All across our great state, Marylanders are sharing the responsibility of cleaning up our polluted waterways. Residents should not and will not accept the frequent occurrence of algae blooms, dead zones, sick fish and "no swimming" signs in our rivers, streams and the Chesapeake Bay.

Thankfully, Maryland is making progress to reduce pollution to meet our obligations under the federal-state Chesapeake Bay Blueprint, a comprehensive cleanup plan for the bay. We've made terrific strides on implementing state-of-the-art technologies at our sewage treatment plants. There are efforts underway in our most populous counties to tackle polluted runoff. We've also put policies in place to protect against new pollution loads from uncontrolled sprawling development. All of these steps are necessary to improve our local waters and to stay on track to achieve our goals.

However, even as we've moved forward with these important steps, we could be on the verge of moving back on another.

Agriculture is the single largest source of pollution to the Chesapeake Bay, and runoff from manure spread on farm fields is a major source of phosphorus pollution. Crops need phosphorus from fertilizers such as manure, but too much of a good thing leaves farm fields saturated, creating the risk of phosphorus runoff polluting nearby waterways and the bay.

Maryland and other bay states have used a tool called the Phosphorus Site Index since 2001 to calculate the likelihood of phosphorus from a farm field polluting a nearby waterway. This tool is now out of date, science having established the need for fundamental changes.

Using this science, Maryland has developed a new, more accurate tool: The Phosphorus Management Tool (PMT), based on 10 years of research, will replace the site index. This new tool will reduce the amount of phosphorus pollution going into our rivers, creeks and streams.

To put it simply, the new tool will tell a farmer whether putting manure on a farm field will help crops grow or will run off the field and pollute the Chesapeake Bay.

Using the best science to reduce the threat of pollution may seem like common sense, but unfortunately, factions within Maryland's agricultural community are choosing to fight the implementation of this updated tool. They are demanding delay, arguing that they should not be asked to do more than they are already doing to clean our waters.

While it would be a poor choice to delay the PMT, it is really not a choice at all. We've already promised to implement it.

The PMT is a major part of Maryland's commitment to clean up the Chesapeake Bay. The unfortunate reality is that it has already been delayed: Maryland's 2010 Watershed Implementation Plan committed the state to implement the PMT in 2011.

There are legitimate concerns about storage of excess manure and about payment for transport. These concerns prompted Gov. Martin O'Malley's staff and the Maryland Department of Agriculture to convene a series of meetings this summer about the PMT with key stakeholders, including the environmental and agricultural communities. The currently proposed regulations for implementing the PMT reflect the agreement reached by the stakeholders.

But now the agriculture lobby wants another bite at the apple. It is asking for four more years of delay until 2017.

A four-year delay would mean more pollution into the bay from farms at a time when urban and suburban residents, along with local jurisdictions, are doing more to fight pollution. It simply is not fair to allow the agricultural community to backtrack as others move forward.

Along with all Marylanders, we want a clean, safe and healthy Chesapeake Bay. Reducing pollution isn't easy, but we can do it when we put the right policies in place and use the right technology. A clean bay is within our reach, but to get there, Maryland must keep up the progress, keep decreasing pollution from all sectors, and — as echoed in Governor O'Malley's 2010 campaign — keep moving forward, not back.

Doug Myers is the Maryland Senior Scientist of the Chesapeake Bay Foundation. His email is dmyers@cbf.org. Roy A. Hoagland is the coordinator of the Maryland Clean Agriculture Coalition. His email is royhoagland@hopeimpacts.com.


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