Pinellas Park Water Management
30 years of goals and accomplishments
In the 1950s, paper carriers in Pinellas Park, FL, had a unique way
of dealing with the city’s severe flooding problems. On rainy days, the
carriers wrapped their newspapers in waxed paper bags. This kept the
papers dry and enabled them to float, ideally long enough for residents
to retrieve them. Eventually, though, the waxed paper became saturated
and the papers sank in the standing water.
The Pinellas Park area has experienced relentless flooding for
decades. The low-lying area has the Gulf of Mexico a short distance to
the west and Tampa Bay to the east. Pinellas County, in which Pinellas
Park is located, averages 52 inches of rainfall each year, with the
majority of rain occurring in a four-month period. During wet weather,
the groundwater table rises nearly to the surface, causing the area to
flood during even the smallest rain events.
Harry Marlow, PLS, a retired land surveyor who has lived in Pinellas
Park since 1956, recalls seeing children paddle up his street in canoes
after thunderstorms. “My office was about 1 mile from my house, and I
can remember it taking me 45 minutes to get home because of the water,”
Weary of the flooding, in 1975 the citizens of the Pinellas Park area
asked the Florida State Legislature for help. The legislature
recommended creating a special district dedicated to stormwater
management. That same year voters agreed, by a 2.5:1 ratio, to tax
themselves up to 3 mills ($3 for every $1,000 of assessed property
value) to create a State of Florida special water management district
called the Pinellas Park Water Management District (PPWMD).
The PPWMD had one primary goal: to alleviate flooding by retaining
the runoff from 25-year/24-hour recurring storm events within channel
banks and 100-year/24-hour storm events out of houses. Today, after 30
years in operation, the district is only a few projects away from
meeting that goal.
The design criteria established at the district’s inception were
fine-tuned in 1992 and currently dictate the basis of drainage
improvement designs. They are as follows:
- Contain the 25-year flood event within the channel banks with 1 foot of freeboard where possible.
- Minimize head losses at culverts and bridge crossings to maintain clearance above the 25-year flood event.
- Provide adequate capacity within the primary drainage system to be
consistent with a 10-year storm event design capacity in the secondary
- Limit flooding during a 100-year flood event to streets and yards if possible.
|Before: Channel 3 looking east from 35th Street North
|After: Channel 3 looking east from 35th Street North, concrete lined
District Plans, Builds, Manages, and Maintains Infrastructure
The PPWMD is responsible for managing the primary stormwater drainage
system in its approximately 15-square-mile jurisdictional area, which
encompasses the city of Pinellas Park and unincorporated Pinellas
County. The secondary systems, including street drainage, curb and
gutter inlets, and associated conveyance systems, are maintained by the
city and county.
The district is governed by a board of directors appointed by the
City of Pinellas Park City Council and the Pinellas County Board of
County Commissioners. The work of the PPWMD is carried out by the
executive director, a staff of administrative and maintenance
professionals, and consultants.
Irrigation Ditches Converted to Drainage Basins
The PPWMD area began as an agricultural community recognized for its
flower farms. Local farmers also raised dairy cattle and harvested
sugar cane and vegetables. Around 1915, many ditches, including five
major ditches that are still in use today, were built to irrigate
The area was hit hard by the Great Depression of the 1930s. The
economy floundered, and many of the 2,000 residents left to pursue work
elsewhere. Development along south-central Florida’s roads, combined
with the growth of nearby St. Petersburg, helped bring the area and the
city of Pinellas Park, in particular, back to life. By 1960, more than
11,000 people called the area home, and as of April 1, 2006, the
population was estimated at 48,835. The city is 16.09 square miles,
based on annexation data collected from 1950 through June 2003. Because
of voluntary annexations, the city’s physical size is continually
From the beginning, the PPWMD recognized that the five ditches would
serve as the backbone of its stormwater management program. As capital
improvements progressed, the ditches, configured as a system of
channels, began functioning as drainage basins. Based on this, the PPWMD
was divided into five primary service areas, described as follows:
- The Channel 1 Basin flows westerly to its outfall at the
Cross Bayou Canal. The conveyance system is composed of concrete-paved
and concrete-filled fabric-lined channels, grass-lined reinforced
earthen channels, bridges, culverts, unimproved channels, and pipe
systems. The channels total approximately 9.3 miles in length, with
bottom widths ranging from 2 to 26 feet.
- The Channel 2 system comprises a main channel and four
tributary channels that provide drainage for approximately 2,270 acres.
Channel 2 serves as the major outfall for a city-maintained storm sewer,
as do all the other channels. The general flow is easterly, and the 6
miles of channels, bridges, culverts, and pipe sections discharge to
- Drainage in the southeastern boundary of the PPWMD occurs within the Channel 3 Basin,
which also discharges to Sawgrass Lake. The channels in Basin 3 total
2.8 miles in length and include piped sections, bridges, and
concrete-paved and unimproved channels.
- Located in the southwestern portion of the PPWMD is the Channel 4 Basin.
It includes a main channel, three minor tributaries, and a lake. The
basin drains approximately 1,857 acres and flows southwesterly to its
confluence with Joe’s Creek. The channels measure 4.7 miles in length.
- The Channel 5 Basin is a 560-acre drainage area in the
central portion of the district’s jurisdiction. The system, which flows
southwesterly to its outfall at Joe’s Creek, consists of unimproved
channels, concrete-paved channels, articulating block–paved channels,
bridges, culverts, a piped storm sewer system, and other piped sections
measuring approximately 1.4 miles in length.
First Projects Help Open Water Flow
The first few years of the PPWMD’s existence were spent developing
master plans for each drainage basin. These were updated in the 1990s
and are still in use today. Directing the efforts was the district’s
first executive director, Morton S. Lipschultz, P.E. Lipschultz was a
Pinellas Park resident who had worked with the city as a consulting
engineer in private practice. He was instrumental in the district’s
establishment and served as executive director until 1995. Through his
knowledge of civil engineering, Lipschultz represented the technical
side of the PPWMD’s creation and justified how the area’s flooding
problems could be addressed. The political components of the district’s
endeavors were spearheaded by some long-established residents and
community champions, including Loyd Tingler and Joe Wornicki.
|The Loyd Tingler Nature Park features recreational amenities while
accommodating water storage and addressing water-quality issues.
|The recirculating drawdown pump station at the park
The PPWMD’s first engineering consultant was Greiner Engineering
Sciences Inc. (now URS Corp.). In 1979 construction began on the
district’s first project—a concrete-lined channel in the Channel 1
Basin. On May 9, 1979, a slow-moving, low-pressure storm dumped between
10 and 16 inches of rain across Pinellas County and caused severe
flooding in Pinellas Park. Cars were submerged to their rooftops.
Hundreds of homes and businesses were flooded. One resident recalls
walking home in water almost to his shoulders. Obviously, the work of
the PPWMD had not started a moment too soon.
The early projects focused on the downstream ends of the five basins.
Concrete-lined channels and concrete-filled fabric-lined sediment traps
and embankment erosion protection were installed to prevent erosion,
decrease hydraulic friction, and reduce maintenance. Where possible, the
projects typically widened and deepened the channels to maximize
conveyance to the outfalls and to increase storage. This helped move the
stormwater more effectively from the drainage basins and residential
neighborhoods. Each year, the PPWMD completed three or four more
projects, gradually fulfilling its master plan recommendations and its
ultimate goal of alleviating flooding in the Pinellas Park area.
In 1990, CDM became the district’s general engineering consultant to
oversee design and construction of multiple drainage improvement
projects. In 2003, the engineering firms of McKim & Creed, TBE
Group, and Advanced Engineering & Design were also selected to
assist the district. Together, these firms are helping the PPWMD
complete its final projects.
Paradise in Concrete
Originally, all concrete-lined channels included concrete bottoms.
However, with the ever-increasing focus to refine water-quality
standards, the Southwest Florida Water Management District (SWFWMD)
expressed concern that the concrete-lined bottoms would negatively
impact existing wildlife habitats and water quality. To address this,
and to provide the stormwater with more contact with natural ground, an
alternate design was proposed. The PPWMD and its engineers redesigned
most channels to incorporate a natural bottom with concrete sides. The
earth bottom created an attractive environment for grasses and other
vegetation, while the reinforced concrete sideslopes stabilized the
embankments, prevented erosion, and virtually eliminated slope
To support the mostly 1.5-foot-horizontal to 1.0-foot-vertical
sideslopes of the reinforced concrete-lined channels, engineers
developed a reinforced concrete strut design connected to the
sideslope’s reinforced concrete footers.
Whether the channels were constructed with concrete bottoms or
open/natural bottoms, habitats and ecosystems prevail. The
concrete-lined bottoms capture sediment, which allows wetland plants to
grow and encourages wildlife to inhabit the space in search of food.
These drainage channels are home to fish and crabs in the downstream
tidal areas. Egrets, herons, ducks, anhinga, and osprey populate areas
surrounding the channels because of the consistent food source.
Occasionally, an alligator, water moccasin, copperhead, or otter is
Volunteers Help Build Park Amenities
In 1992, the PPWMD completed one of its most ambitious projects: the
Loyd Tingler Nature Park. Originally, the project was defined as a
water-quality and flood control facility, but through the actions of
Lipschultz and the community, it evolved into a city park that fulfills
its original purpose and provides a recreational amenity.
|The sediment pond is shown in the foreground of this photograph,
with the littoral area in the background and to the left.
The park was originally the vision of the Florida Department of
Environmental Regulation (DER) and the PPWMD Board of Directors. Through
hydrologic and hydraulic modeling, it was determined that stormwater
storage would be required to reduce flooding in the Channel 1 Basin. The
Florida DER proposed that an offline facility directly connected to
Channel 1 be designed to provide storage and to reduce flooding. In
addition, the facility would serve as a water-quality enhancement area
to mitigate the perceived loss of habitat and runoff treatment because
of the recommended concrete lining of Channel 1. Through stormwater
analysis, the PPWMD’s consultant determined that the concentration of
nutrients and metals was greater in tributary Channel 1C than in the
main Channel 1. Therefore, the design diverted Channel 1C instead of the
main channel. This allowed normal flow to enter the facility via a
diversion weir. The weir was designed to divert flow up to the
25-year/24-hour recurring storm event through one 54-inch circular
reinforced concrete pipe.
The facility was designed to be an offline retention and
sedimentation pond. Flow—under normal conditions and up to the 25-year
event—conveys sediment that settles in a pond. The flow then continues
to a shallow, littoral area containing native Florida wetland and upland
plants and trees selected for maximum nutrient uptake and then to an
outfall structure with a bleed-down orifice to Channel 1.
The facility also features a pump station containing two
650-gallon-per-minute pumps. The valving configuration at the station
allows the PPWMD to lower the pond volume and discharge to the adjacent
concrete Channel 1 if a major storm event is approaching. The dual-use
pump station normally operates with a timer to recirculate the pond
water, thereby preventing the lake water from becoming stagnant.
While the original purpose of the facility was to serve as a flood
control and water-quality improvement area, it didn’t take long for the
PPWMD and the community to realize that the site could provide
additional benefits not only to the environment but to the community as
well. The result is a 6.4-acre park and nature area that features a lake
with cypress trees, pine, Florida native wetland plants, a gazebo, a
boardwalk, a picnic area, and an equestrian trail.
|Lake Boisvert is an offline water storage facility
that has reduced flooding in Pinellas Park.
|An aerial view of Loyd Tingler Nature Park
It was brought to fruition through the help of volunteers from the
local community. Members of the Pinellas Park Kiwanis Club helped lead
the volunteer effort. The local chapter of the Florida Engineering
Society donated the engineering design. A contractor developed the
construction plan free of charge.
The park was named for the late Loyd Tingler, who served on the
PPWMD’s Board of Directors from 1975 though 1987 and was instrumental in
making the PPWMD a reality. In 2000, ownership of the Loyd Tingler
Nature Park was transferred from the PPWMD to the City of Pinellas Park.
Innovative Lake Design Offers Offline Stormwater Storage
While many areas in Pinellas Park were infamous for flooding, the
Channel 3 Basin was especially notorious for overflowing into nearby
neighborhoods and, specifically, the Fortuna Park subdivision. Analysis,
modeling, and other assessments helped engineers determine that water
storage for this drainage basin was necessary in the upstream portion of
the watershed. Unfortunately, the surrounding area was almost
completely developed and offered very little land available for offline
The PPWMD investigated several areas, including a public soccer
field, a small forested area, and a piece of property that was home to
the district’s new headquarters. The PPWMD had recently relocated its
offices to this parcel, and hydrologic and hydraulic analyses indicated
that the district’s property was the optimal location for the
much-needed water storage facility. Ever faithful to its mission of
alleviating flooding in Pinellas Park, the district made the land
available for the design and construction of Lake Boisvert.
Named for former board member Andrew Boisvert, the lake was designed
as an offline stormwater storage facility that would help store a
significant volume. Because of Lake Boisvert and street drainage
improvements made concurrently by the city, the flood stages were
lowered in the surrounding area and, in particular, Fortuna Park. This
project became an essential element in the overall Channel 3 master
As runoff enters Channel 3, the water rises in the main channel and
then drains into Lake Boisvert before overflowing the channel banks.
This additional storage, as well as the wider, deeper concrete lining of
Channel 3, has measurably reduced street flooding to the surrounding
The additional storage provided by the offline Lake Boisvert was
created not only by the construction of the lake itself but also by the
way in which its volume and function are maximized, even in a
constrained size and location. To create more available storage volume,
the lake is artificially kept low by draining it to a depth below the
surrounding normal water table. This is done by installing a discharge
pipe with a backflow prevention flapper valve that keeps the lake at
this low elevation and continuously drains the lake to the level of
Channel 3. A concrete weir separates the lake from the tributary
connected to the main channel, Channel 3. The discharge pipe penetrates
the concrete weir.
Permitting for this project proved difficult but not impossible. The
permitting authority, the SWFWMD, was concerned that by artificially
lowering the normal water table, surrounding structures, primarily light
industrial in nature, could be affected. To acquire the permit,
groundwater modeling was performed, which indicated no impact to these
structures. Channel 3 was concrete-lined from Fortuna Park to the
entrance to Sawgrass Lake. Two inline widened areas upstream of US 19
were installed on land purchased from a local electric utility, Florida
Power Corp. (Progress Energy).
A Project Put to the Ultimate Test
On February 3, 2006, the skies opened up over west-central Florida,
dumping 9 inches of rain in three hours and a total of 11.35 inches of
rain in 24 hours. Roadways became lakes. Roofs collapsed. People were
stranded as water flowed into their cars. Everything flooded … almost.
The final upstream project in the PPWMD’s Channel 1 Basin—a
concrete-lined drainage channel and culvert system—worked in conjunction
with other downstream improvements to keep areas of the city functional
and drivable during the record-setting deluge.
The $1.6 million system, designed by McKim & Creed, replaced an
open vegetated ditch with 1,100 feet of concrete lining featuring an
open, natural bottom. A roadside drainage ditch plagued by erosion was
converted to 650 feet of box culvert below a neat grass catchment area.
Put to its first major test, the system performed better than
expected. Water rushed through the culvert instead of the streets. Two
intersections close to the project held 3 to 4 inches of standing water
for a few hours, rather than days. The roads were easily passable, and
no houses in the area were flooded.
Maintaining the Infrastructure
The PPWMD is responsible not only for building the stormwater
management infrastructure but also for maintaining it. To accomplish
this, the district employs 12 people, including an executive director,
administrative and support professionals, and maintenance specialists.
|Before: Channel 3 looking east toward 35th Street North
|After: Channel 3 looking east toward 35th Street North
In some areas, the channels traverse residents’ yards, so the
channels must be kept clean, functional, and kempt. The channels are
mowed twice each year during the growing season. Blockages, which can
include everything from storm debris to couches and chairs, are removed
as needed to keep the stormwater flowing. Sediment traps in the channel
bottoms are routinely cleaned to prevent obstruction. Most of the
channels contain weep holes, which are cleaned regularly to prevent
groundwater pressure from building up behind the concrete walls.
Because some of the channels are as wide as 26 feet, a variety of
equipment is required to keep them maintained. The district has two
Spyder excavators that can excavate, trim, and mow, with the ability to
infiltrate places humans cannot. Also included in the arsenal of
maintenance equipment are a variety of mowers, a front-end loader, four
dump trucks, sprayer equipment, emergency pumps, and a boat.
Knowing the Past Helps Determine the Future
In the 1990s, the district installed rain gauges and level recorders
so it could record rainfall, maintenance activities, and the water
level in each of the channel basins. Monthly reports are produced, and
the information is incorporated into the PPWMD’s geographic information
system. An annual report summarizes the previous year’s rainfall and
maintenance activities and outlines projects to be completed in the
Since the district was established, flooding in the Pinellas Park
area has decreased sufficiently for the district to apply for a Letter
of Map Revision to the Federal Emergency Management Agency. If accepted
and revised, updated Federal Insurance Rate Maps (FIRMs) will reduce the
100-year flood zones as defined by the FIRMs. Homeowners’ flood
insurance requirements will be eliminated because of the proven and
observed reduction in flooding.
The city has grown and benefited significantly as
developers, now confident that new communities will not be plagued by
flooding, have built new neighborhoods. “The district has done a
tremendous amount of good,” says Marlow. “People were afraid that if
they built here, their homes would flood. Now people are coming here in
droves. It took a lot of hard work on the part of people in the 1970s to
get this district set up and approved.”
The PPWMD anticipates completing its originally identified projects
in 2009. At that time its goal—to alleviate flooding in the Pinellas
Park area by keeping 25-year storms within channel banks and 100-year
storm events out of houses—will be accomplished. As the PPWMD works to
complete its mission, it has found that recent additional higher-density
land uses are increasing the amount of runoff, and additional projects
are being evaluated to accommodate the increased flows. Maintenance
repairs and rebuilding due to wear and useful structure life failure are
also being identified and will be addressed in the near future.
Author's Bio: Daniel E. Glaser, P.E., is an associate with McKim & Creed and manages stormwater engineering in the firm’s Clearwater, FL, office.
Author's Bio: Richard O. Fraze, P.E., is the executive director of the Pinellas Park Water Management District and served on the Board of Directors from 1984 to 2006.