It's not a State tax though, it's limited to the 10 most populous counties. And there already is a poop tax, it's called the Flush Tax and everyone pay it, $60/year per account. The tax was doubled in 2012.
"State “Flush Tax” began January 2005…
In 2004, the Maryland Legislature took a major step towards protecting the Chesapeake Bay and its tributaries, when it passed what has become known as “the flush tax”.
The bill established the Chesapeake and Atlantic Coastal Bays Restoration Fund to be supported by a $2.50 a month fee on sewer bills and an equivalent $30 annual fee on septic system owners. Utilities customers saw a new line item on their quarterly bills beginning January 1, 2005 for $7.50 per quarter ($2.50 per month). These funds are collected by the County and turned over to the State who distributes the funds to utilities to upgrade wastewater treatment plants to reduce nitrogen discharge which causes algae blooms that harm fish, crabs, native plants and other aquatic life. The revenues from septic tank users are used to upgrade or replace failing septic systems and to provide financial assistance to farmers to help plant cover crops to prevent nutrient runoff from agricultural land."
State Flush Tax
Of course this new tax is suppose to do the same thing.
The "storm management fee," passed by the state legislature in 2012, will go into effect following a decree from Democrat Gov. Martin O'Malley.
"But first, a little background [via the The Gazette]:
In 2010 the Obama administration's Environmental Protection Agency ordered Maryland to reduce stormwater runoff into the Chesapeake Bay so that nitrogen levels fall 22 percent and phosphorus falls 15 percent from current amounts. The price tag: $14.8 billion."
Here