|In 1988, in response to complaints of rusty water, the Department of Water of the Town of Hempstead conducted a study of the Lido-Point Lookout water system. The study also investigated lead levels in the water supply. The report, with some minor editing, follows. If subsequent work on the water system comes to our attention, it will be posted.|
TOWN OF HEMPSTEAD DEPARTMENT OF WATER
PRELIMINARY INVESTIGATION OF DISTRIBUTION SYSTEM CORROSION PRODUCTS
LIDO-POINT LOOKOUT WATER DISTRICT
The Department of Water has prepared the enclosed preliminary report on discolored water at customers taps in the Lido-Point Lookout Water District based upon the increasing frequency of these complaints, to wit 1988. This problem of discolored water has been a frustrating and long standing problem in the Water District some years being worse than others, the problem previously being moderated by a District bi-annual fire hydrant flushing problem.
This report presents a preliminary assessment of the problem as it currently exists, addresses why the problem exists and suggests various alternatives for further study to ameliorate the problem.
The Department of Water on behalf of the Lido-Point Lookout Water District will conduct an open meeting on November 15,1988 at 8:00 P.M. at Our Lady of the Miraculous Medal Parish Hall, Point Lookout, to discuss the matter of discolored water at which time copies of the enclosed report will be distributed.
In addition to the placing of posters within the District announcing this meeting various civic associations were contacted directly. These include two Lido Beach Civic Associations, the Point Lookout Civic Association and the Lido-Point Lookout Fire District.
It is hoped that the Department of Water through this and subsequent meetings will be able to establish an effective dialogue with customers of the Water District and together a joint resolution of the problem be effectuated.
Research by the Department of Water into the age of unlined cast iron water mains in the Point Lookout and Lido areas indicates average ages of 58 years for Point Lookout and 54 and 69 years for Lido depending on reality development in that area.
The early water supply for the Point Lookout area was derived from a shallow well installed around 1928/1929 with a small! wooden elevated tank providing storage. A photograph of this well and tank is included in the report and is titled "Point Lookout Water Works - 1929, William Cotter, Plant Superintendent". It is not known if disinfection of the well water was provided, however, it is known that no corrosion control (Ph adjustment) was provided and that the well water would most probably be found to be both soft and aggressive.
Water supplied to the Lido area commencing with reality (sic) development in the late twenties was supplied by the City of Long Beach which treated the water to remove iron, followed by passage through filters containing calcium carbonate (calcite). These filters provided removal of oxidized iron and to a limited extent provided corrosion control (Ph adjustment).
Returning to the Point Lookout area, improvements to the water supply for this area were made in 1936 and 1937 and are described in this report,and include a 1,200 foot deep well (Lloyd formation) a pressure filter for iron removal (calcite) a concrete ground storage tank and associated pumps .These improvements were made by the Lido Point, Inc. Water Company, a privately held company. The calcite filter was required to remove naturally occurring iron found in the Lloyd formation and provided limited corrosion control. A review of an operator log from the year 1941 indicates numerous operating problems with the treatment process with accompaning (sic) complaints of dirty water.
In 1952 the Lido Point, Inc. Water Company was acquired by the Lido Water Works Corporation and subsequently in 1954 the Corporation was purchased by the Town of Hempstead and whose assets were made part of the Lido-Point Lookout Water District which was formally established on 10/5/54.
With the construction of a second deep well in 1955 the newly formed Water District in addition to providing treatment for iron removal provided corrosion control through the use of lime and disinfection by using liquid sodium hypochlorite.
Installation of transmission water mains by the District provided the means of transferring this treated water to both the Point Lookout and Lido areas. It appears reasonable to state that for the period commencing in the late twenties to 1955 water supplied to the Point Lookout and Lido areas receivedlittlee or no treatment for corrosion control, a period of some sixty years.
To help improve the condition of water distributed to the customers tap, the District in 1962 cleaned a portion of the cast iron water mains in the Point Lookout area. This cleaning was limited to scraping the interior of the cast iron water mains and did not include providing a protective cement mortar coating following the cleaning. Unfortunately without th is protective coating corrosion of the cast iron water mains would continue, the use of corrosion control by the District now limiting the rate of corrosion.
The Lido-Point Lookout Water District has some 25.3 miles of water mains almost all of which are unlined cast iron and which because of their age and lack of the practice of corrosion control prior to 1955 today produce discolored water complaints whose frequency is such as to require corrective action by the District.
It should be noted that the problem of discolored water in the District is also related to the water service lines serving District customers. The District presently serves a total of 1,732 customers of which 1,238 or 71.5 have iron pipe services connecting the customer to District water mains. The ages of these iron pipe services within the District are similar to the ages of the unlined cast iron water mains previously referred to. For the I most part these iron pipes services are badly corroded and along with unlined cast iron water mains produce discolored water complaints in addition to restricting flow.
Of the 836 customer accounts in Point Lookout 757 are estimated to have iron pipe services and of the 896 customer accounts in Lido Beach 481 are estimated to have iron pipe services. This information is provided in the report.
Final resolution of the discolored water problem will require taking into account these iron pipe services.
With the increasing number of complaints of discolored water received by the Department in 1988 from the Lido-Point Lookout Water District the Department reviewed and analyzed all discolored water complaints from the District for the years 1986, 1987 and 1988 (up to 8/10/88) which are included in the report.
Analysis of such complaints for this period were made for the entire District and its component areas of Point Lookout and Lido Beach. This analysis was made first by street location and then by months. A map of the District is included in· the report with streets shown in red indicating receipt by the Department of a total of ten or more complaints for the years 1986, 1987 and 1988.
The breakdown of complaints indicates the problem to be more pronounced in the Lido area with the year 1988 by far having the largest number of complaints throughout the District. As expected for each year of the period in question the greatest number of complaints were received during the months of May, June, July and August when water usage is at its greatest.
In 1987 the Department of Water introduced sprinkling regulations as a water conservation' measure. These regulations consisted of odd-even day sprinkling and no sprinkling on any day between the hours of 10: 00 A.M. to 4:00 P.M. This program commenced at mid-year and as a new program there was limited customer participation. In 1988 as the result of various informational type programs and enforcement both by the Department of Water and the County of Nassau greater customer participation was noted.
Because of the limited size of the District's distribution system coupled with the deteriorated condition of the unlined cast iron water mains and iron pipe services the new sprinkling regulations created unusual flow patterns and surges within the system. As a consequence, the number of discolored water complaints increased dramatically, which is especially noticeable during the summer period. Once the distribution system is distrubed (sic) and continues to be distrubed (sic) without the opportunity for recovery (quiescent conditions) discolored water problems will persist.
As previously mentioned the District ,:routinely performed bi-annual flushing of the system, however with the advent of the new sprinkling regulations the amount of water flowed from the District's fire hydrants was reduced, thus limiting the effectiveness of the flushing. This reduction in flushing water is considered to have a contributory effect on the increased number of discolored water complaints.
A review of Department of Water complaint records for the District prior to 1986 indicates a limited number of complaints of discolored water, these complaints following a pattern similar to that found in the report. It is anticipated that as a result of the continued aging of the distribution system and services, sprinkling regulations and flushing limited by water conservation, the problems of discolored water will no longer be manageable and other means to control discolored water must be considered.
The problem associated with the District's unlined cast iron water mains and iron pipe services is quite evident visually to District customers. Unbeknown to most customers is the large number of lead pipe connections between the cast iron water main and iron pipe services commonly referred to as lead goosnecks. Use of the lead gooseneck connection at one time was quite common, however this type of connection is no longer used.
To determine if through corrosion lead was being contributed to water flowing from the customer tap the Department of Water recently conducted in conjunction with the Nassau County Department of Health a series of tests. These tests were performed at a residence located at 54 Glenwood Avenue, Point Lookout, New York. The residence in question is approximately 56 year old, being built in 1932.
The testing consisted of collecting some 90 water samples on a continuous fill and draw basis so as to completely displace the content of the iron pipe service and lead gooseneck serving 54 Glenwood Avenue. The results of this testing indicated that all water samples were found to have lead levels less than 10 parts per billion, the detection limits of the Town's Laboratory equipment. The current New York State Health Department standard for Lead (PB) is 50 parts per billion although reduction of this standard is currently being considered by the United States Environmental Protection Agency. Information relating to this study is contained in the report.
It is estimated that the number of lead goosenecks in the District is the same as the number of iron pipe services in the District which is 1,238 or 71.5% of the District 1,732 customers. In the long term it would be desirable to remove all lead gooseneck connections from the District which most probably would accompany the replacement of iron pipe services with copper.
THE PROBLEM IN SUMMARY
The problem of an aging distribution system heretofore has not been actively addressed in the Lido-Point Lookout Water District. With the onset of increasing customer complaints it is now necessary to consider various options heretofore not considered. The use of an active flushing program which was cost effective and produced reasonably good results can no longer be counted on to produce the desired results as previously noted. Any other solution to the problem must bear a cost to the district customer, the question of cost vs remediation of the problem will be a decision that ultimately the customer and the District will be faced with.
A brief review of the distribution problems which the District is faced with would be as follows:
PROBLEM RESOLUTION - SHORT TERM
To provide an improvement to District water quality in reducing discolored water complaints and reducing the potential for lead solubility is to incorporate in the current treatment process the use of inhibitors. Such inhibitors fall into the category of orthophosphate, polyphosphates and silicates, all of which in general are approved by the New York State Department of Health for use in potable water systems. Their use is not considered as a cure all but have been shown to be effective in reducing customer complaints.
Currently there are a number of water utilities in Nassau County which utilize polyphosphates in the treatment process. More often then not the use of a polyphosphate is to sequester (prevent oxidation to the insoluble form of iron) where iron is found in the supply source. The use by the District of an inhibitor would be to alleviate discolored water problems that occur from the distribution system rather then the supply source.
The Department of Water is currently evaluating the use of various inhibitors; costs of equipment and annual operating expense. The results of this investigation will be reported at a future meeting with District customers. The use of an inhibitor by the District should this methodology be employed is such that the treatment process could be in place prior to the 1989 summer season.
It should be borne in mind that with the use of an inhibitor the District has not resolved the problem completely and is still faced with clogged iron pipe services, external corrosion of iron pipe service and the presence of lead gooseneck service connections.
PROBLEM SOLUTION - LONG TERM
A permanent solution to correct the problems of discolored water would require either the cleaning and cement lining of unlined cast iron water mains or their replacement. This remediation would not address the problems associated with iron pipe water services or lead bends (goosenecks).
To determine the costs associated with either cleaning and lining or replacement of District water mains the Department retained the services of S. Bowne and Son, Consulting Civil Engineers. In addition, S. Bowne & Son was requested by the Department of Water to prepare cost estimates for replacement of iron pipe services and lead bends. In the initial cost evaluations the Department of Water directed S. Bowne & Son because of time constraints to provide such studies of the Point Lookout area only. Further studies will be made by S. Bowne & Son to also include the Lido Beach area. A copy of the report by S. Bowne & Son covering the Point Lookout area is included as part of the Departments report.
S. Bowne & Son has estimated that $2,267,000 would be required to clean and cement line all cast iron water mains in the Point Lookout area. The cost to replace all cast iron water mains, iron pipe services (up to the property I ine) and lead bends in the Point Lookout area is estimated to be $3,213,000. It should be noted that approximately one third of this cost is associated with pavement restoration. Replacement of the iron pipe water service line from the property line to the customer's residence would be the customer1s responsibil jty. A District customer with a home assessed at $7,500 would be required to pay $114 more a year to finance a capital outlay of $3,214,000.
The Department of Water has prepared a preliminary report on the problem of discolored water in the Lido-Point Lookout Water District. The report provides an explanation of the causes of the problem and possible solutions both short and long term.
Further studies of the problem will be carried out by the Department as expeditiously as possible. After completion of these studies the Department will again meet with interested parties to arrive at a concensus for a program to alleviate the discolored water condition.
TOWN OF HEMPSTEAD DEPARTMENT OF WATER
ANALYSIS OF RUSTY WATER COMPLAINTS FOR THE YEARS 1986, 1987, 1988
LIDO-POINT LOOKOUT WATER DISTRICT·
1988 data is as of 8/10/88
LIDO-POINT LOOKOUT WATER DISTRICT
RUSTY WATER COMPLAINTS - POINT LOOKOUT
LIDO-POINT LOOKOUT WATER DISTRICT
GENERAL INFORMATION PRIOR TO AND JUST FOLLOWING FORMATION OF THE DISTRICT
GENERAL INFORMATION FOR THE PERIOD ENDING 12/31/87
*Per Hundred Dollars of Assessed Valuation
Includes 172 Sprinkler Meter Accounts
LEAD GOOSENECK WATER SERVICE LINE CONNECTIONS AND ASSOCIATED IRON PIPE WATER SERVICE LINES
LIDO-POINT LOOKOUT WATER DISTRICT.
*9/20/88 - As per information furnished by D. McNair, Plant Supervisor
ANALYSIS FOR THE PRESENCE OF LEAD AT 54 GLENWOOD AVENUE, POINT LOOKOUT, NEW YORK
LIDO-POINT LOOKOUT WATER DISTRICT
DATA RELATING TO THE SAMPLING FOR THE PRESENCE OF LEAD AT 54 GLENWOOD AVENUE A PRIVATE RESIDENCE AT POINT LOOKOUT, NEW YORK