Implementation strategy

Where is can be applied



Barriers to implementation

Point when action may need to be abandoned

Exfiltration trenches

Any low lying area where stormwater collects, and the water table is more than 3 ft below the surface; densely developed areas where retention is not available, roadways

Excess water drains to aquifer, some treatment provided


Significant damage to roadways for installation, maintenance needed, clogging issues reduce benefits

If groundwater table is above exfiltration piping, the exfiltration efficiency diminishes quickly

Install stormwater pumping stations in low lying areas to reduce storm water flooding (requires studies to identify appropriate areas, sites and priority levels)

Any low lying area where stormwater collects, and there is a place to pump the excess stormwater to such as a canal or the intracoastal waterway; common for developed areas

Removes water from streets, reduces floodi3g

Start at $1.5 to 5 million each, number unclear without more study

NPDES permits, maintenance cost, land acquisition, discharge quality

When full area served is inundated (>3 - 5 ft SLR)

Added dry retention

Common for new development, but difficult to retrofit; developer resist because it consumes land they could otherwise develop; limited undeveloped areas in the City

Removes water from streets, reduces flooding

$200 K/ac

Land availability, maintenance of pond, discharge location

When full area served is inundated

Armoring the sewer system (G7 program)

Any area where gravity sanitary sewers are installed, which is most of the City

Keeps stormwater out of sanitary sewer system and reduces potential for disease spread from sewage overflows. Major public health solution


limited expense beyond capital cost


Central sewer installation in OSTDS areas

All areas where there are septic tanks. This includes little of the City.

Public health benefit of reducing discharges to lawns, canals and groundwater from septic tanks

$15,000 per household

Cost, assessments against property owners


Raise roadways

Limited to areas where redevelopment is occurring area-wide due to ancillary impacts on adjacent properties

Keeps traffic above floodwaters

$2 - 4 million/lane mile

Runoff, cost, utility relocation

When full area served is inundated

Class V gravity wells

Any low lying areas where stormwater collects and is located where saltwater has intruded the surficial aquifer beneath the site (generally east of Dixie Highway)

Means to drain neighborhoods

$250 K ea.

Needs baffle box, limited flow volume (1 MGD)

When full area served is inundated