On July 18, a fast-moving intense summer thunderstorm whipped through the region, resulting in a short burst of rain - and a flood of raw sewage into the water.

Here's what it looked like in Kingston:

That is a combined sewer overflow (CSO) into the tidal Rondout Creek, part of the Hudson River Estuary. The plume stretched as far as the eye could see toward the mouth of the Rondout Creek, where it meets the Hudson. Kingston has taken important steps to monitor its discharges and reduce flows, including through a system that maximizes flow to the treatment plant. The city is diligent about Sewage Pollution Right to Know compliance for CSOs, and reported this discharge as required, though I still had the displeasure of telling two people who were getting ready to weed the docks in the post-storm sun what they'd just missed. They opted to wait for another time to do their waterfront work. We've seen storms move through right before student rowing teams enter the water, and we've seen kids drop fishing lines (despite "no fishing" signs) right beside the green signs that indicate the points where the CSO discharges to the creek. CSO discharges here are not usually so obvious.

Combined sewers carry both raw sewage (laced with pharmaceuticals and other household chemicals) and runoff (including oil, grease, road salt, litter and other road pollution carried off when the rain courses over the pavement into storm drains). Grass clippings figure prominently in the surface detritus in the video above, along with cigarette butts and bottle caps. Imagine a storm drain on the street and your toilet, both emptying into your creek or river together in a torrent. That's a CSO.

There are 58 CSOs, each something like this in the Hudson River communities of Westchester County, Newburgh, Poughkeepsie, Kingston, Hudson, Catskill and the U.S. Military Academy at West Point. There are about 90 more in the Capital District, another 52 in the Mohawk River and 12 more in the Upper Hudson north of Troy. New York City has at least 426 CSOs, and New Jersey's Hudson River shoreline another 26.

Some of them have discharges that are far more gruesome than the one caught on video yesterday in Kingston.

The landmark $2.5 billion Clean Water Infrastructure Act, and its predecessor the Water Infrastructure Improvement Act, will help to reduce these overflows. Communities are making investments under Long Term Control Plans required under the Clean Water Act, as enforced by the Department of Environmental Conservation, to reduce overflows significantly over then next 15 years. The progress is uneven - exemplary in some cases, but not all.

$2.5 billion, incidentally, is roughly the documented cost of wastewater infrastructure fixes needed just in the Hudson River Watershed - not including huge investments needed in New York City or New Jersey. In just a portion of that watershed - the 10 counties between the Capital District and Yonkers - only about 30% of communities have even documented their need for wastewater improvements. So the overall bill to stop sewage overflows and leaks, and to improve treatment to meet the needs of wildlife, recreational users - and the 100,000 people who rely on the Hudson for drinking water - is much larger.

New York's landmark statewide investments are a badly needed and welcome down payment. And we have to do more. You can join Riverkeeper in our efforts to advocate to stop pollution. We rely in part on the most extensive water quality dataset of its kind, and the power that comes from gathering those data through community science. Every sample gathered is a vote for clean water - and we're accumulating a lot of votes, with more than 425 locations sampled each month. The data clearly show that CSOs are a major problem, but the data also show that our problems are even more pervasive, thanks largely to the extreme age of our infrastructure, and the resultant leaks and overflows.

What else can you do? Here's a challenge: Start to contemplate what would it take to keep enough runoff out of the storm drains during rain storms in your neighborhood to prevent overflows into your creek or river. How many roof gutters can be disconnected from storm or sanitary sewers? Where would green infrastructure need to be installed to capture the most water, so that the ground can naturally slow down and treat the rain water? Time to get creative. (Check out this guide for some ideas.)