(1) Single-family parcels.
a. Since the cost of measuring and computing the impervious area for each individual single-family parcel greatly exceeds any benefit derived from individual measurement and computation, the area of each single-family parcel constitutes a reasonable proxy for impervious area using the following formula for calculating the number of ERUs attributable to each parcel.
Total ERUs = 1.0+0.87 (Total Parcel Area - 10,000)
(10,000)
b. In no case shall the total number of ERUs for any single-family parcel be less than one.
(2) Multi-family parcels.
a. The city shall classify each multi-family parcel as either low density multi-family or high density multi-family and calculate the total ERUs for each multi-family parcel in the following manner:
Total ERUs = Total DUs+0.87 (Total Parcel Area - DUs(10,000))
(10,000)
(c) Nonresidential developed property.
(1) Parcels that are classified as nonresidential developed property shall use the following formula to calculate the number of ERUs:
Total EDUs = Impervious Surface Area
EDU Value
Total ERUs = Total EDUs+0.87 (Total Parcel Area - EDUs(10,000))
(10,000)
(2) In no case shall the total ERUs be less than the total EDUs.
b. The private stormwater facilities located in the development project in which the subject property is located are fully functioning and operating throughout the year in a satisfactory condition and in accordance with the City permit as determined by a registered professional engineer licensed in the State of Florida. A private stormwater facility shall be determined by a registered professional engineer licensed in the State of Florida to be in satisfactory operating condition so long as the stormwater facility is maintained throughout the year and operating in a manner such that the stormwater runoff from the development project is not contributing to stormwater problems in the local area in which the development project is located. The development project shall be required to provide annual report recertified by a registered professional engineer licensed in the State of Florida that the private stormwater facilities located in the development project are functioning and operating in a satisfactory condition and in accordance with the City permit. In addition, the engineer shall certify the system is maintained throughout the year by conducting two inspections per year, one inspection within the months of November thru April, and the second within the months of July thru September. The results of said inspections shall be submitted to the Stormwater Director. If the Stormwater Director determines at any time during a fiscal year that the private stormwater facility is not satisfactorily maintained on or is no longer located in the development project, then the development project shall be required to remedy situation and shall forfeit the aforesaid credit for the current and subsequent fiscal year(s) during which time the subject properties shall be treated for purposes of this Chapter 22 in the same manner as properties which do not meet all of the conditions necessary for the credit until such time as the situation has been remedied to the satisfaction of a registered professional engineer licensed in the State of Florida.
c. The certification submitted by the Florida Registered Professional Engineer shall include, but is not limited to, the following information: Date of inspection, name of person conducting the inspection, location map, date of City permit, the development project plan depicting existing improvements, and documentation of the condition of the stormwater features including, but not limited to, perimeter berms, detention or retention ponds, control structures, weirs, catch basins/inlets, trench drains, swales, pipes, exfiltration systems, oil/water separator, littoral zones, rain gardens, and wetland storage systems.
Stormwater Treatment Areas, or STAs, are constructed wetlands that remove and store nutrients through plant growth and the accumulation of dead plant material that is slowly converted to a layer of peat soil. Five STAs south of Lake Okeechobee are now removing excess nutrients from agricultural runoff water and, in some cases, runoff from urban tributaries, before discharging it into the Everglades and other natural areas. Two more STAs north of Lake Okeechobee are now in the planning stage.
At present, these STAs south of Lake Okeechobee have an effective treatment area of 57,000 acres, which includes STA expansions completed in 2012 in the Everglades Agricultural Area (EAA) that added nearly 12,000 acres of treatment wetlands. North and east of Lake Okeechobee, STAs are also used to remove phosphorus from water flowing into the lake, St. Lucie Estuary and Indian River Lagoon.
Cities and communities also contribute nutrients and other pollutants to our region's rivers, lakes and wetlands. Storm water flowing over city streets or the rich green lawns and gardens that fill our urban and suburban landscapes can carry excess nutrients from the fertilizers and herbicides we use, as well as all the other contaminants that are a by-product of modern life.
Local governments and developers are also required to adopt Stormwater Best Management Practices, or BMPs, that make sure that water flowing into our natural ecosystems is cleaner. These BMPs include keeping direct urban stormwater runoff away from waterways, retaining and cleaning stormwater or irrigation water "on-site" and reducing the amount of water used for irrigation, as well as the type and quantity of fertilizers and pesticides or herbicides used on our landscapes