Whatever your views on government spending, it’s good sense to make an investment that doubles your return. A study released last fall by the Brookings Institute determined that a government investment of $26 billion to clean and restore the Great Lakes would produce over $50 billion in long-term benefits to the national economy and between $30 and $50 billion in short-term benefits to the Great Lakes regional economy. To bring those numbers closer to home, the Brookings Institute released a supplemental report this week showing the economic gains for the major Great Lakes cities. Chicago, the economic powerhouse of the region, would see benefits of $7.4 to $13.3 billion. Detroit, which could use some economic love these days, would see benefits of $3.7 billion to $7 billion. No risk, high returns, and clean lakes – seems like a solid investment decision.