HINSDALE SCHOOL DISTRICT SWIMMING POOL AUDIT€¦ · general, the pool is in good condition and if...

HINSDALE SCHOOL DISTRICT SWIMMING POOL AUDIT

Hinsdale Central High School Hinsdale South High School

December, 2016

December 2016 2 Hinsdale Township

Table of Contents

EXECUTIVE SUMMARY .................................................................................................... 3

HINSDALE CENTRAL - GENERAL INFORMATION .......................................................... 8

HINSDALE CENTRAL - CONDITIONS AND RECOMMENDATIONS ................................ 9

HINSDALE CENTRAL - MECHANICAL CONDITIONS AND RECOMMENDATIONS ...... 17

HINSDALE SOUTH - GENERAL INFORMATION ............................................................ 26

HINSDALE SOUTH - CONDITIONS AND RECOMMENDATIONS .................................. 27

HINSDALE SOUTH - MECHANICAL CONDITIONS AND RECOMMENDATIONS .......... 36

OPINION OF PROBABLE CONSTRUCTION COST ........................................................ 43


EXECUTIVE SUMMARY

On November 30, 2016, Counsilman-Hunsaker performed two swimming pool audits for the Hinsdale School District. This report is based on the visual observation during the site visit, and conversations with and information provided by Hinsdale staff. The audit included pools located at Hinsdale Central High School and Hinsdale South High School. The purpose of a swimming pool audit is to identify items that are substandard in the pools, identify items not meeting current industry swimming pool design standards, or equipment not operating as designed, and to assist in defining a course of action regarding the future of the pools. In addition, an opinion of probable construction cost is provided for recommended repairs which will bring the pools up to current industry swimming pool design standards. Some of the recommendations provided in this report may be necessary due to other recommendations, or a recommended repair may be appropriate to be provided when another repair is provided.

This report references the “administrative code” which is the Illinois Department of Public Health (IDPH) Administrative Code, Title 77: Public Health, Chapter I: Department of Public Health, Subchapter n: Recreational Facilities, Part 820: Swimming Facility Code. Also referenced is the National Federation of State High School Associations (NFHS) Swimming and Diving Rules.

Hinsdale Central Pool

The Hinsdale Central Pool was constructed in 1958. This pool is a 6-lane, 25-yard competition pool with two 1-meter springboards, and is used for competitive swimming and diving as well as physical education classes. Based upon the original drawings, the pool volume was estimated to be 164,934 gallons. The flow meter indicated a recirculation rate of 500 gpm, yielding a turnover of 5.5 hours. Filtration is provided by two high rate sand filters. Liquid chlorine is used as the pool water sanitizer, and muriatic acid is used as the pH buffer.

The Hinsdale Central pool has been well maintained over the past 58 years. In general, the pool is in good condition and if left as-is, could likely continue to operate for another ten years. However, there are several deficiencies worth noting.

Of all the deficiencies, the main item of note are the clearances provided for springboard diving. While the existing pool shell met these safety requirements at the time of construction, the clearances no longer meet the requirements of NFHS, the governing body for high school swimming and diving competition. A detailed description of these conflicts is given later in this report, along with a drawing highlighting the areas of the pool shell in violation of the requirements.

It has been expressed that the air quality in this facility is a major concern. During the site visit it was noted that the air was of poor quality. The natatorium air quality can be attributed to two main factors: the presence of combined chlorine and an insufficient HVAC system. The HVAC / dehumidification equipment was observed during the site


visit and found to be in poor condition. Medium pressure ultraviolet light (UV) treatment systems have proven to be very effective in the elimination of combined chlorine as well as harmful pathogens (such as cryptosporidium). In addition to improving air quality, the elimination of combined chlorine also helps reduce corrosion of any steel materials in contact with the natatorium air including stainless steel railings, door frames, HVAC equipment and ductwork, and the natatorium building structure.

Given that this facility hosts swimming and diving training and competition, it is important to discuss the functional obsolescence of the natatorium. The perimeter gutter system is not designed to capture waves created during swim competition, which allows them to rebound into the pool and create a turbulent race course. The 6-lanes provided make practices challenging for large teams with both swimmers and divers attempting to use the same space simultaneously. The quantity of spectator seating, as well as the lack of separate warmup lanes prevent this facility from hosting regional or statewide competitions.

The following list summarizes the conditions identified in the report, but should not be considered all inclusive.

Hinsdale Central – Pool Deficiencies

A few locations of cracked and missing tiles were observed within the pool finish.

The tile grout is in need of repair.

The painted tile safety stripe is chipping / fading.

The gutter is operated in a flooded condition.

The gutter trough is not sized to adequately capture waves during swim competition.

The wall inlet spacing is not designed to provide thorough mixing of filtered and treated water into the pool.

The wall inlet design does not meet the industry standard for a competitive pool.

A screw head was observed protruding from one wall inlet, presenting a hazard to swimmers.

The depth markings and warning signs exceed the maximum spacing allowed by the administrative code.

The text provided on the warning signs does not meet the administrative code.

International No Diving symbols are not provided.

Two grab rails are not provided at each egress point.

The existing grab rails are loose.

An ADA pool lift is not provided.


The diving boards do not meet the required clearances for dive competition per the NFHS rules.

The locker rooms are not ADA compliant.

Poor air quality was present in the natatorium.

A leak was observed at one of the gutter dropout pipes. Signs of other leak points were also observed.

Corrosion was observed on the iron piping, pipe hangers and supports, connection hardware, and valves located in the mechanical room.

Corrosion was observed on the recirculation pump.

The filtration rate is slightly in excess of the industry standard.

An air gap is not provided between the backwash piping and the backwash catch basin.

Secondary containment is not provided for the chemical storage containers.

Adequate separation between chemicals is not provided.

The chemical storage tanks are not sealed; vapors are able to escape into the mechanical room.

The surge tank is open to the mechanical room, allowing humidity and chloramines to enter the space.

Hinsdale South Pool

The Hinsdale South Pool was constructed in 1963. This pool is a 6-lane, 25-yard competition pool with two 1-meter springboards, and is used for competitive swimming and diving as well as physical education classes. Based upon the original drawings, the pool volume was estimated to be 171,801 gallons. Filtration is provided by three high rate sand filters. Liquid chlorine is used as the pool water sanitizer, and CO2 is used as the pH buffer.

The Hinsdale South pool has been well maintained over the past 53 years. In general, the pool is in good condition and, similar to Hinsdale Central, it is likely that this pool could continue to operate as-is for another ten years. A list of deficiencies is provided at the end of this summary, but additional commentary is provided for the following items.

Similar to that of Hinsdale Central, the main item of note are the clearances provided for springboard diving. While the pool shell met these safety requirements at the time of construction, the clearances do not meet the requirements of NFHS, the governing body for high school swimming and diving competition. A detailed description of these conflicts is given later in this report, along with a drawing highlighting the areas of the pool shell in violation of the requirements.

Two flow meters are provided, each with a different reading. One indicates 450 gpm, while another indicates 350 gpm. At 450 gpm, the pool turns over every 6.4 hours,


while at 350 gpm the pool turns over every 8.2 hours. In both cases the pool does not meet the 6-hour turnover requirement of the administrative code.

After serving Hinsdale South for the past 53 years, the natatorium has become functionally obsolete. Similar to Hinsdale Central the perimeter gutter system is not designed to capture waves created during swim competition, which allows them to rebound into the pool and create a turbulent race course. The 6-lanes provided make practices challenging for large teams with both swimmers and divers attempting to use the same space simultaneously. The amount of spectator seating provided at this pool is certainly above average. Although, the seats provided at the end of the pool do not offer the best view of swimming or diving competition. Also, the lack of separate warmup lanes makes it challenging for this facility to host regional or statewide competitions.

The following list summarizes the conditions identified in the report, but should not be considered all inclusive.

Hinsdale South – Pool Deficiencies

A few locations of cracked and missing tiles were observed.

The tile grout was observed to need repair.

A safety marking is not provided at a depth of 5 ft. to warn the swimmers of the transition between shallow and deep water, as required by the administrative code.

The gutter system is functionally obsolete, as it cannot capture waves during swim competition.

The main drain cover is broken, which renders it non-compliant with the VGB act and the administrative code.

The wall inlet spacing is not designed to provide thorough mixing of filtered and treated water into the pool.

The wall inlet design does not meet the industry standard for a competitive pool.

The depth markings and warning signs exceed the maximum spacing allowed by the administrative code.

Single poles are provided in lieu of code compliant grab rails at all egress points.

The existing grab rails are loose.

An ADA pool lift is not provided.

The interior side of the underwater light niches display corrosion.

The diving boards do not meet the required clearances for dive competition per the NFHS rules.

The diving boards are in conflict with two of the starting blocks, requiring the boards to be tipped back against the manufacturer’s recommendations.

The locker rooms are not ADA compliant.


Corrosion was observed on the iron piping, pipe hangers and supports, connection hardware, and valves located in the mechanical room.

Corrosion was observed on the recirculation pump, and cast iron fittings.

Two flow meters are provided, each displaying a different reading.

The turnover of the pool exceeds the maximum allowed by the administrative code.

An air gap is not provided at the backwash catch basin.

Secondary containment is not provided for the chemical storage containers.

The chemical storage tanks are not sealed; vapors are able to escape into the mechanical room.

The stainless steel surge tank is corroded.

The surge tank is open to the mechanical room, allowing humidity and chloramines to enter the space.


HINSDALE CENTRAL - GENERAL INFORMATION

Length 75’-2”

Width 42’-0”

Surface Area 3,150 square feet

Perimeter 234 feet

Lanes Six 75’-2” lanes

Water Depth 3’-6 ½” to 10’-0”

Pool Volume 164,934 gallons


HINSDALE CENTRAL - CONDITIONS AND RECOMMENDATIONS


STRUCTURE AND FINISH The pool is approximately 58 years old and is in good condition considering its age. The original tile finish remains and has a few repairs over the years. There were a few locations of cracked and missing tiles observed. The tile grout was observed to need repair. The safety marking at the 5 ft. depth is created by a stripe painted on the tile finish. This paint is chipping and/or fading. No water loss was reported by the staff. Signs of water loss through the pool shell was not observed on the exterior of the pool wall.

Recommendation Re-grout the tile finish. Replace all cracked or missing tiles. Re-paint the safety stripe, or replace this tile with tile of a contrasting color.


PERIMETER OVERFLOW SYSTEM The overflow system is a concrete J-shape gutter with a ceramic tile finish. A total of 16 gutter dropouts are spaced around the perimeter of the pool and connected to a common pipe in the mechanical tunnel. The gutter piping is adequately sized. In pools of this type, the water surface is typically maintained just at the rim of the gutter – this operation is known as rim flow. When rim flow is maintained, tension is created across the water surface which continually draws debris into the gutter. The gutter at the Central pool is maintained in a flooded state, which does not allow debris to be drawn to the gutter. Instead any debris that does reach the gutter trough can quickly be washed back into the pool. A flooded gutter is also not capable of capturing waves created by swimmers, resulting in a more turbulent water surface. The industry standard today is to provide a gutter system with a larger opening and a deeper trough. This enables the system to capture waves created during swim competition and prevent them from rebounding back into the pool.

Recommendation Operate the pool in a rim flow condition, allowing surface debris to be drawn into the gutter trough and removed from the pool.


MAIN DRAINS The main drain is very large, measuring 1 ft x 22 ft. The original main drain grate was replaced with 22 AquaStar anti-entrapment drain covers. The pool has an 8” pipe which connects the main drain to the surge tank. The pipe size is adequate for the flow rate of 500 gpm (observed at the flow meter). The suction piping of the recirculation pump does not have a direct connection to the main drain piping; this adds a layer of safety to the piping design. The two layers of protection – the large anti-entrapment drain and the indirect suction – meets the intent of the VGB Pool and Spa Safety Act which regulates main drains in commercial swimming pools.

Recommendation No recommendation.

POOL INLETS Wall inlets are provided around the perimeter of the pool. A total of 14 inlets are provided, which is adequate to supply the 500 gpm flow rate to the pool. The spacing of the inlets is not uniform and may not provide thorough mixing of the filtered and treated water throughout the pool. It is the current industry standard to provide floor inlets in competition pools due to the influence that wall inlets can have on the race course. At least one wall inlet was observed with a screw head protruding from the surface, which presents a hazard to swimmers.

Recommendation Verify all screws and fasteners are flush with the wall inlets and make necessary repairs.


POOL MARKINGS The original horizontal depth markings are existing. Vertical depth markings were added at a later date. The administrative code requires that depth markings and warning signs be spaced at no more than 25 feet. Multiple markings exceeded this spacing. Markings indicating “No Diving” or the international no diving symbol are required everywhere the water is less than a depth of 5 feet. One marking is provided on either side of the pool stating “Danger – Shallow Water – Do Not Dive.” This marking does not meet the administrative code for a “No Diving” warning sign. Also, the spacing between these two markings is in excess of the 25 ft. maximum.

Recommendation Provide additional depth markings and warning signs to meet the administrative code.

INGRESS AND EGRESS Recessed ladders are provided in the four corners of the pool. Each location has a single grab rail. All grab rails were found to be loose at the time of the site visit. The administrative code requires two grab rails at each location. The grab rails must be securely attached to the pool deck. ADA access is not provided for the pool. Because the perimeter of this pool is less than 300 lineal feet, one primary means of access is required. This would be best provided by a battery operated pool lift. These types of lifts are required where the water depth is less than 48 inches.

Recommendation

Provide new grab rails and anchors. Provide an additional set of grab rails and anchors at each location. Provide an ADA compliant, battery operated pool lift near the shallow end of the pool.


SPRINGBOARD DIVING Two 1-meter springboards are provided. The pool depth below the springboards is 10 feet. While this depth is adequate for the requirements of IDPH, it does not meet the requirements for high school dive competitions, as established by NFHS. The minimum depth allowed for high school competition is 12 ft. Also the 12” ledge provided at the deep end of the pool encroaches on the clear dimension required from the tip of the board back to the pool wall. Please refer to the illustration on the following page.

Recommendation

Remove the diving boards.


SPRINGBOARD DIVING Below is a section view of the pool. The red line indicates the clearance required by the National Federation of State High School Associations. The shaded areas indicate the locations where the Hinsdale Central pool does not meet the required clearances.


Natatorium General Comments: An observation of the locker rooms showed they were not ADA compliant. Multiple curbs exist which would prevent a wheel chair from accessing the space. Also observed was poor air quality in the locker room, especially in the shower area. In this area was a mildew smell, and mold was observed near the bottom of the wall as well as on the ceiling. Air quality in the natatorium is poor. It is suspected that this is caused by a combination of insufficient HVAC equipment and the presence of combined chlorine. The HVAC system will require evaluation by a mechanical engineer to determine its effectiveness. (It was reported at the time of the site visit, that this has taken place and a project to replace the HVAC system is underway.) Combined chlorine can be better controlled by the use of an ultraviolet light (UV) treatment system. Medium pressure UV systems have been very successful at improving the air quality of natatoriums throughout the country. UV systems also eliminate harmful viruses, bacteria and other parasites such as cryptosporidium. Commentary on the existing HVAC equipment is included later in this report with the mechanical equipment.

Recommendation

Renovate the locker rooms to meet the requirements of ADA. Provide a medium pressure UV treatment system. Further evaluate the HVAC/dehumidification systems for the natatorium, locker room, and any other natatorium support spaces.


HINSDALE CENTRAL - MECHANICAL CONDITIONS AND RECOMMENDATIONS


PIPING / VALVES A leak was observed at the piping for one of the gutter drop outs, where the original cast iron piping transitions into PVC. This leak leaves a large puddle on the mechanical room floor. Because the gutters are operated in a flooded condition, the leak is always active. The cast iron at other gutter drop out locations showed a sign of leaking, which is the build-up of calcium and other minerals on the backside of the pool shell and piping. A majority of the pool piping has been replaced with schedule 80 PVC. Corrosion exists on much of this equipment including iron piping, pipe hangers and supports, connection hardware, and valves. However, the piping and valves should be described generally as being in fair condition. Color coded directional arrows are provided on the piping. Valve tags are not provided. Based on a 500 gpm flow rate, the piping is sized adequately. Additional photos of the existing conditions of the piping and valves are shown on the next page.

Recommendation

Repair all leak locations. Replace all corroded piping, hardware, hangers, and supports.



PUMP / MOTOR A single recirculation pump is provided for the pool. Though corrosion was observed on the pump, it appeared to be operating properly. The pump label is corroded and could not be read. Pump information is not given in the original drawings that were provided, therefore the horsepower and flow rate are unknown. The flow rate indicated on the flow meter in the mechanical room is approximately 500 gpm. The original drawings were used to estimate the pool volume, which is approximately 164,934 gallons. At 500 gpm, this pool turns over every 5.7 hours, which meets the requirements of the administrative code. The pump strainer appeared to be in fair good condition, displaying only minor corrosion.

Recommendation Remove corrosion from the recirculation pump and equipment. Re-paint this equipment to prevent further corrosion. Consider replacing the recirculation pump and related equipment with new.


FILTRATION Two steel high rate sand filters are provided, and are in fair condition. No leaks were observed at the filters. Corrosion was minimal. Each filter has a filtration area of 16.5 square feet; the total filtration area is 33 square feet. At a flow rate of 500 gpm, the filtration rate is 15.15 gpm/ft2. This rate is slightly higher than the industry standard of 15 gpm/ft2. An air gap is not provided between the backwash piping and the backwash catch basin. An air gap is required by the administrative code.

Recommendation Modify the backwash piping to provide an air gap. Consider replacing the filtration system to provide a filtration rate less than the 15.0 gpm/ft2 industry standard.


CHEMICAL TREATMENT An Acu-Trol water chemistry controller is provided, which measures ORP and pH. Liquid chlorine (sodium hypochlorite) is used as the sanitizer and muriatic acid is used as the pH buffer. The controller and these chemicals are appropriate for a pool of this type. Single-wall storage tanks are provided for the chemicals and no secondary containment is provided. Should the chlorine and acid tanks rupture, the chemicals will run together due to the slope of the floor. When chlorine and acid are mixed, chlorine gas is formed which is a dangerous material. For this reason, secondary containment is required. The provision of separate storage spaces is the industry standard to help prevent the accidental mixing of chemicals. Neither tank was sealed, except by a shopping bag stuffed into the tank opening. The vapors from both chlorine and acid are corrosive and will corrode the metallic objects in the mechanical room.

Recommendation:

Provide double-wall storage tanks for both chemicals. Provide a separate storage room for the muriatic acid tank, as this is the more corrosive chemical of the two. This storage room should be ventilated to the outdoors. Provide a vapor shield for both storage tanks. Vapor shields are available at Recreonics.com, Item #52-095.


SURGE TANK A surge tank is provided in the mechanical room. The purpose of a surge tank is to store water displaced by swimmers to allow the pool to continue to operate at rim flow. As water spills over the perimeter gutter, it flows by gravity to the surge tank. The surge tank is open to the mechanical room, which allows both humidity and chloramines to enter the air in this space. The administrative code requires 0.6 gallons of surge capacity for every square foot of pool surface area. The industry standard for surge tanks is to provide 1.0 gallons of surge capacity for every square foot of pool surface area. The interior dimensions of the surge tank and normal operating water level are unknown.

Recommendation Provide a lid on the surge tank to prevent humidity and airborne chloramines from escaping the surge tank. Verify the surge capacity compared to the administrative code and the industry standard. Provide additional surge capacity if needed.


MAKE-UP WATER Fresh water is added to the pool via a float valve located in the surge tank. As the normal operating level in the tank is lowered, the valve opens allowing fresh water into the surge tank until the float returns to its normal position. It was not determined during the site visit if an air gap or a backflow preventer is provided on the domestic water line. A water meter is recommended as a means to track the total amount of water added to the pool. If the amount of water added begins to increase, this can serve as a signal that the pool has a hidden leak through buried piping.

Recommendation Verify that backflow prevention is provided for the fresh water fill piping – either by an air gap or by a backflow preventer. Verify if a water meter is provided for the pool.

POOL HEATING No issues were reported regarding the ability to maintain the desired pool temperature. A heat exchanger connected to campus steam heat was observed in the mechanical room. A separate piece of equipment was observed in the mechanical room, which appeared to belong to the heating system as well. This device was observed to be leaking water.

Recommendation

Consult with a mechanical engineer to examine the heating system for the pool and make recommendations.


DEHUMIDIFICATION SYSTEM As noted above, the air in the natatorium was of poor quality and had the familiar “chlorine” smell often associated with pools. This may partly be due to the condition of the HVAC / dehumidification system for the natatorium. The “chlorine” smell is caused by the presence of combined chlorine (also known as chloramines) in the air. As chlorine sanitizes the pool water, it combines with sweat, body oils, etc. to create combined chlorine. Once combined chlorine is formed it has the potential to off-gas into the air, and it is best to eliminate combined chlorine before this happens. Controlling combined chlorine is a process of regular testing of the pool water, super-chlorinating when needed, and also providing supplemental sanitation of the pool water by means of a medium pressure UV treatment system. Medium pressure UV systems have been very successful at improving the air quality of natatoriums throughout the country. UV systems also eliminate harmful viruses, bacteria and other pathogens such as cryptosporidium. UV systems can also help protect the HVAC equipment by preventing corrosive elements out of the air before they reach this air handling equipment. It was stated during the site visit that a project is currently underway to replace the natatorium HVAC system.

Recommendation

Provide a medium pressure UV treatment system for supplemental sanitation and chloramine control.

HINSDALE SOUTH - GENERAL INFORMATION

Length 75’-1 ½”

Width 44’-0”

Surface Area 3,263 square feet

Perimeter 237 feet

Lanes Six 75’-0” lanes, with 9” buffers

Water Depth 3’-6 ½” to 10’-0”

Pool Volume 171,801 gallons


HINSDALE SOUTH - CONDITIONS AND RECOMMENDATIONS


STRUCTURE AND FINISH The pool is approximately 53 years old and is in good condition for its age. The original tile finish remains and has a few repairs over the years. There were a few locations of cracked and missing tiles observed. The tile grout was observed to need repair. A safety marking is not provided at a depth of 5 ft. to warn the swimmers of the transition between shallow and deep water. This marking is required by the administrative code. No water loss was reported by the staff. Signs of water loss through the pool shell was not observed on the exterior of the pool wall.

Recommendation Re-grout the tile finish. Replace all cracked or missing tiles. Provide a tile safety stripe of a contrasting color where the pool depth is 5 ft.


PERIMETER OVERFLOW SYSTEM The overflow system is a concrete J-shape gutter with a ceramic tile finish. A total of 16 gutter dropouts are spaced around the perimeter of the pool and connected to a common pipe in the mechanical tunnel. The gutter piping is adequately sized. The gutter was being operated in a rim flow condition at the time of the site visit. At the time of construction, swimming pool gutters tended to be small and shallow, such as the existing gutter trough. Originally this gutter would have drained directly to waste. Also, as with many pools of this age, when the mechanical equipment was renovated a surge tank was added allowing the water captured by the gutters to be filtered and recirculated through the pool system. Shallow gutters of this type are not able to capture waves created during swim competition. The waves will rebound back into the pool and create a more turbulent water surface, resulting in slower race course. The industry standard today is to provide a gutter system with a larger opening and a deeper trough. This enables the system to capture waves created during swim competition and prevent them from rebounding back into the pool.

Recommendation Because the gutter is being operated as designed, no recommendations are made.


MAIN DRAINS The original main drain was very large, approximately measuring 1 ft x 22 ft. The original main drain grate was covered with PVC paneling and a single anti-entrapment drain cover was placed at the center. The drain cover appears to be the Aegis Anti-Entrapment Shield manufactured by Neptune-Benson. One portion of this drain cover was observed to be broken. This violates the administrative code. The pool has an 8” pipe which connects the main drain to the surge tank. The pipe size is adequate for the flow rate of 450 gpm (observed at the flow meter). The suction piping of the recirculation pump does not have a direct connection to the main drain piping; this adds a layer of safety to the piping design. The two layers of protection – the large anti-entrapment drain and the indirect suction – meets the intent of the VGB Pool and Spa Safety Act which regulates main drains in commercial swimming pools.

Recommendation

Replace the main drain cover.

POOL INLETS Wall inlets are provided around the perimeter of the pool. A total of 14 inlets are provided, which is adequate to supply the 450 gpm flow rate to the pool. The spacing of the inlets is not uniform and may not provide thorough mixing of the filtered and treated water throughout the pool. It is the current industry standard to provide floor inlets in competition pools due to the influence that wall inlets can have on the race course.

Recommendation No recommendation.


POOL MARKINGS The original horizontal depth markings are existing. Vertical depth markings were added at a later date, but not at every location of a horizontal marking. The administrative code requires that depth markings and warning signs be spaced at no more than 25 feet. Multiple markings exceeded this spacing. International No Diving symbols were observed, though the spacing between these markings is greater than the 25 ft. maximum. The shallow end of the pool is indicated to have a depth of 4 feet, however the actual depth was measured to be 3 feet, 6 inches.

Recommendation Provide additional depth markings and warning signs to meet the administrative code. Update existing depth markings to indicate the accurate pool depth.

INGRESS AND EGRESS Recessed ladders are provided in the four corners of the pool, as well as two located at the mid-point on either side. Instead of a grab rail, each location has a single vertical pole. Each of these poles were found to be loose at the time of the site visit. The administrative code requires two grab rails at each location. The grab rails must be securely attached to the pool deck. ADA access is not provided for the pool. Because the perimeter of this pool is less than 300 lineal feet, one primary means of access is required. This would be best provided by a battery operated pool lift. These types of lifts are required where the water depth is less than 48 inches.

Recommendation Provide two new grab rails and anchors at each ladder location. Provide an ADA compliant, battery operated pool lift near the shallow end of the pool.


UNDERWATER LIGHTS A total of 16 underwater lights are provided around the perimeter of the pool. These were observed to be functional at the time of the site visit. An observation of the light niches from the mechanical room showed several to be corroded.

Recommendation Clean corrosion from underwater light niches where needed.


SPRINGBOARD DIVING Two 1-meter springboards are provided. The pool depth below the springboards is 10 feet. While this depth is adequate for the requirements of IDPH, it does not meet the requirements for high school dive competitions, as established by NFHS. The minimum depth allowed for high school competition is 12 ft. Also the 12” ledge provided at the deep end of the pool encroaches on the clear dimension required from the tip of the board back to the pool wall. Please refer to the illustration on the following page. Originally, the starting blocks would have been installed at the shallow end of this pool. This was very common in the era in which this pool was built. When the starting blocks were relocated to the deep end of the pool, it was necessary to install two of the blocks directly in front of the diving board support pedestal. This can make accessing the starting block a little awkward. More importantly, this requires the diving boards to be tipped back against the natatorium wall whenever the starting blocks are in use. Tipping back the diving boards is against the manufacturer’s recommendations.

Recommendation

Due to the conflict with the required clearances, removal of the diving boards is recommended.


SPRINGBOARD DIVING Below is a section view of the pool. The red line indicates the clearance required by the National Federation of State High School Associations. The shaded areas indicate the locations where the Hinsdale South pool does not meet the required clearances.


Natatorium General Comments: An observation of the locker rooms showed they were not ADA compliant. Multiple curbs exist which would prevent a wheel chair from accessing the space. While the air quality in the natatorium was better than that at Central, there was a noticeable chloramine smell. is poor. It was reported during the site visit that the HVAC / dehumidification system for the natatorium was replaced in 2012. Combined chlorine can be better controlled by the use of an ultraviolet light (UV) treatment system. Medium pressure UV systems have become an industry standard for indoor swimming pools. These systems improve air quality by eliminating combined chlorine in the pool water. UV systems also eliminate harmful viruses, bacteria and other parasites such as cryptosporidium.

Recommendation Renovate the locker rooms to meet the requirements of ADA. Provide a medium pressure UV treatment system.


HINSDALE SOUTH - MECHANICAL CONDITIONS AND RECOMMENDATIONS


PIPING / VALVES The original piping has been replaced with PVC. No active leaks were observed from the pool piping. The back side of the pool shell is painted. There were a few locations where this paint was peeled, along with mineral deposits, indicating a leak may have existed in these locations in the past. Corrosion exists on much of this equipment including iron piping, pipe hangers and supports, connection hardware, and valves. However, the piping and valves should be described generally as being in fair condition. Color coded directional arrows are provided on the piping. Valve tags are not provided. Based on a 450 gpm flow rate, the piping is sized adequately.

Recommendation Replace all corroded piping, hardware, hangers, and supports.


PUMP / MOTOR A single recirculation pump is provided for the pool. Though corrosion was observed on the pump, it appeared to be operating properly. The pump strainer appeared to be in fair good condition, displaying only minor corrosion. Cast iron reducer fittings at the pump are also corroded. The pump label is corroded and could not be read. Pump information is not given in the original drawings that were provided, therefore the horsepower and flow rate are unknown. Two flow meters were observed in the mechanical room. One indicated a flow rate of 350 gpm, the other a flow rate of 450 gpm. The original drawings were used to estimate the pool volume, which is approximately 171,801 gallons. At 450 gpm, this pool turns over every 6.4 hours, which does not meet the current requirements of the administrative code. If the 350 gpm flow rate is accurate, the turnover of the pool extends further to 8.2 hours.

Recommendation

Remove corrosion from the recirculation pump and equipment. Re-paint this equipment to prevent further corrosion. Verify the actual flow rate of the pool. Consider providing a new flow meter to accomplish this task. Provide a minimum flow rate of 6 hours. This may be possible by replacing the impeller in the existing pump. Consider replacing the recirculation pump and related equipment with new.


FILTRATION Three steel high rate sand filters are provided, and are in fair condition. No leaks were observed at the filters. The feet of the filter tanks were observed to be corroded. Each filter has a filtration area of 10.67 square feet; the total filtration area is 32 square feet. At a flow rate of 450 gpm, the filtration rate is 10.93 gpm/ft2. This rate is below the industry standard of 15 gpm/ft2. The automatic air relief valve on one of the filters was observed to be corroded. An air gap is not provided between the backwash piping and the backwash catch basin. An air gap is required by the administrative code.

Recommendation

Modify the backwash piping to provide an air gap. Verify the functionality of the corroded air relief valve. Replace valve if necessary. Prepare and paint the filter feet to help slow the corrosion process.


CHEMICAL TREATMENT A relatively new Prominent water chemistry controller is provided. This controller measures ORP and pH, in addition to ppm and temperature, and can provide additional features such as remote access. Liquid chlorine (sodium hypochlorite) is used as the sanitizer and CO2 is used as the pH buffer. The controller and these chemicals are appropriate for a pool of this type. Single-wall storage tanks are provided for liquid chlorine and no secondary containment is provided. The chorine tank is not sealed and vapors are able to escape into the mechanical room. Chlorine vapors are corrosive and will lead to corrosion on the metal objects in the mechanical room.

Recommendation: Provide a double-wall storage tank for liquid chlorine. Provide a vapor shield for the chlorine storage tank. Vapor shields are available at Recreonics.com, Item #52-095.


SURGE TANK A surge tank is provided in the mechanical room. The purpose of a surge tank is to store water displaced by swimmers to allow the pool to continue to operate at rim flow. As water spills over the perimeter gutter, it flows by gravity to the surge tank. The surge tank is open to the mechanical room, which allows both humidity and chloramines to enter the air in this space. The administrative code requires 0.6 gallons of surge capacity for every square foot of pool surface area. The industry standard for surge tanks is to provide 1.0 gallons of surge capacity for every square foot of pool surface area. The interior dimensions of the surge tank and normal operating water level are unknown. The surge tank is made of stainless steel and is displaying significant corrosion. Removing the corrosion and painting the surface with an epoxy paint may increase its lifespan.

Recommendation

Provide a lid on the surge tank to prevent humidity and airborne chloramines from escaping the surge tank. Verify the surge capacity compared to the administrative code and the industry standard. Provide additional surge capacity if needed. Prepare and paint the stainless steel.


MAKE-UP WATER Fresh water is added to the pool via a float valve located in the surge tank. As the normal operating level in the tank is lowered, the valve opens allowing fresh water into the surge tank until the float returns to its normal position. A second float valve is provided on a smaller domestic water line. It is unknown why to separate make-up systems are provided. An air gap is provided between the top of the surge tank and the larger of the two make-up systems. The smaller water line extends below the top of the surge tank. It is unknown if a backflow preventer is provided elsewhere for this line. A water meter is recommended as a means to track the total amount of water added to the pool. If the amount of water added begins to increase, this can serve as a signal that the pool has a hidden leak through buried piping.

Recommendation

Verify that backflow prevention is provided for the smaller of the two domestic water lines. Verify if a water meter is provided for the pool.

POOL HEATING No issues were reported regarding the ability to maintain the desired pool temperature. Bypass piping to the heat exchanger was observed in the mechanical room.

Recommendation Consult with a mechanical engineer to examine the heating system for the pool and make recommendations.


OPINION OF PROBABLE CONSTRUCTION COST

The following spreadsheet provides the Opinion of Probable Construction Cost to repair the pools for the long term recommendations described in the report that are directly related to the pool system. The opinion of probable construction cost does not include architectural and engineering design fees or inflation until the items are addressed.

Opinion of Probable Construction Cost

Hinsdale Central High School

Opinion of Probable Cost

Item Cost

1 Miscellaneous tile repair, re-grout tile finish, provide tile safety stripe $75,000

2 Provide additional depth markings and warning signs $5,000

3 Provide new grab rails and anchors (4 locations) $12,000

4 Provide an ADA complaint, battery operated pool lift $6,500

5 Remove the diving boards $2,500

6 Provide a medium pressure UV treatment system $55,000

7 Miscellaneous piping repair and replacement $3,500

8 Provide new recirculation pump and related equipment $7,500

9 Provide double-wall chemical storage tanks, vapor shields, and separation of chemicals $15,000

10 Provide a surge tank lid $1,500

Pool Repairs Subtotal $183,500

20% Contingency $36,700

Total (2016 USD) $220,200

11 Add depth to the pool to permit use of 1-meter springboards $250,000

12 Renovate all mechanical equipment $175,000

13 New tile and grout $275,000



Total (2016 USD) $840,000

14 Verify screws and fasteners are flush with the pool wall

15 Provide an air gap at the backwash catch basin

16 Verify surge capacity provided in surge tank

Pool Repair Items

POOL REPAIRS

ITEMS PERFORMED BY STAFF

LONG-TERM CONSIDERATIONS


Hinsdale South High School

Opinion of Probable Cost

Item Cost

1 Miscellaneous tile repair, re-grout tile finish, provide tile safety stripe $75,000

2 Provide additional depth markings and warning signs $5,000

3 Provide new grab rails and anchors (6 locations) $18,000

4 Provide an ADA complaint, battery operated pool lift $6,500

5 Remove the diving boards $2,500

6 Provide a new VGB compliant main drain cover $3,500

7 Provide a medium pressure UV treatment system $55,000

8 Miscellaneous piping repair and replacement $3,500

9 Provide new recirculation pump and related equipment $7,500

10 Provide new flow meter and flow sensor $4,000

11 Provide double-wall chlorine storage tank and vapor shield $7,500

12 Provide a surge tank lid $1,500

13 Prepare and paint stainless steel surge tank $10,000



Total (2016 USD) $239,400

14 Add depth to the pool to permit use of 1-meter springboards $250,000

15 Renovate all mechanical equipment $175,000

16 New tile and grout $275,000

Pool Repairs Subtotal $700,00020% Contingency $140,000

Total (2016 USD) $840,000

17 Clean corrosion from underwater light niche

18 Provide an air gap at the backwash catch basin

19 Verify functionality of the corroded automatic air relief valve

20 Prepare and paint the feet of the filter tank

21 Verify surge capacity provided in surge tank

ITEMS PERFORMED BY STAFF

Pool Repair Items

POOL REPAIRS

LONG-TERM CONSIDERATIONS

The opinions of probable construction cost are based on current 2016 prices. This report is based on information that was current as of November, 2016. The preceding opinion of probable costs estimates are based upon a protocol in which a general contractor or swimming pool contractor executes all of the tasks with its own labor and that of qualified subcontractors.


It is recognized that the Consultant or Owner have no control over the cost of labor, materials or equipment, over the Contractor’s methods of determining bid prices, or over competitive bidding, market or negotiating conditions. Accordingly, the Consultant cannot, and does not, warrant or represent that bids or negotiated prices will not vary from the Owner’s project budget or from any opinion of construction cost or evaluation prepared or agreed to by the Consultant.

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HINSDALE SCHOOL DISTRICT SWIMMING POOL AUDIT€¦ · general, the pool is in good condition and if...

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