Before the tentative standards for opening-closing of these beaches were promulgated, it was recognized that when winds blew from the north, even during dry weather, movement of polluted harbor water would take place to the south and affect South Shore and Bay View Beaches. The higher the wind velocity the more rapidly the water moves. As a compensatory factor is the fact that when winds of high velocity blow from the north few, if any, bathers frequent the beaches and practically none enter the water. III. RESULTS OF APPLICATION OF TENTATIVE STANDARDS FOR OPENING-CLOSING OF BEACHES The tentative formula, originally promulgated in 1963, has not since been altered. South Shore and Bay View Beaches were reopened in 1963 and remained open in 1964, 1965, and 1966. During the bathing season of each of these 4 years, both beaches were intermittenly opened and closed to public use during time intervals arrived at by application of the tentative or proposed standards. (For the proposed standards see exhibit 1.) Application of the proposed standards has served to accomplish the desired objective quite well during the past four bathing seasons at South Shore and Bay View Beaches. Beach water samples were collected at these two beaches at about 6 a.m., 8 a.m., 10 a.m., and 12 noon, on a daily basis during the entire 1965 and 1966 official public bathing seasons. (Three separate samples were collected from closely adjoining locations at South Shore Beach at the 6 a.m. sampling hour.) Exhibit 2 and exhibit 3 summarize pertinent data for 1965 and 1966 for South Shore and Bay View Beaches. The basic data in these two exhibits have been extrapolated from more detailed data set forth in exhibits 4 through 7. IV. POLLUTION AT M'KINLEY AND BRADFORD BEACHES McKinley and Bradford Beaches adjoin each other and are located immediately to the north of the breakwater which tends to confine the highly polluted waters of Milwaukee's outer harbor. McKinley Beach is located more proximately to the breakwater than is Bradford Beach. There are three major openings in the breakwater which permit harbor waters to leave the outer harbor and enter directly into Lake Michigan. Peculiar and unusual combinations of wind direction must occur in order to move polluted harbor waters so they reach these two beaches. In general, a south or southwest wind direction is necessary to move polluted water from the harbor into the lake, and then a wind shift to the southeast is necessary to move the water toward the two beaches. The great variability of wind direction makes it impossible to develop a meaningful standard, which could be realistically employed, to predict when these beaches might be subjected to undesirable levels of pollution by fecal coliform organisms. Accordingly, these beaches have not been subjected to periodic opening and closing as have been South Shore and Bay View Beaches. McKinley and Bradford Beaches have been closed occasionally because decaying masses of algae (Cladophora glomerata) have rendered these beaches esthetically objectionable. Fecal coliform data for McKinley and Bradford Beaches for 1965 and 1966 are set forth in exhibits 8 through 11. During this 2-year period both beaches were open for 159 days. During these 159 days, McKinley Beach showed fecal coliform-membrane filter counts of 1,000 or more per 100 milliliters on only 3 days (1,270, 2,630, 1,240). During the same 159 days Bradford Beach also showed counts of 1,000 or more per 100 milliliters on only 3 days (1,690, 2,630, 1,050). THE PREDICTIVE VALUE OF STANDARDS FOR OPENING-CLOSING OF The tentative standards employed from 1963 through 1966, to determine when South Shore and Bay View Beaches should be closed to bathers, have served very successfully to deny use of these beaches to the public when high fecal coliform organism concentrations occurred. (See exhibits 2 and 3.) In spite of this generally successful application of the standards, there have been occasional failures to accomplish the total objective. To illustrate, South Shore Beach was open on a total of 5 days during 1965 and 1966 when the fecal coliforms exceeded 1,000 per 100 milliliters (1,240, 2,482, 2,630, 3,638, 4,050). Bay View Beach was open on only 1 day during 1965 and 1966 when the fecal coliforms exceeded 1,000 per 100 milliliters (8,772). There are a number of factors which serve to make the present standards less effective than one would like. These factors are: 1. The combined sewer outfall at the foot of Russell Avenue There is a large combined sewer outfall at the foot of Russell Avenue which empties directly into Lake Michigan at the east end of Russell Avenue. This outfall is located less than one-half mile from the north end of South Shore Beach. The beach closure standards (See exhibit 1) do not provide for closure following rainfall in amounts of less than 0.1 inch. This quantity of rainfall does not generally cause combined sewer outfalls to discharge in Milwaukee. If dis charge does occur, it is small in quantity. Small discharges into the rivers are subjected to great dilution before reaching the beaches. In addition, marked die-off of fecal coliforms results while the polluted river waters flow to the harbor and are then moved to the beach areas. Discharge of comparatively small amounts of pollution in close proximity to a beach is much more serious. This condition could be alleviated by extending the outfall directly into Lake Michigan, outside of the breakwater within which South Shore and Bay View Beaches are located. 2. The Kinnickinnic River flushing station This flushing station is used during the summer months to pump water from Lake Michigan, at the foot of Russell Avenue, into the Kinnickinnic River in order to prevent anaerobic conditions from developing in the river. The discharge outlet of the tunnel is below the river surface and the gates are usually inoperable. Consequently, when the pumps are not operating, highly polluted river water flows from the river into the lake at the foot of Russell Avenue, not far distant from South Shore Beach. The pumping station is antiquated and in need of replacement. When this is done, the station should be so arranged that water pumped into the river is discharged at a level above that of the river, thus eliminating all possibility of backflow when the pumps are not operating. 3. Discharge of Jones Island treatment plant effluent The Jones Island sewage treatment plant discharges its effluent directly into the outer harbor immediately south of the mouth of the Milwaukee River. During dry weather flow, sewage treatment at the plant results in a bacterial reduction of about 93 percent. However, during peak dry weather loads, the plant is overloaded thus reducing the effectiveness of the activated sludge process and causing effluent of a lower quality to be discharged. Although the treatment plant contributes a huge daily volume of pollution to the water of the outer harbor, this is not usually of sufficient magnitude to cause a high degree of water pollution with fecal coliform organisms at the beaches immediately adjacent to the outer harbor. When winds of moderate to high velocity blow directly from a northerly direction for a prolonged period of time, however, harbor water polluted primarily by sewage plant effluent can move to the south and pollute South Shore beach to a moderate degree. An example of this occurred on July 27, 1965, when the fecal coliform count was 1,240 per 100 milliliters. No more than a trace of rainfall occurred between July 17 and July 30. On July 27 the wind blew from the northwest at an average velocity of 8.2 miles per hour. It seems probable that the wind moved harbor water, polluted with sewage plant effluent, toward South Shore beach in sufficient quantity to result in a beach water fecal coliform count of 1,240 per 100 milliliters. Chlorination of the effluent of the Jones Island sewage treatment plant during the bathing season would serve to eliminate this source of pollution of the harbor waters. 4. Use of rainfall recordings at only the Milwaukee Municipal Building as the guide for application of the standards for opening-closing of beaches The standards (see exhibit 1) specify that "the site for determination of time of onset of, duration of, and quantity of rainfall shall be the Milwaukee municipal building." This single site was chosen because Health Department personnel work in this building daily; it is the site of an automatic, continuous recording rainfall gage; and the location is somewhat central in relationship to those sections of the three rivers in Milwaukee, into which combined sewer outfalls empty during periods of heavy rainfall. Rainfall is practically never uniform in time or quantity over an entire city the size of Milwaukee. Significant variability in quantity of rainfall in different areas of the community can seriously invalidate the standards for beach closing based on rainfall recorded in a single location. This was, of course, appreciated prior to the time the tentative standards were adopted in 1963. The significance of this factor may be illustrated by an occurrence at South Shore beach in 1966. On July 26 the rain gage in the municipal building showed 0.55 inch of rainfall between 5:25 p.m. and 7:50 p.m. The beach was closed during the 48-hour period from 7:50 p.m. on July 26 to 7:50 p.m. on July 28, pursuant to the provisions of the standards. The U.S. Weather Bureau gages at Mitchell Airport showed 1.15 inches of rainfall between 5 and 8 p.m. on July 26. If rainfall at this location had been employed as the basis for application of the standards for beach closing, the beach would have been closed from 8 p.m. on July 26 until 8 p.m. on July 29. Using the municipal building rainfall data, the beach was closed on July 27 (fecal count equals 17,800 per 100 milliliters), closed on July 28 (fecal count equals 7,150 per 100 milliliters), but open on July 29 (fecal count equals 2,630 per 100 milliliters). In the future the standards for beach closure will be modified so as to give consideration to rainfall recordings at both the municipal building and Mitchell Field. Duration of beach closure after rainfall will be based on the maximum rainfall recorded at either of the two gaging stations. 5. Alteration of standards for opening-closing of beaches in relationship to small amounts of rainfall The present standards call for closing of South Shore and Bay View beaches for only 12 hours after termination of rainfall in amounts ranging from 0.1 to 0.19 inch. Some data suggest this 12-hour period may be inadequate and may need to be increased to 24 hours. On July 7, 1965, Bay View beach was open and the arithmetic average of duplicate fecal coliform membrane filter counts on samples collected at both 10 an 11 a.m. was 8,772. (Beach officially opens at 10 a.m.). This was by far the highest fecal coliform count ever recorded at either Bay View beach or South Shore beach at a time the beaches were open, pursuant to the provisions of the standards. On July 6, 1965, 0.18 inch of rainfall was recorded between 6:15 p.m. and 7:45 p.m. The standards dictated that the two beaches be closed until 7:45 a.m. on July 7, 1965. The fecal coliform concentrations at South Shore and Bay View beaches on the morning of July 7, 1965, were as follows: The 0.18 inch of rainfall on the early evening of July 6 was sufficient to cause combined sewer outfalls to spill much sewage into the lower reaches of the Milwaukee River and to cause the polluted water to enter the outer harbor. During the night the wind direction was northeast to east at an average velocity of about 7 miles per hour. This would move polluted harbor water in the direction of the beaches. Early on the morning of July 7 the wind shifted to the south and after 9 a.m. shifted to the west. From the foregoing it is reasonable to assume that a mass of polluted water had moved past South Shore beach during the night of July 6 or early morning hours of July 7 and had reached or passed Bay View beach by 6:15 a.m. on July 7. If the polluted water mass had passed Bay View beach, it was probably again moved toward the beach when the wind direction shifted to the south and moved the water toward the north. Noteworthy is the fact that by 12:15 p.m. on July 7 the fecal coliform count at Bay View beach had been reduced to 895 per 100 milliliters and was 218 per 100 milliliters on July 8. If the beach had been closed for 24 hours following 0.18 inch of rainfall, instead of only 12 hours, it would not have been open on July 7, when the high fecal coliform organism concentration prevailed. REFERENCES (1) "A Comprehensive Water Pollution Control Program," Lake Michigan Basin-Milwaukee area. Federal Water Pollution Control Administration, June 1966. (2) "Interim Report of the Special Committee on Water Pollution of the Common Council of the City of Milwaukee." July 31, 1961. (3) "Condensed Report of Results of Milwaukee Health Department's Studies of Sanitary Quality of Bathing Beach Waters Conducted in 1961 and 1962." E. R. Krumbiegel, M.D., Commissioner of Health. February 1963. EXHIBIT 1 PROPOSED STANDARDS TO BE USED AS GUIDE IN OPENING AND CLOSING SOUTH SHORE AND BAY VIEW BEACHES DURING THE 1963 PUBLIC BATHING SEASON RECORDING OF RAINFALL The site for determination of time of onset of, duration of, and quantity of rainfall shall be the Milwaukee municipal building. All such determinations shall be made through the use of automatic, continuous recording equipment. STANDARDS FOR BEACH CLOSURE The beach waters shall be closed to public bathing at all times while rainfall occurs at the beaches. Both beaches shall also remain closed for the minimum time intervals after the amounts of rainfall (as determined at the Milwaukee municipal building) listed below: Amount of rainfall: Number of hours beaches to remain closed after time last rainfall terminates 1 If the amounts of rainfall shown above should occur on consecutive days; or if rainfall on 1 day should be followed by rainfall on any subsequent day, but before the indicated number of hours of beach closure indicated above have elapsed, the total duration of beach closure shall be as follows: Amount of rainfall: Number of hours beaches to remain closed after time last rainfall terminates (a) (1) above on 1 day and (2) above on following day or preceding day--- 36 (8) (2) above on 1 day and (3) above on following day or the preceding day. (c) (3) above on 1 day and (4) above on the following day or the preceding day. 72 96 EXHIBIT 2 Fecal coliform data on samples collected by Milwaukee Health Department, 1965 and 1966 bathing seasons-South Shore Beach Number days in 1965 and 1966 bathing seasons_ South Shore Beach-117.5 open days 159.0 117.5 41.5 26.0 26.0 26.0 Fecal coliform data on samples collected by Milwaukee Health Department, 1965 and 1966 bathing seasons-Bay View Beach Number days in 1965 and 1966 bathing seasons- Bay View Beach-41.5 closed days 159.0 117.5 41.5 26.0 26.0 26.0 |