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LLOYD AND ASSOCIATES
ENGINEERS AND SURVEYORS
REPORTS
DESIGNS
SUPERVISION
APPRAISALS
CONSULTATIONS
June 20, 1980
WATER DISTRIBUTION SYSTEM
ROBERT F. LLOYD
REGISTERED CIVIL ENGINEER 3538
REGISTERED L^ND SuRVEYOR 944
(3 O 5) 5 6 2. 4 1 1 2
1 B 3 S ZOTH STREET
VERO BEACH, FLORIDA
32960
SEBASTIAN HIGHLANDS - UNIT SIXTEEN
This report is the result of review of the Sebastian Highlands,
a portion of Unit 16, Phase One, Water Distribution Plans as submitted
to the City of Sebastian by General Development Corporation as reviewed
by Lloyd and Associates, Consulting Engineers for the City of Sebastian,
Florida.
The water distribution system as proposed by General Develop-
ment Corporation consists of 4" and 6" P. V. C., Class 160, SDR 26, water
mains throughout the subdivision. Supply is from the existing 6" water
main, East of Schumann Waterway on Schumann Drive. A 12" water
main is proposed for the West portion of Schumann Drive from the proposed
tie to the existing 6" water main to a point South of the intersection of
Schumann Drive and Englar Drive and an 8" water main along the northerly
right-of-way of Englar Drive West of Schumann Drive, to a point just
East of the West limits of Unit 16. Fire hydrants are also proposed at
generally 500' radii for the proposed subdivision.
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Without a detailed set of specifications, other than those provided
by graphic illustrations or notes from the plans, the following comments,
recommendations and requests for additional information are necessary:
1. As previously agreed at the June 5th, 1980 workshop,
an electronically detectable plastic tape to be buried
a maximum of 12" below ground surface above all
water mains and services.
2. Where sanitary sewers cross under water mains with
less than 18" vertical clearance, sanitary sewer line
shall be encased in concrete, 10' each side of crossing
or use ductile iron pipe.
3. Points of conflict between storm drainage system,
sanitary sewer system and water distribution system
are not noted on plans.
4. Water main bridge crossing plans should be submitted
to the City Engineer for review and comments.
5. Although fire hydrants have generally been placed
at 500' radii throughout the subdivision, an additional
hydrant should be placed in the vicinity of Lot 9 or 10,
Block 559.
6. We recommend 36" minimum cover on all utilities.
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7. Except in rock, mechanical excavation shall be
limited to 4" above the elevation of the pipe in-
vert. All additional excavation should be made
manually. If storm water drainage or ground water
is encountered, General Development Corporation
shall provide adequate equipment for the removal
of storm or ground waters from the excavated
areas. All pipe shall be laid in a dry trench. A
well point system or other approved dewatering
method shall be utilized to maintain the trench bottom
in a dry condition for pipe laying. Well holes in
road right-of-way shall be grouted immediately
on withdrawal of well points with grout mixed q:l.
8. Concrete encasement detail for sewers crossing
water mains and sewers with cover less than 36"
shall be submitted to the City Engineer for review.
9. Plan indicates thrust blocking figured at 100 psi
water main pressure with 1600 psf soil bearing value.
We recommend areas be computed using 150 psi.
Main pressure resulting from water hammer.
10. Gate valves shall comply with all the applicable
sections of AWWA Standard C500 and be bubble
tight at a 200 psi water working pressure. The
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valves shall have mechanical joint ends for sizes
4" and larger. The valves should be "resilient
wedge" or "resilient seat" gate valves, manufactured
by Clow Corporation or Mueller Company or approved
equal.
11. If butterfly valves are proposed for the 12" water
main, they should be for direct burial with rubber seats
and mechanical joint ends. The valves shall meet the
latest AWWA Standard C504, Class 150B (wafer type
not acceptable) Henry Pratt or equal.
12. A concrete pad shall be poured around the top of the
valve box, 24" x 24" x 4", to prevent damage or move-
ment.
13. If, for any reason, pipe or other structures cannot be
provided with a stable foundation, the unstable materials
shall be removed and replaced with material acceptable
to the Engineer. Muck, peat and other highly organic
soils are considered to be unstable materials and shall
be excavated and hauled off-site as directed by the Fngi-
neer.
14. Pipe manufacturers laying instruction should be submitted
to the City Fngineer.
15. The bedding surface for all pipe should provide a firm
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F
foundation of uniform density throughout the viitire
length of the pipe. The pipe should be carefully
bedded in a soil foundation that has been accurately
shaped and rounded to conform to the lowest one-
fourth of the outside circular portion of the pipe for
its entire length, and shall be tamped to secure
uniform support. The bell holes should be deep
enough to insure that the bell does not bear on the
bottom of the excavation, and should not be excessively
wide in the direction of the pipe.
16. Water lines and mains should be laid and the work
incidental thereto performed in accordance with the
latest AWWA Specifications C600.
17. Trench widths should be held to minimum consistent
with the excavation material encountered.
18. Maximum permissible deflection of PVC pipe shall be
5%, or as recommended by the manufacturer.
19. All backfill in roadbeds is to be compacted to 100
density to finished grade. Density tests shall be taken
at 12" depths to secure adequate density determination.
Owner, at his expense, will make the first density tests -
subsequent retests shall be paid for by the Contractor,
if the first test fails.
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20. Selected backfill should be deposited in trench
uniformly on both sides of the pipe for the full
width of the trench and to the crown of the pipe
for the full length of the pipe prior to pressure
and leakage tests. This backfill material should be
hand tamped in four (4) inch layers and should be
sufficiently tamped with curved tamps to permit
thorough compaction under and on each side of the
pipe to provide support free from voids. Additional
backfill should be free from rocks and stones to 12"
above the top of 8" and smaller pipe and 24" over
larger pipe. The pipe joints should remain exposed
until completion of pressure and leakage tests unless
otherwise authorized by the Engineer.
21. On completion of pressure and leakage tests, the
exposed couplings should be backfilled with selected
material to a depth of 12" over the top of the pipe
and couplings. The backfill, as above the pipe, should
be free from rocks, brush or any perishable or objection-
able matter that would prevent proper consolidation
or that might cause subsequent settlement. It should
be compacted thoroughly by puddling with water or by
tamping if the material does not consolidate readily.
When wetting, it is important that proper precautions
be taken to prevent floating of the pipe when flooding
the trench. Balance of backfill to be placed in lifts.
22. Meter box detail should be submitted to the City Engineer
for review, also indicating proposed positions of installation.
23. Fire hydrants should be traffic model, compression
type, to open left, with 5q" valve opening and one (1)
42„ pumper nozzle and two (2) 22" hoze nozzles, all
with National Standard threads. Hydrants should have
6" inlet connection and National Standard pentagon
operating nut. Hydrants should be Dresser "500" traffic
model manufactured by M & H Valve and Fitting Company
or Centurion A423 manufactured by Mueller Company or
approved equal. Hydrants should meet or exceed the
requirements of the latest AWWA Standard C504. Color
should be 944 Federal Safety yellow as manufactured by
Rust-oleum or equal.
24. Fire hydrant branch line shall use mechanical joint
anchoring fittings including main tee. Set valve at main.
Use of concrete on hydrants is not recommended, because
maintenance and repair require shut-off of consumers
service.
25. All fittings and pipe for service line should be non-
corrosive.
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26. Recommended pressure test procedures:
A. System should be flushed before pressure test with a full
pipe diameter opening. All air and dirt must be removed.
1. Minimum velocity for flushing should be 2. 5 f, p. s. .
2. Install a corporation stop on any high spot in pipe to
release air.
3. Notify Engineer for permission to flush. A minimum
of 24 hrs. prior notice is required. Only when ample
water is available, time will be designated for flushing.
B. Contractor should furnish pump and equipment capable of
maintaining average pressure of 150 psi. 1/4" valve will
be installed in the piping to accept a pressure gauge.
1. Contractor should notify, Engineer a minimum of 24
hours before final pressure and leakage test is to be
made.
2. The Contractor should perform a preliminary pressure
test to determine tightness of pipe and fittings prior to
the final pressure and leakage tests.
3. Pressure should be maintained at 150 psi for four (4)
hours.
4. Total water necessary to maintain pressure must not
exceed AWWA C600 Specifications (chart attached).
5. Facilities should be provided by the Contractor to mea-
sure accurately the amount of water used.
6. The leakage allowance should be based upon the nominal
length of pipe. No allowance for other fitting should be
included.
C. It is the responsibility of the Contractor to make any repairs
necessary to complete this test in a manner satisfactory to the
Engineer.
D. Pressure test must be satisfactorily completed prior to disin-
fection of piping.
Total Leakage Allowed
at 150 psi 4 hour test/1000' pipe, 18' sections
PIPE SIZE 18' LENGTH
20' LENGTH
2
0.76
0. 68
3
1. 12
1.01
4
1.48
1.33
6
2.20
1. 98
8
2.96
2.66
10
3.68
3. 3t
12
4.40
3. 96
14
5. 16
4.64
16
5.88
5. 29
18
6.64
5. 98
20
7.36
6.62
24
8.84
7.96
Other lengths of pipe or additional fittings for a 4 hr. test can be figured
with the following formula: L = ND—VII-P--
7400
L - Leakage Allowable, N - Number of Joints, D - Nominal Pipe Dia.,
P - P. S. I. Average.
27. Recommended sterilization procedureH of completed pipeline:
The Contractor should sterilize all distribution and service mains
as follows:
It is the Contractor's responsibility to install an adequate sample
point at the end of the line, i. e. a stand pipe with a hose bibb, fire
hydrants must not be used as a sample point. Also, a 3/4" valve must
be installed next to inlet gate valve on main, and chlorine must be
pumped through entire section of main being tested. Chlorine and
water must be added at the same time, for uniform mixing.
The proper chlorine dose for a minimum of 50 ppm chlorine residual,
after 24 hours of retention time should be at least 200 ppin. To
determine dosage enter the water main diameter and length on attached
chart to obtain weight of H. T. H. (calcium hypochlorite) or other
approved chlorine containing chemical (as adjusted) and mix in 50
gallon drums. Not more than 5 pounds of chemical shall be dissolved
in each 50 gallons of water. The chlorine solution must be retained
in the main for 24 hours.
After the 24 hours, sample will be checked by the City Engineer
or his designated representative, to determine that there is a
minimum of 50 ppm chlorine residual. Contractor will then flush
the main until normal system chlorine residual is observed at the
discharge end of the pipe. Bacteriological samples will be taken on
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QT7V TTTATIT
2"
41?
611
8"
10"
12"
14"
16"
18"
2 0"
two (2) consecutive days. Sterilization will be repeated by and at
Contractor'H expense if two (2) successive bacteriological samples
do not test negative.
Total Pounds of 70% Calcium Hypochlorite
*H. T. H. ) Needed to Dose at 200 PPM
LENGTH OF PIPE IN FEET
100' 200' 300' 400' 500' 600' 700' 800' 900'
.04
.08
. 12
. 16
.20
.23
.27
.31
. 35
.16
.31
.47
.62
.78
.94
1.1
1.3
1.4
.35
.71
1.1
t.4
1.8
2.1
2.5
2.8
3.1
.64
1.3
1.9
2.5
3.1
3.7
4.3
5.0
5.6
.98
2.0
2.9
3.9
4.8
5.8
6.8
7.7
8.7
1.4
2.8
4.2
5.6
7.0
8.4
9.8
11.2
12.5
1.9
3.8
5.7
7.6
9.5
11.4
13.3
15. 2
17.1
2.5
5.0
7.4
9.9
12.4
14.9
17.3
19.8
22. 3
3.1
6.3
9.4
12. 5
15. 7
18.8
21.9
25.1
28. 2
3.9
7.7
11.6
15.5
19.3
23.2
27.1
30.9
34.8
1000'
.38
1. 6
3.5
6.2
9. 7
13.9
19.0
24. 7
31.3
38. 7
* (Adjust other approved chloring compoinds on basis of available chlorine)
SIZE
GALLONS OF WATER PER EACH FOOT
VOLUME IN GALLONS
2"
. 16
4"
.65
61?
1. 47
8"
2. 61
10"
4.08
12"
5.88
14"
8.00
16"
10.44
18"
13. 22
20"
16.32
=am
28. Surplus pipeline material, excess backfill, temporary structurcy
and all debris shall be removed by the contractor, and the con-
struction site left clean to the satisfaction of the Cite Engineer.
29. The Engineer or his designated representative should perform
ongoing inspection during the construction of this system to ensure
compliance with sound engineering practices. Work should be
stopped on any individual portion or the entire project if in the
opinion of the City Engineer the construction is not in the best
interests of the City of Sebastian or the future residents of the
proposed subdivision.
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