§ 110-50. Technical specifications for installation.

The installations must be in compliance with the following specifications:

Location of property corners and water/wastewater service lines. Prior to issuance of a right-of-way use permit for swale enclosure, the property owner's contractor will locate the front lot property corner markers and the water and wastewater service lines. The county water and wastewater departments shall be requested to mark the approximate line locations on the ground surface and the owner's contractor shall carefully uncover the lines to check for elevation conflicts with the proposed swale modifications. The right-of-way use permit application shall include this information. If a conflict occurs, the application shall contain adequate drawings and written statements to provide for a proper resolution of the conflict(s), including the possibilities of lowering/raising the utility service line(s) by the county water and wastewater departments staff. All costs to raise or lower the county utility service lines will be borne by the permittee.

Trenching. Excavation of the existing swale to accommodate the proposed underlain pipe and rock trench shall extend to provide a minimum of one foot of rock on both sides of the pipe, six inches on the top and bottom of the pipe, and six inches of soil backfill over top of the rock trench. During the course of the construction activities, excavated material shall be placed in such a manner as to not restrict traffic movements along the street or avenue.

Geotextile installation. A nonwoven geotextile fabric with a minimum weight of 4 ounces per square yard (e.g. Mirafi NL140, Typar 3401, Synthetic Industries P0451, etc.) shall be placed in the excavated trench to separate the rock trench from the surrounding soil. Sufficient fabric shall be provided to allow for a one foot overlap at all seams. A second layer of fabric shall be wrapped directly around the pipe with a minimum one-foot overlap at all seams.

Rock trench installation. The rock trench shall be constructed using a washed, Florida Department of Transportation certified No. 57 stone. The stone shall be wrapped by the outer layer of geotextile fabric and shall extend a minimum of one foot of rock on both sides of the pipe and six inches on the top and bottom of the pipe.

Placement of pipe. After the bottom six inch thickness of rock trench is placed, the inner layer of fabric shall be placed in the trench and the pipe laid to proper grade. All pipe connections shall be secure and the inner layer of fabric wrapped completely around the pipe with a minimum one foot overlap at all seams. Placement of the rock trench around the sides and over the top of the pipe shall be performed with due care to prevent the movement of the pipe. For pipe utilizing bell and spigot connections, the bell shall be laid in the upstream direction of flow.

Placement of risers. Twelve inch diameter minimum risers shall be installed to allow the shallow swale to discharge into the underlying pipe. The recommended configuration utilizes a manufactured "T" section but the use of Florida Department of Transportation type "C" catch basins are also acceptable when a manufactured "T" section is not available or the owner prefers the catch basin installation. The top of the riser shall extend six inches above the bottom of the swale. A cast iron slotted grate shall be installed at the top of the riser. Where reinforced concrete pipe is used, the grate shall be placed in the pipe bell. Where other pipe materials are used, the grate shall be placed in a reinforced precast concrete collar sized to fit the grate and pipe material. Minimum dimensions for the reinforced precast collar are six-inch thickness and 24-inch outside diameter (or 24-inch square outside dimension). The precast collar will be mudded to the riser pipe and placed on compacted backfill material. Where neighbors enclose the swale, only one riser needs to be installed for each segment of regraded shallow swale.

Placement of end berm. When the neighboring property utilizes an open swale system instead of an enclosed swale system, an end berm shall be constructed to separate the new regraded shallow swale from the adjoining open swale. The purpose is to force all of the water from the regraded shallow swale to drain into the riser inlet and into the underlying perforated pipe. The top elevation of the end berm will be six inches higher than the riser inlet.

End treatment of pipe. When the neighboring property utilizes an open swale system instead of an enclosed swale system, a mitered end section with concrete collar shall be required at the end of the pipe (unless the county's right-of-way permit review determines the location is not appropriate and deletes this mitered end section requirement) and the neighbor's swale bottom shall be regraded (maximum bottom slope of 4 horizontal to 1 vertical) to connect to the installed perforated pipe invert (bottom inside elevation). When the neighboring property utilizes an enclosed swale system, and either the pipes are different materials or invert elevations do not match, a Florida Department of Transportation type "C" catch basin shall be utilized to make the connection. This type "C" catch basin will also function as the riser inlet. When the neighboring property utilizes an enclosed swale system, and the pipe materials and invert elevations match, the pipes shall be connected directly.

Backfilling and regrading of shallow swale. Upon proper placement of the pipe within the rock trench, the nonwoven geotextile fabric shall be overlapped a minimum of one foot across the top of the rock and backfill sandy soil material placed a minimum of six inches beneath the bottom of the shallow swale and regraded to the proper longitudinal and side slopes. Maximum side slopes for the shallow (14″ deep) regraded swale are 3 horizontal to 1 vertical. The longitudinal slope of the swale shall be directed toward the riser inlet(s). When a reinforced concrete collar is used to secure the grate to the riser, the backfill material shall be thoroughly compacted to prevent settlement and ensure that the collar can support any weight placed on the grate.

Sodding and placement of sprinklers. Upon completion of regrading, the disturbed areas shall be sodded with the same type sod as the remainder of the yard, with the exception that where floratam sod is proposed, the owner must provide for adequate sprinklers to keep the sod alive. Finished elevations must not project above the edge of pavement and shall be in conformance with the detail drawing prepared by Agnoli, Barber and Brundage, Inc. attached as Exhibit "A"*. Sprinklers shall not be installed within the right-of-way. Any sprinkler installations shall be on the owners property and shall utilize spray heads that can cast water across the width of the swale.

(Ord. No. 98-1, § 10)

Note— *Exhibit "A" is not set out herein but is available for inspection in the offices of the county clerk.