They might even make money.

The first, AquaLutions, is a “filtration-type system,” said Paul Wiebke, head of the city’s stormwater division. The second, the Algal Turf Scrubber, essentially uses pollutants as fertilizer.

“They’re worth investigating,” Wiebke said.

Why

Durham, like other jurisdictions in the Falls and Jordan watersheds, is under a state mandate to reduce how much nitrogen and phosphorus tributaries running through the city send to the lakes.

The city estimates that even partial compliance, curbing pollution from existing development alone, will cost more than $595 million. Buying land, building and maintaining established measures such as retention ponds, sand filters and artificial wetlands, “is really expensive,” Wiebke said.

But new technologies are being tested and used elsewhere, and Durham stormwater staff has picked two for investigation.

AquaLutions

• What: A treatment and filtration system invented and patented by AquaFiber Technologies of Winter Park, Fla. ( bit.ly/Y3J4Ky)

• Why: In use at a Florida lake, the system has achieved a 50 percent reduction in nitrogen and a 70 percent reduction in phosphorus. Durham will be its first test in North Carolina.

• Profit potential: The Florida system produced algae that, when tested, proved usable for conversion into jet fuel. So far, however AquaFiber is “not speculating on (the) potential for commercial scale performance.”

• Contract: $79,017 (with $87,000 contingency fund) for Cardno ENTRIX, an environmental consultant with a Raleigh office, for feasibility research and designing a pilot study.

• Where: Ellerbe and Little Lick creeks.

• Status: City Council approved Jan. 7.

Algal Turf Scrubber

• What: A thin membrane with an attached screen that cultivates naturally occurring algae fed by nitrogen and phosphorus in treated water; developed and trademarked by HydroMentia Water Treatment Technologies of Ocala, Fla. ( bit.ly/Y3J4Ky)

• Why: Turf Scrubber is in use in New York, Texas and Florida with pilot studies under way in Florida, Pennsylvania and Maryland. Reported nitrogen removal rates are 13 percent to 38 percent, phosphorus removal rates up to 60 percent.

• Profit potential: The algae is regularly harvested for conversion into salable compost, livestock feed, garden container material or biofuels.

• Contract: $52,470 (with $5,330 contingency fund) for Biohabitats, an environmental consultant with a Raleigh office, for feasibility research and designing a pilot study.

• Where: To be determined.

• Status: On Monday’s City Council agenda.