USA > Massachusetts > Norfolk County > Weymouth > Town annual report of Weymouth 1922 > Part 3
Note: The text from this book was generated using artificial intelligence so there may be some errors. The full pages can be found on Archive.org (link on the Part 1 page).
Part 1 | Part 2 | Part 3 | Part 4 | Part 5 | Part 6 | Part 7 | Part 8 | Part 9 | Part 10 | Part 11 | Part 12 | Part 13 | Part 14 | Part 15 | Part 16 | Part 17 | Part 18 | Part 19 | Part 20 | Part 21 | Part 22 | Part 23
Table 3
Comparison of Pumping Costs
Annual Charges
Plan No.
Description of Plant
Interest and Bonds
Total
*Operation
1st Year
Average
1st Year
Average
1
2-2 Million gal. Cross-compound Steam Pumps Coal at $9.50 per Ton Engineer and Fireman
$7,169
$5,012
$3,759
$12,181
$10,928
2
2-2 Million gal. Turbine-driven Centrifugal Pumps Coal at $9.50 per Ton Engineer and Fireman
7,586
3,612
2,800
11,198
10,386
3
2-2 Million gal. Motor-driven Centrifugal Pumps One Attendant only
7,948
1,526
1,199
9,474
9,147
.
*Based on 250 m.g. per year
31
IMPROVEMENTS NECESSARY TO PROVIDE PROPER FLOW AND PRESSURE WITH LOCAL SYSTEM
If the town is to continue furnishing water from local sources there are several expenditures of considerable magnitude which must be made within the next few years. These expenditures are those on the pumping and distribution system which would not be required if water was taken from the Metropolitan, and they enter directly into the comparison between the cost of developing and maintaining the local supply and that of entering the Metropolitan.
(a) Pumping plant.
Present pumps have been in use for thirty five years and are at the present past rendering proper service. The most that can be expected of them is to act as a standby in the case of emergency, and to put them in condition to do this even would require an out- lay of several thousand dollars.
Knowing the general condition of these pumps, I am not in favor of making any large expenditures upon them, believing it better to apply the cost of repairs to the purchase of new equip- ment.
The water department, in order to prevent an interruption in service, was forced to buy during the past year, two motor driven units which will take care of the pumping requirements tempor- arily.
While the cost of electric current per million gallons is con- siderably greater than the corresponding cost of coal, this differ- ence is largely offset by the comparatively low cost of the electri- cally driven units and the resulting low annual charges for interest and depreciation.
Table 3 gives a comparison of annual expense of pumping under conditions prevailing at present time at South Weymouth pumping station, for two representative steam units and the electrical unit now in operation.
So far as the cost of pumping alone is concerned, there ap- pears to be a considerable margin in favor of electric power. There are however some necessary improvements which must be con- sidered in conjunction with the question of pumping equipment, and which may have a deciding influence on the choice of power.
The present arrangement of electric units would give satis- factory service for a number of years, were it not for the fact that the mains from the pond to the station are not large enough to supply two pumps, in addition to the normal flow on the gravity system.
In fact in times of maximum requirements it is not possible to run one pump without seriously effecting the gravity service. This suction main is moreover the only link between the pond and the distribution system and in case of any accident to it, the town would be without fire protection, and would within a few hours be without water for domestic service.
This condition can be overcome by duplicating the suction main, or by building a new pumping plant on shores of the pond, and laying a force main from that point to Hollis Street.
The latter method has many physical advantages if it can be accomplished without great additional cost, and it is therefore necessary to analyze the costs of both methods before arriving at a
32
final decision on pumping plant.
If electric power is to be relied upon entirely, it is essential that at least 500,000 gallons additional storage be provided at a sufficient height to give reasonable fire protection in case of temporary failure of power.
Under any plan for pumping, this additional storage is badly needed, since under existing conditions, while the present stand- pipe has a nominal capacity of about 700,000 gallons, not over one third of that amount is at sufficient height to be effective for fire protection, and the lower third is too low to be of much value for domestic purposes. Moreover, this tank is about 36 years old, and while apparently in good condition, there is always a possibility of its being thrown out of commission for extensive repairs.
A 500,000 gallon elevated tank located on the highest point between the present pumping station and Great Pond, would have the following advantages:
1. Would furnish ample fire service for 99 per cent of the fires occuring in Weymouth without starting the pumps. (Safe guard against failure of electric power).
2. Reasonable fire and domestic service for nearly 24 hours after complete failure of pumping plant, suction line or intake.
3. Would permit the cleaning and painting of either tank without any interruption of service, and without resort to direct pumping.
4. Reserve against possible failure of old tank.
The need of this storage is so obvious that I have included the cost of a new tank in all of the different plans for reconstructing the pumping end of the system.
It is evident then that there are several possible plans for de- veloping this part of the system, each equally good from the stand- point of service, and each involving a different combination of location, type of pump, storage and supply line.
To determine the relative economy of these various combina- tions, I have made a cost analysis of six different plans, the de- tails of which are as follows:
PLAN ONE
Cross Compound Crank and Fly Wheel Pumps in Present Station
This plan provides for two 2,000,000 gallon cross compound steam pumps, new 20" suction main from pond and new storage tank connected with station by 12 in. force main. This seems to be the most economical type of reciprocating pump for the work, since the required amount of pumping, the extra cost of high duty pumps, more than offsets the coal saving due to increased efficiency.
Initial Investment
2-2,000,000 gallon Cross-compound, Crank and Fly Wheel Units. complete on foundations
$35,370
2-150 H. P. H. T. Boilers 6,000.
Setting Boilers 2,500.
Renewal of Steam Main and Minor Connections 700.
Feed Pumps, Heaters, etc. 1,000
33
New Suction Main and Connections
30,000
Storage Tank, including Land and Connections. 36,350.
111,920.
10 per cent. for Engineering and Supervision
11,192.
Total Investment 123,112.
PLAN TWO
Turbine-driven Centrifugal Pumps in Present Station
Same as plan 1 except that turbine-driven units are substituted for cross-compound with a saving in first cost, and an increase in cost of opperation.
Initial Investment
2-2,000,000 gal. Turbine-driven Centrifugal Units, complete on foundations, with all connections
20,000.
2-150 H. P. H. T. Boilers 6,000
Setting Boilers 2,500.
Feed Pumps, Heaters etc. 1,000.
New 20 in Suction Line
30,000
Storage Tank, including Land and Connections
36,350.
95,850.
10 per cent for Engineering and Supervision
9,585.
Total Investment
105,435
PLAN THREE
Motor-driven Centrifugal Pumps in Present Station Initial Investment
2-2,000,000 gal. Motor-driven Centrifugal Units complete.
$8,000.
Duplicate Line and Transformers 4,285.
New Suction Line 30,000.
500,000 gal. Storage Tank with Land and Connections 36,350.
Heating System 500.
79,135.
10 per cent. for Engineering and Supervision
7,914.
Total Investment 87,049.
PLAN FOUR
Cross-Compound Steam Pumps in New Station
This plan involves erection of a new station and boiler house on the shore of Great Pond and a force main connecting this station with a 500,000 gallon storage tank near by, and with the main dis- tribution system on Hollis Street. The cost of the new station is largely offset by the saving of the entire cost of the 20 inch suc- tion main which will not be needed under this plan.
34
Initial Investment
2-2,000,000 gal. Cross Compound Units, complete on Foundations
$32,880
2-150 H. P. Boilers with Settings
9,000
Boiler House
10,000
Pumping Station
11,510
Coal Storage
1,000
Stack and Connections
1,500
Feed Pumps, Heaters, etc.
1,000
500,000 gal. Storage Tank and Connections
30,000
Force Main
7,200
Land Taking
2,000
Road
500
Suction and Discharge Fittings, By-pass to Gravity, etc.
5,000
111,590
10 per cent. for Engineering and Supervision
11,159
122,749
PLAN FIVE
Turbine-Driven Centrifugal Pumps in New Station Initial Investment
2-2,000,000 gal. Turbine-driven Centrifugal Units, complete
$20,000
2-150 H. P. Boilers
6,000
Setting Boilers
3,000
Feed Pumps, Heaters, etc.
1,000
Boiler House
10,000
Table 4 Cost of Improving Present Pumping and Storage System
Plan No.
Description
Invest- ment
*Opera- tion
Bonds and Interest
Total
1st Year
Average
1st Year
Average
1
2-2,000,000 gal. Cross-Compound Pumps in Old Station with New Suction Main and 500,000 gal. Stor- age Tank
$123,112
$7,469
$11,095
$8,017
$18,564
$15,486
2
2-2,000,000 gal. Turbine-driven Centrifugal Pumps in Old Station, New Suction Main and 500,000 gal. Storage Tank
105,435
7,886
9,694
7,058
17,580
14,944
3
2-2,000,000 gal. Motor-driven Cen- trifugal Pumps in Old Station, New Suction Main and 500,000 gal.
Storage Tank
87,049
8,248
7,654
5,489
15,902
13,737
4
2-2,000,000 gal. Cross-Compound Pumps in New Station with 5,000,000 gal. Storage Tank and Necessary
Force Main
122,309
7,469
11,043
7,974
18,512
15,443
5
2-2,000,000 gal. Turbine-driven Centrifugal Pumps in New Station, 500,000 gal. Storage Tank and Nec- essary Force Main
108,570
7,886
10,002
7,278
17,886
15,164
6
2-2,000,000 gal. Motor-driven Cen- trifugal Pumps in New Station, 500,000 gal. Storage Tank and Nec- essary Force Main
73,134
8,248
6,494
4,677
14,742
12,925
V
*Coal at $9.50 per ton. Current as per present Contract.
Annual Charges
36
Suction Well & Pumping Station
11,500
Coal Storage 1,000
Stock and Connections 1,500
Suction and Discharge Fittings, By-pass to Gravity, etc.
5,000
500,000 gal. Storage Tank with Connections Land Taking 2,000
30,000
Road
500
Force Main
7,200
10 per cent. for Engineering nad Supervision
9,870
108,570
PLAN SIX
Motor-driven Pumps in New Station
Initial Investment
2-2,000,000 gal. Motor-driven Centrifugal
Pumping Units, complete
8,000
Duplicate Line and Transformers
4,285
New Station Complete 9,000
Suction and Discharge Fittings, By-pass to Gravity, etc.
5,000
500,000 gal. Storage Tank
30,000
Land Taking
2,000
Road
500
Force Main
7,200
Heating System
500
66,485
10 per cent. for Engineering and Supervision
6,649
73,134
The total annual charges for operation bond payments and in- terest under each of the above plans, is shown in Table 4. The bond payments are figured on the 30 year serial bases in all cases where the life of the structure is 30 years and over. In cases where the life of the structure is less than 30 years, the payments are figured to retire the bonds within the life assigned.
Tables 2 and 4 show that regardless of location of station, the use of electric current will apparently effect a saving of about $1,000.00 per year, under present conditions.
I cannot see how the saving can be less in the long run, since the estimates for electrical operation are based on the actual re- sults now being obtained, while those for the two types of steam plants are based on duties obtainable from new equipment, with the best of coal, and working conditions, so that while it is com- paratively easy to keep the electric units up to their present effi- ciency, the proposed steam units are sure to show decreased effi- ciency and increased operating costs as they grow older.
As to the location of electric units, we must choose between Plan 3 the costs of which are definitely established and Plan 6 which involves new buildings and new foundations, with an element
98,700
37
of possible unforeseen difficulties and consequent increase in costs.
Considering the substantial character of the present station, and its convenient situation, coupled with the fact that it also houses the steam plant which with electrical operation will be held in reserve, it does not seem to me advisable to make a change for the sake of a possible, but not assured saving of seven or eight hundred dollars per year.
I have therefore taken the costs of Plan 3 as representing the necessary future expenditures on the present system for pumping equipment, suction lines and storage.
In this connection, I wish to emphasize the fact, that, allowing for all possible contingencies that might effect my estimates, the greatest possible difference in cost between any of the plans con- sidered, could not possibly be a determining or even an influencing factor in the ultimate comparison of the cost of local service with that of the Metropolitan.
(b) Additions to the Distribution System
If Great Pond is to be retained as a source of supply, pipe capacity to the northern portion of the town must be increased.
The 14 inch gravity main was designed to provide normal domestic service, with very low pressure on the high parts of the gravity system.
It will still, due to the great reduction in consumption effected by the installation of meters, furnish this normal domestic con- sumption, but with such a slight margin that any slight increase due to abnormal use of lawn hose, or speeding up on the part of manufacturing plants drops pressure to a point where the higher parts of the system are without water.
This main is about 14,000 ft. in length, is laid for a large part of the way through swampy country where there is no population. Its duplication would be the most expensive and least satisfactory way out of the difficulty.
It was customary in the past, when pressures were too low on the gravity, to pump to that system, thereby raising the pres- sure by about 40 lbs.
This, too, is rather extravagant as it means pumping at the rate of one thousand gallons per minute or over, when the actual amount required to boost the gravity system is seldom over one hundred fifty gallons per minute.
During the last four or five years, we have attempted to handle the situation by opening a valve from the high service in East Weymouth and admitting the necessary amount to boost the gravity. This would work out very well if it were not for the fact that the high service feeder is so' small, (6 in. from South Weymouth to Lovell's Corner) that the drawing of this small quantity is apt to cripple the service. Due to this small feeder, fire service between East Weymouth and Columbian Square is inadequate, and moreover, in case of a break in the 14 in. gravity line, this small line down Pleasant St., and the other small line to Weymouth Landing would hardly supply the normal requirements of the northern end of the town, to say nothing of furnishing fire protection.
To overcome all the difficulties and obtain still further bene- fits with the least outlay, a 12 in. main should be laid from South Weymouth to Lovell's Corner via Park, Pine and Pleasant
38
Streets. It may be desirable later to extend this line to East Wey- mouth, or through Washington St., to connect with the 14 in. at Middle St., and from there to Weymouth Landing but the neces- sity for such an extension will not probably be felt for quite a number of years and need not be considered in the present esti- mates.
The beneficial results of the line as proposed to Lovell's Cor- ner would be as follows:
(1) Provides adequate service on Park and Pine Streets which is being demanded by residents on these streets at the present time.
(2) Strong fire service all along Pleasant Street to East Weymouth.
(3) Reserve line capable of supplying East Weymouth, Wey- mouth and North Weymouth in case of failing of gravity line.
(4) Increase fire service at East Weymouth, Weymouth and North Weymouth to meet the standards of the insurance interests.
(5) Elimination of trouble with domestic service on gravity line by the use of small amounts of pumped water, rather than pumping to the entire system.
(6) It is also interesting to note that in case a ground water supply were developed along Old Swamp River, this main would serve as a force main to South Weymouth standpipe.
At the present prices the cost of this feeder would be about. $43,000. which would entail an average annual charge for interest and bond payments of $2,508.00 the charge for the first year being $3,583.00.
IV Quality of Great Pond Water and Cost of Purification
All improvements so far mentioned in this report have had to do with available quantity and pressure.
I find that there is in some quarters, a decided dissatisfaction with the quality of Great Pond water and in order to make a fair comparison between this supply and that of the Metropolitan it will be necessary to take into consideration the methods and costs of bringing the quality of the local supply up on to a parity with the Metropolitan.
From a strictly sanitary standpoint, the Great Pond supply is at the present time absolutely satisfactory. The water shed is sparsely populated and under the constant supervision of the water department. No case of contagious disease has ever been traced to, or even remotely ascribed to water supply in this town, and the chemical analysis does not show any significant increase in those substances which are taken as indices of pollution.
Increase in free ammonia from .0000 in 1892, to .0048 in 1912, has been sited in the past as evidence of increased pollution. The fact however, that one of the first samples analyzed in 1883, gave a free ammonia content of .0020 while in 1917 the average was as low as .0012 strengthens my belief that there has been no progres- sive deterioration, and that a great part of the ammonia content is a result of the decomposition of harmless microscopic organisms in the pond itself rather than of pollution from the water shed.
39
Regardless of what analysis may show, however, there is always a potential danger so long as there are human habltations on the water shed. This danger may be said to exist even though the sources of possible pollution are far from the reservoir itself, but when they are on the very shores, it becomes a grave one.
For this reason I believe it to be essential, if the Great Pond supply is to be retained without purification for the town to ac- quire at least the properties abutting directly upon the pond.
With the shores under the absolute control of the water de- partment and the water shed subject to the joint supervision of the water department and State Board of Health, I believe that the water of this pond could be kept in a safe condition without filteration.
The complaints of consumers, regarding the water however, are not of its condition from a sanitary standpoint, but mainly of its appearance. Due to the large areas of undrained swamps on its water shed and the heavy growth of grass and diciduous trees along its shores, Great Pond furnishes a water of a relatively high color and carries a considerable amount of vegetable matter in suspension.
That these characteristics' in a water supply are objectionable cannot be denied. They are more or less repulsive to the refined taste and tend to give the erroneous impression that the source is unclean and perhaps polluted. Twenty years ago when many communities were using water of the color of weak tea without complaint, this Great Pond Water would have been considered ex- ceptionally good. It has not deteriorated since then, but the taste of the consumer in this, as in many other things has become more refined, and his demands more exacting. The water supply pro- fession today recognizes the fact that it must supply a water which is not only safe but clear and sparkling and pleasing to all the senses.
Th only process by which Great Pond water can be brought up to thse standards, is that of coagulation with alum and rapid filteration through sand. Slow sand filteration without chemicals would remove this suspended matter and most effectively take care of any possible disease-breeding bacteria, but the filtered water would still have sufficient color to cause dissatisfaction among the consumers.
This is a point that I wish thoroughly understood: that color- less water from Great Pond means chemical treatment.
I have drawn tentative plans for a mechanical filter plant of 2,000,000 gallons daily capacity, using alum as a coagulant and estimate the cost of filters, sedimentation and clear water basins complete with low lift pumps for pumping on to filters, at $70,000. The annual cost for operation of such a plant at present prices would be about $8,000 per year.
In connection with this matter of quality and filteration I wish to warn the water consumers of Weymouth against making the common mistake of thinking that filteration, or the introduction of the Metropolitan supply will do away altogether with the ap- pearance of dirty, rusty and high colored water at the faucets.
I believe that the greater number of complaints regarding the Great Pond water relate, not to the characteristics of the water as it leaves the pond, but to certain characteristics that are acquired during its journey from the intake to the individual faucet.
40
In nearly all water, both surface and underground, iron is present in varying quantities. The iron content of Great Pond water is considerable less than that which is generally considered as allowable in good and satisfactory supplies; so long as it re- mains in solution it is unnoticeable and harmless. If however, as is usually the case, it enters the main in solution, it is very likely to oxidize to an insoluble form and settle to the bottom of the pipe at points where the velocity is low.
When the velocity is increased by flushing, use of water at fires, or to fill sprinkler carts and spraying machines, this deposit is stirred up and drawn through the house fixtures, to the disgust of the consumer and sometimes with disastrous results in the laundry.
In addition to the iron brought into the system in solution, there is a continual process of pipe corrosion going on accom- panied by solution of iron and its subsequent precipitation, to make trouble when the velocity is for any reason increased be- yond the usual.
While this corrosion takes place in a certain degree in the cast iron mains the greatest source of trouble lies in the wrought iron service pipes, the wrought iron pipe in the houses, cast iron water fronts and galvanized boilers. Corrosion is exceptionally active in the hot water system and a small deposit of iron in tank or water front will furnish "red water" until completely flushed out. Probable 90 per cent. of the complaints investigated can be traced to corrosion between the street main and the faucet, or to old street mains of wrought iron. The use of cement lined service pipes and of brass piping in the house would do away with a great part of the trouble.
It is probable that the rate of corrosion, and the consequent precipitation of iron, together with the deposits of suspended matter would be much less with the Metropolitan supply than under present conditions .*
With mechanical filtration the suspended matter would be practically removed, but it is probable that corrosion would be considerably increased.
Granting, however, that in either case conditions would be greatly improved, the point that I wish to emphasize is, that, neither Metropolitan supply or filtration will afford absolute immunity from the troubles due to the stirring up of deposits in the mains.
*It has recently come to my attention, that during the summer of 1921, the Milton Water Department has had a great deal of trouble with dirty water. Milton has Metropolitan supply.
V METROPOLITAN SUPPLY
The Metropolitan District Commission offers to supply water from their southern extra high service station at Hyde Park through about 12 miles of pipe line to the Braintree-Weymouth line, at a pressure equivalent to 250 ft. above mean low water in Boston. Harbor.
This would furnish water of an excellent quality, at suitable pressure, for Weymouth, East and North Weymouth ( with prac- tically no changes in the distribution. Direct service could also be furnished along Washington and Main Streets as far as Winter
41
Street and up Pleasant Street, probably as far as Park Ave. The territory south of these points would have to be supplied by dupli- cate booster pumps which could be located in the present station on Hollis street. These pumps would work in conjunction with the present standpipe and should have a combined capacity some- what in excess of the maximum daily consumption of the town, so that in case of a break in the Metropolitan main they could supply Great Pond water for both domestic and fire purposes.
The terms for entering the Metropolitan system are as follows:
Payment to the District of an entrance fee of $500,000 which is based on extra cost of construction which the district must incur in order to serve Weymouth.
If the town of Braintree will enter the District at the same time, this initial payment will be reduced to $370,000. I have every reason to believe that Braintree will enter if Weymouth does.
Need help finding more records? Try our genealogical records directory which has more than 1 million sources to help you more easily locate the available records.