Hampton Sewer Department History -- 1954

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143 Winnicunnett Road
Hampton, N. H.
December, 22 , 1954

Mr. Leavitt Magrath
Sewer Department
Hampton, N. H.

Dear Sir:

Our Social Studies class is seeking information having to do with town government. We are doing this in preparation for a Unit to be studied during the first weeks of March.

There is very little information available concerning this subject. Therefore, we are asking each town official if he or she would supply us with information concerning the position that they hold. An outline is included that may, if you wish, be used as a guide.

We would appreciate having this request filled by January 10, 1955, in order that it may be prepared for duplication.

Thank you very much for your kind consideration and cooperation.

Pauline Wiggin


1. How you receive your job -- whether you are elected or appointed.
2. How long you serve at this job.
3. Your approximate salary.
4. A few of the duties and responsibilities connected with your job.

December 31, 1954
Miss Pauline Wiggin
Winnicunnet Road
Hampton. N. H.

Dear Miss Wiggin:

In reply to your letter of December 22, I would like to say that I was appointed by the Selectmen to supervise and maintain Sewer Disposal Plant in April 1935. Have served ever since -- 20 years in April 1955.

Approximate Salary -- Was $25.00 a week when I started and increased through the years as the plant was enlarged. Now it is $72.60 a week.

Duties and responsibilities are many. Keeping all pumps and motors in perfect running condition 24 hours a day, 7 days a week. At the Beach pumping station we have three pumps, a chlorinator, a comminuter, automatic switches which have to be checked everyday, and recording meters that tell the quantity flow of sewage, which is important in knowing how many pounds of chlorine to be put in every 24 hours.

At the Disposal Plant we have several settling tanks which must be kept clean, so as to give digestion of the sewage its proper digestion qualities and settling abilities. We have a large filter bed with probably 340 individual spray nozzles which have to be kept clean so they will spray over the proper area. Also, pumps, collectors, etc. and a chlorinator which dozes the sewage effluent with chlorine to purify the water before it finally reaches the creeks and marshes.

Lawns have to be kept mowed, buildings kept painted, and machinery painted each year. In thunder storms or any storm I have to go to the plant day or night to see that pumps are kept running. When power is off the automatic pumps stop, so we have to run another kind till the power comes on, so as to keep tree sewage flow moving.

Responsibility is so great it is hard to explain it. Would be glad to have you visit the plant and I would show you around. Besides all this, I supervise the construction of new sewer lines.

We also make standards for "No Parking" signs, put up Christmas decorations in town and a lot of other odd jobs the Town officials ask us to do.

To carry on these duties it requires 3 to 8 men -- depending on the work.

Hope this has answered your questions.


/s/ Leavitt Magrath
Leavitt Magrath

Town of Hampton, New Hampshire

Memorandum on Sewage Treatment Works

THE ORIGINAL sewage treatment plant constructed in 1934 and placed in operation in 1935 consisted of an Imhoff tank, dosing tank, trickling filter, secondary settling tank and certain pumping equipment and chlorinating apparatus, all designed to serve an estimated population of 10,000 persons on a year-round basis, with special provisions for the greater part of the sewage contributed to the plant arriving during the period between June 15 and Labor Day, and the principal function of the plant up to the present time has been to treat the sewage from Hampton Beach, which is pumped from the Beach area across the marsh to the treatment works which are located on the mainland southeasterly from Hampton Village.

The original Imhoff tank had a settling compartment or flowing through chamber of 63,000 gallons capacity and the digestion compartment directly below the settling chamber has a capacity of 10,000 cubic feet. On the basin of an estimated population of 10,000 persons the detention period in the settling compartment if 1.5 for sewage flows equal to 1.0 agd rate.

The Imhoff tank as originally designed was a rectangular 2-story horizontal reversible flow unit, the reversal flow being effected by stop planks in a control chamber and the settleable solids passed through a trapped slot to inverted phramidal bottom in which the solids digested and from which they were removed by gravity. The gases given off by digestion were vented to the atmosphere through chimneys located along each side of the tank and a central chimney three-fifths of the length of the tank, the area of the gas vents being approximately 23 per cent of the superficial area of the tank.

From the Inhoff tank the sewage flows through a twin dosing tank having protective screens and one 10-inch diameter and 14-inch diameter automatic dosing siphon -- the twin siphons and the variation in diameter being necessary to meet the variation in flow between the height of the summer season at the Beach and that contributed by a small permanent population.

A trickling filter of approximately 0.42 acres in area, having 98(?) feet of crushed trap rock as filter media provides a capacity of 3000 persons per acre roc, an the basis of a connected population of 10,000 people, and the filter is served by a cast iron manifold connection between the dosing tank and the filter, the manifold having 14 lateral distribution pipes with gated connections and fixed spray nozzles.

The trickling filter distribution is so designed that any or all of the 14 lines can be used at one time and in general, with 14 lines in operation and both siphons in use, the capacity of the plant is 1.4 agd; with the 14-inch siphon working alone and 9 of the distribution lines in operation, the plant capacity is 0.8-5 agd. Provision has been made for winter operation, and based on the 10-inch siphon operating alone and 5 of the distribution lines with 72 spray nozzles working, the plant capacity would be approximataly one-half million gallons per day.

The filter stone rests on an underdrain system developed by ridges and valleys in the concrete floor of the tank and there are 21 lines of inverted channel pipe underdrains located in the valleys of the filter floor and vented through cast iron soil pipe risers at the upper end and discharging to an open collecting channel located along the westerly aide of the filter.

The original layout included a secondary settling tank located in the effluent line from the filter and design to intercept such solids as might pass the filter, and particularly to prevent the discharge of solids to the stream during the periods of periodic unloading of the filter media.

Removal of the secondary tank solids was affected in the original design by suction centrifugal pumps located in the pump house adjacent to the tank and the removed solids were discharged through a force main to the digesting compartment of the Imhoff tank.

Provision was made in the original installation for chlorinating the sewage affluent and chlorine was applied at the inlet and of the secondary settling tank which served as a combined settling tank and contact chamber.

In 1950 certain improvements were made at the treatment works to increase the capacity of the plant to provide not only for the growth which had taken place at Hampton Beach during the past 15 years, but to provide for the sewage from Hampton Village which is collected by a system of 6 miles of main and lateral sewers, also constructed in 1950.

The treatment plant improvements included the construction of a rectangular horizontal flow primary settling tank about 18 feet x 36 feet, in plan dimensions and having a water depth of 10 feet and complete with longitudinal and cross collecting mechanism, provision for continuous removal of settled solids and a skimming device. This additional settling capacity provides, together with the capacity remaining in the original Imhoff tank, for 1.5 hours retention period when the treatment works are operating at the rate of 1.8 agd.

Certain improvements were affected in the plant piping and motoring equipment was installed to provide a record of plant operation and a double overflow weir was installed at the outlet end of the original Imhoff tank to reduce the overflow rate.

Additional secondary settling tank capacity was provided by the installation of a rectangular horizontal flow secondary settling tank equipped with flights for the continuous collection of sludge, and provisions were also made for the automatic withdrawal of the settled solids continuously.

In affect the secondary settling tank capacity consists of 3 independent tanks, the original tank being divided into two units and supplemented by the previously described additional tank with mechanical equipment.

The chlorinating apparatus has been retained and routine operation includes chlorination, and it is also possible by increasing the does of chlorine to provide chlorinated mesh water for reduction of plant odors and fly nuisance.

As previously stated, provision has been made in the last improvements for treating the sewage from Hampton Village and in this connection a comminuter has been installed in the suction well of the original plant installation, and two horizontal, electric motor driven suction centrifugal pumps have peen installed in the pump house, located at the secondary settling tank. The sewage reaching the plant from Hampton Village is lifted to the inlet end of the new primary settling tank and a common force main is provided for the sewage from Hampton Beach and that entering the plant from Hampton Village.

In the original treatment plant layout, sludge drying beds were having [eligible] square feet of sand area, but is [eligible] have never been used on account of the availability lagoon area for the disposal of sludge, no additional sludge drying area was included in the treatment plant improvements.

The operating difficulties experienced in the past when the variation in sewage flow ranged from upward of 15,000 persons during the height of the summer season, to the flow occasioned by several hundred permanent residents at the Beach, plus leakage during the off season months will to some extent be relieved by the addition of sewage from Hampton Village and it is quite possible that the addition of the Village sewage will result in a more satisfactory overall plant effluent being developed from this time forward.

The combination of salt water infiltration into the sewers at Hampton Beach, combined with decomposing domestic sewage has resulted in highly corrosive conditions, and metalwork in the pumping equipment and in the plant control devices has suffered from this action, and certain parts of the concrete structural units have also been seriously affected by the corrosive action of the combined sewage and salt water, and to counteract this action, natural or Rosendale cement was used in the concrete for the structural units in the plant improvements and an attempt is to be made to prolong the life of the metal parts by preventive maintenance in the form of Bitumastic Enamel Paint.

[Courtesy of The American City Magazine
The Municipal Index
Contractors and Engineers
The American School and University
The School Executive - School Equipment News]
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