River flows into the Chesapeake Bay during 2003 were the third highest since the U.S. Geological Survey began keeping records in 1937.

The average flow into the Bay last year was 86.4 billion gallons a day, only 2.3 bgd below the record set in 1972, according to the USGS.

Flows into the Bay were higher than average from March through the rest of the year, dramatically ending four years of drier than normal conditions.

Precipitation in Baltimore last year was 62.66 inches, more than 20 inches above normal and the wettest year on record since 1889.

Precipitation in Washington was the second highest on record, only one-half inch below the record set in 1889. Average annual precipitation for both regions is about 40 inches.

The strong flows impacted the Bay. Rains and high water flows flush higher than normal amounts of sediment and nutrients off the lands and into waterways.

When they reach the Bay, the sediment clouds the water, and the nutrients lead to algae blooms.

Both of those factors combine to block sunlight from reaching underwater grass beds, which provide critical food and habitat for fish, shellfish and waterfowl. Preliminary reports from scientists indicate a widespread loss of grass beds throughout the Bay last year.

Strong flows also create a barrier that prevents oxygen-rich water on the top of the Bay from mixing with water on the bottom. This process leads to severe low-oxygen problems as algae sink to the bottom and decompose, depleting deep areas of oxygen.

Water quality monitoring showed that 2003 had some of the worst dissolved oxygen conditions ever observed in the Chesapeake.

This year, meanwhile, started out with near normal flows into the Bay. January’s average of 60.9 bgd was only 6 percent above average, although the USGS attributed part of that to the cold temperatures that prevailed that month.

When temperatures remain at or below freezing, moisture is either frozen in the ground, or stored in snow, to be released later.