROUTE CONSTRUCTION COST
No. 1 $ 255,000
No. 2A 248,000
No. 2B 262,400m
No. 3A 240.850'21
No. 3B 250.700'1'21
No. 4 N/A(3>
111 Does not include cost of preparation of easement documents or acquisition of
easement.
121 Does not include replacement of eucalyptus trees.
131 This alternative is not feasible.
C-900 PVC PIPE CLASS 200 MATERIAL ALTERNATE
By utilizing C-900 PVC pipe in the construction of the North Batiquitos Sewage Force
Main, the project construction cost could be reduced for each alternate route by
approximately $21,000.
C15-102-00