The costs of wasting P: P remediation in ONE lake to cost $5-10M
Here’s an example of the “external” costs of agricultural P runoff: the EPA is treating Grand Lake (Ohio) with alum (a chemical that reacts with phosphate to remove it from the water column to the sediments) to reduce algal blooms that often make the lake “off limits” to swimming and other uses.
Estimated cost: between $5 and 10 MILLION dollars, just for one lake.
In a related and perhaps even more surprising story, the state of Michigan is considering a BAN on P fertilizers and this proposal has been endorsed by the editorial board of Grand Rapids Press (link). While the proposed ban deals only with fertilizers used for lawns and golf courses, this is still pretty surprising in a heavily agricultural area. It illustrates a conundrum: people like their lawns green and their lakes blue. But it’s often the case that you can’t have both at the same time!
Check out the EXTREMELY green waters of Grand Lake: