Environmental advocates say the best data on Inner Harbor water quality comes in snapshots — samples taken every other week.
But a new monitor to be placed at the mouth of the Jones Falls, part of a White House initiative to revitalize Baltimore's environment, will provide detail on pollutants entering the harbor by the minute.
Advocates say that could improve their understanding of how pollution flows through local waterways and help show city residents the impact on the environment.
"Having a real-time device so we can see the trends throughout the day, throughout the week and throughout the year will give us a better idea of what's flowing into the harbor and when that's happening," said Adam Lindquist, director of the Healthy Harbor Initiative.
On Friday, the U.S. Geological Survey and Environmental Protection Agency announced plans to install the monitor early next year. Officials gathered in West Baltimore to unveil the initiative, part of a package of programs designed to help improve neighborhoods and stimulate the economy.
Agencies are calling the monitor the nation's first "Village Blue" station, modeled after an EPA program called "Village Green" that is focused on boosting awareness of air pollution.
Instruments will measure water temperature, salinity, oxygen content, pH, clarity and, eventually, levels of nitrogen pollution. The data will be transmitted directly to an EPA website being designed for the average person to understand.
"This initiative will provide the public with access to and understanding of water quality data they can use in a number of important ways," EPA regional administrator Shawn M. Garvin said in a statement.
"The information will help people become better stewards of their local waterways and take actions to protect their health by reducing exposure to contaminants," Garvin said.
The data is similar to what local advocacy group Blue Water Baltimore already collects. Its samples are used to monitor for major sewage leaks or other contamination, and the data is summarized every year in an annual report card published by the Healthy Harbor Initiative.
In 2015, the Inner Harbor, Jones Falls and tidal Patapsco River received failing grades for a third straight year. The results are challenging a goal to make the harbor swimmable and fishable by 2020.
The new instruments, expected to be installed on a footbridge near the Pier Six Pavilion and on Mr. Trash Wheel in the spring, will show how harbor water quality changes amid major rainstorms, strong winds or even sunny weather.
At the location where the Jones Falls meets the Patapsco River, the data also could show how much pollution the stream is introducing to the river. There aren't any instruments measuring the flow and volume of the Jones Falls, said Alice Volpitta, a water quality manager for Blue Water.
While the organization posts its most recent water quality data on its Harbor Alert website, the new monitor will provide even more up-to-date information for anyone who might be planning to kayak or is curious how weather is affecting water quality.
"This is the first time we're really going to have an idea of what's happening in that zone," Volpitta said.
The EPA is expected to launch the Village Blue website next summer, and will also add signage near the water monitor to explain what it is measuring, said Mary Kay Foley, director of the USGS' Maryland-Delaware-DC Water Science Center.
Other programs within the larger initiative include expanding a wildlife refuge in the Masonville Cove area of Brooklyn to cover the entire Middle Branch watershed and building "schoolyard habitats" to serve as outdoor classrooms at 10 city schools.
The projects are being backed with about $750,000 in federal grants.