For more than a year, staff at the Capital Region Development Authority and Metropolitan District (MDC) have been negotiating an agreement that would require the CRDA to help pay for the installation of a large stormwater drainage pipe, which would accept water flowing from parking lots and off buildings planned for the “Bushnell South” development area. Hartford, like many older cities in the Northeast, has a sewer system with pipes that carry both sanitary sewage — from toilets, kitchen sinks and shower drains — and stormwater. All this gets sent downstream to sewage treatment plants. That’s usually not a problem. But large rainstorms, which have increased in frequency in recent years, create sudden spikes in flow that can overwhelm sewage treatment plants, spilling millions of gallons of stormwater mixed with raw sewage into the Connecticut River. Jellison said he envisions a mile-long pipe of about 24 to 36 inches in diameter that could cost around $4 million.
https://www.hartfordbusiness.com/article/heres-how-stormwater-drainage-is-impacting-a-major-hartford-development-plan