There's a reason the water in Lake Seminole is sometimes pea-green.
Levels of nitrogen and phosphorous in the roughly 700-acre lake are more than four times higher than state standards, county officials say. The chemicals come from rainwater laden with dog waste, lawn fertilizer and sewage — the perfect mix for huge algae blooms that discolor the water.
Some of that water flows into Boca Ciega Bay, raising concerns of red-tide outbreaks.
Lake Seminole is one of about 25 bodies of water that Pinellas County is required to clean up under a new state permit that may require millions of dollars of investment in the county's aging stormwater treatment system.
Now county officials are considering charging residents in unincorporated Pinellas to pay for that work.
The commission took a first step last week, voting to reserve the right to introduce a stormwater fee this year. A final decision likely will be made after a report on the county's stormwater system is completed in April.
Unlike some Pinellas cities that bill residents, the county does not have a dedicated funding source for stormwater cleanup. Instead, it uses money from its general fund and gets some revenue from gas taxes.
That left the program vulnerable to the real estate crash and the resulting recession. Faced with declining revenues, county leaders cut almost 120 positions, including many maintenance workers from the county's stormwater and transportation department.
The cuts came at a time when the county's system was already overdue for a major overhaul. About 28 miles of corrugated metal pipes installed in the mid-1970s need to be replaced. Badly corroded, the pipes sometimes collapse, causing holes in roads and flooding.
"We really haven't invested enough over the years in ensuring that we're taking care of it," said Kelli Levy, section manager of the county's watershed management division. "Now we're dealing with old pipes and water quality issues."
How much residents would be billed if the county moves ahead with the new assessment has not been calculated yet.
The owners of single-family homes in Clearwater pay about $13 per month. The equivalent fee in the city of St. Petersburg is $6.84.
Commissioner Norm Roche said he wants to see more information on the system and whether the county's fertilizer ordinance is making a difference before he agrees to a new fee.
The county is only keeping the fee option open, Commission Chairman Ken Welch said. Because many rivers and ditches cross municipal boundaries, it's important that the county update its stormwater system, he said.
"We don't have a funding mechanism for the unincorporated county," Welch said. "The cities are saying you need to come up to speed."
Protecting the area's lakes, rivers and coastal areas is seen as crucial for Pinellas's tourist-based economy. Florida's climate and Pinellas County's dense population does not make that easy.
About half of the Tampa Bay area's annual rainfall of 50 inches falls in a period of just four months. Most of it flows back through rivers and ditches into Tampa Bay and the Gulf of Mexico.
En route, the water picks up dog waste, pesticides, fertilizers, grease, dirt and oil from cars.
There is more at stake than water quality. About 30 percent of Pinellas County lies within coastal flood zones, areas historically prone to flooding.
Rainwater just lies on the ground with no obvious escape route because of Pinellas County's pancake-flat profile.
"It's like trying to drain water off a pool table," said Mike Connors, public works administrator for the city of St. Petersburg.
Compounding the problem is that much of Pinellas County was built out by the early 1980s, before tougher environmental laws were passed requiring developers to build stormwater retention ponds, Levy said.
That means the county has to retrofit retention ponds and other water-treatment measures into built-up areas.
The county is spending $11 million to do just that to areas around Lake Seminole. The project includes new retention ponds and the addition of aluminum sulfate to ditches.
The compound causes fertilizer and other pollutants to bind together and sink to the bottom of the ditch rather than flow out of it. The contaminants can then be cleared out during routine maintenance.
Levy said she would like to see the county introduce a fee and thinks residents will support it.
"People want to live, work and play in a place that is beautiful," she said. "We're hopeful when people are given the right information and they evaluate it, they will say, 'This is important to me.'"