§ 6.05.04. Stormwater management requirements.

(a)

Performance standards. All development must be designed, constructed and maintained to meet the following performance standards:

(1)

While development activity is underway and after it is completed, the characteristics of stormwater runoff shall approximate the rate, volume, quality and timing of stormwater runoff that occurred under the site's natural unimproved or existing state, except that the first inch of rainfall shall be retained on site and no discharge shall exceed the predevelopment pollutant level or runoff rate from the property.

(2)

Stormwater as a result of a 25-year, 24-hour storm shall be retained on the property and any excess filtered prior to release. No discharge shall exceed the predeveloped runoff.

(3)

So as to preclude pollution of the Butler Chain of Lakes or Lake Bessie, storm runoff shall be treated and direct pollutant discharge shall not lower ambient (existing) water quality and indirect discharges will not significantly degrade the lakes.

(4)

Vacant, unimproved land is exempt from these regulations. Land made vacant after removal of a structure or after demolition must conform to this Land Development Code and other regulations.

(5)

Nothing in this Land Development Code is intended to relieve any property owner or developer from any obligations under state or county law or regulation to obtain any required permits.

(6)

The proposed development and development activity shall not violate the water quality standards as set forth in F.A.C. ch. 17-3. All stormwater facilities must meet the standards in F.A.C. chs. 17-25 and 17-302, and rules of the South Florida Water Management District. Stormwater discharge facilities must be designed so as to not degrade the receiving water body below the minimum conditions necessary to ensure the suitability of water for the designated use of its classification as established in F.A.C. ch. 17-302. All standards in these citations are to apply to all new development and redevelopment and that exemptions, exceptions or thresholds in these citations, including project size thresholds, are not applicable.

(b)

Design standards. To comply with the performance standards set forth in subsection (a) of this section, the proposed stormwater management system shall conform to the following design standards:

(1)

Detention and retention systems shall be designed to comply with this Land Development Code and, if applicable, county regulations.

(2)

The stormwater management requirement for development and redevelopment on properties within residential districts shall include some method or methods of on-site retention for the building, parking and driveway areas. These methods shall include, but not be limited to, the provision of swales or other retention areas, the sloping of parking areas and drives to landscaped areas versus directly to the street, the guttering of building runoff to landscaped open areas where setbacks limit the amount of pervious area available and other such methods which provide opportunities for the percolation of stormwater.

(3)

The proposed stormwater management system shall be designed to accommodate the stormwater that originates within the development and stormwater that flows onto or across the development from adjacent lands.

(4)

The proposed stormwater management system shall be designed to function properly for a minimum 20-year life.

(5)

The design and construction of the proposed stormwater management system shall be certified as meeting the requirements of this Land Development Code by a professional engineer registered in the state.

(6)

No surface water or road runoff may be channeled or directed into a sanitary sewer or into the Butler Chain of Lakes or Lake Bessie.

(7)

The proposed stormwater management system shall be compatible with the stormwater management facilities on surrounding properties or streets, taking into account the possibility that substandard systems may be improved in the future.

(8)

The side slopes and bottoms of all retention areas shall have a grass or other landscape material cover. The maximum side slopes of retention areas shall not exceed 3:1.

(9)

Spillways or other entrance channels to retention areas shall be designed to prevent the flushing of these retention areas by heavy rains.

(10)

Dry bottom retention areas shall be designed and function such that all retained water is removed after the third day. If this is not accomplished by percolation and evaporation, the retention area must be improved to include an underdrain system or other bottom materials that will accomplish this requirement.

(11)

Dredging, clearing of vegetation, deepening, widening, straightening, stabilizing or otherwise altering natural surface waters shall be minimized.

(12)

Natural surface water shall not be used as sediment traps during or after development.

(13)

For aesthetic reasons and to increase shoreline habitat, the shorelines of detention and retention areas shall be sinuous rather than straight.

(14)

Water reuse and conservation shall, to the maximum extent practicable, be achieved by incorporating the stormwater management system into irrigation systems serving the development.

(15)

Vegetated buffers of sufficient width to prevent erosion shall be retained or created along the shores, banks or edges of all natural or manmade surface waters.

(16)

In phased developments the stormwater management system for each integrated stage of completion shall be capable of functioning independently as required by this Land Development Code.

(17)

All detention and retention basins, except natural water bodies used for this purpose, shall be accessible for maintenance from streets, public rights-of-way, parking lots or other open areas.

(18)

Stormwater with wet bottom ponds shall be designed, operated and maintained so as to resemble a natural pond to the greatest extent practicable.

(19)

Any development which includes multifamily, commercial, restricted commercial or institutional uses shall provide for treatment of any storm runoff so as to preclude pollution of the Butler Chain of Lakes or Lake Bessie.

(20)

Stormwater must be disposed of in a manner that will not cause personal or property damage to up or down stream property and will not cause a rise in lake levels above the flood levels set by county, state or federal regulations.

(21)

Lake front areas are required to preserve the intact natural communities which provides filtration of stormwater runoff within 50 feet of the waters edge with only a narrow path to the water.

(c)

Other.

(1)

New or improved streets/roads shall use vegetated swale drainage and properties adjoining new or improved streets/roads shall be required to come into compliance with the town's stormwater regulations concurrent with the completion on the road construction. Where improvements are not completed by the property owner, the town, 20 days after notifying the owner, shall make such necessary improvements and bill the owner. Should payment not be made within 60 days of transmittal of the bill, a lien shall be filed by the town.

(2)

It shall be the duty of the property owner to provide proper maintenance of any stormwater system, to include swales along streets in front of their property so as to meet the requirement of this Land Development Code. This includes not filling swales with grass, dirt, sand, or grass clippings. The town shall have the power to inspect systems, facilities and swales and to require maintenance, repair and replacement of facilities as necessary. Should required correction not be made within 20 days, the town may make needed improvements and bill the owner and as stated in subsection (c)(1) of this section, a lien shall be filed.

(3)

Swimming pools or other water storage facilities shall not be drained into streets, canals or lakes without permission of the town manager.

(Ord. No. 91-6, § 3(6.05.04), 2-11-1992; Ord. No. 94-2, § 1(c, j), 2-8-1994; Ord. No. 2006-03, § 6(6.05.04), 6-9-2009)