Green Infrastructure

Green infrastructure is about "working with the grain" of natural systems, rather than against it.

The old concept for building cities was "grey infrastructure"--where the "grey" refers to concrete, pavement, and other structures that prevent rain from soaking into the ground.

Over a hundred years ago, city streets were wallows of mud.  That's why high leather boots were in fashion--to keep the mud out.  First cities build boardwalks and bumpy roads made of logs.  When asphalt became available--it seemed like the ideal solution. 

But once everything was paved, new problems emerged.
  • Flooding, because the rain ran off rapidly in storms.
  • Erosion--because streams became overburdened with the floods.
  • Groundwater wasn't replenished.  Springs and streams dried up.
  • Pavement collected pollution--which quickly flushed to the lakes when it rained.
Some examples of green infrastructure...
  • Rain gardens infiltrate rain where it falls
  • Green roofs keep buildings cool, absorb rainwater. 
  • Porous pavement--allows rain to get in
  • Green swales and sediment ponds--instead of stormwater pipes
Green infrastructure is by nature decentralized.  It aims to handle the problems where they occur, where the rain falls.  Being decentralized, in the end they will cost less and work better.  However, green infrastructure meets resistance because it's new, and a bit harder to plan, because so many more people are involved.  But in the end, it will create community spirit, as people plan and work together.

Examples of progress in Madison

Madison is making slow progress towards green infrastructure, but it lags behind many other cities.
  • The City is undertaking a comprehensive study of the Lake Wingra watershed.
  • Monroe Street will be reconstructed in 2012 with green infrastructure features.
  • Madison is developing a standard for green streets.
  • More rain gardens are being constructed (but not nearly enough!)