Lake Erie water levels will continue a downward trend, according to the January lake level forecast from the U.S. Army Corps of Engineers. The Corps is calling for June water levels to be about 8-9 inches lower than June 2002 levels, and this is similar to levels observed in June 2001.

Roughly 90 percent of Lake Erie's water is provided by inflow from the Detroit River, coming from the three upper Great Lakes. Therefore, adequate winter precipitation in the upper Great Lakes basin is a key factor in maintaining Lake Erie's water level.

According to the Corps' report, precipitation in the upper Great Lakes Basin has been below average this winter. December precipitation for the Lake Superior Basin was 67 percent lower than normal. In the Huron Michigan Basin, the December precipitation rate was 57 percent lower than normal. In the first three weeks of January, the Superior Basin had received only six percent of normal precipitation and the Huron-Michigan Basin received only nine percent of normal precipitation.

NOAA's Climate Prediction Center links the unfavorable precipitation forecast to the now "mature" phase of the current EI Nino condition dominating the tropical Pacific Ocean. The Center predicts that the remainder of the northern winter will see drier-than average conditions over the Ohio Valley and much of the Great Lakes. Much of the upper Great Lakes region currently is classified as being in moderate to severe drought, with drought conditions expected to intensify and expand at least through April 2003.

Unless precipitation increases substantially over the next two months - which appears unlikely Lake Erie boaters will see low water levels and increased boating hazards similar to those experienced in 2001.

Lake Erie boaters should remain aware of minimum water depths in their boating areas and of underwater obstructions such as reefs and shoals. Also remain cautious while boating on days with strong westerly and southwesterly winds, which can temporarily lower the lake level further, making shallow harbors difficult to re-enter.

Anyone strolling on Lake Erie beaches during recent summers saw the differences-beaches wider than normal, vacationers cautiously edging their boats away from visible reefs, and docks resting several feet higher than the vessels connected to them. Unlike the 1980s where shoreline property owners battled erosion caused by high water levels, since 2000 the shipping industry and recreational boaters have struggled to get their vessels through low waters. What was a common Lake Erie water level of 574.1 feet in July of 1997 dropped to a surprising 571.7 feet three years later. So who's responsible? Solely Mother Nature.

Like all the Great Lakes, Lake Erie's water is governed by a natural circulation system in which water evaporates from the Lake, condenses to form clouds and is returned to the earth's surface as precipitation. Water enters the lake basin as precipitation directly over the lake's surface, from groundwater, from runoff from the surrounding land, and from tributary rivers and streams. Yet about 80 percent of Lake Erie's water comes from the upper Great Lakes through the Detroit River (see above). Water evaporates from the lake's surface when it comes in contact with dry air, forming water vapor. The vapor stays as a gas, or it condenses to form fog and clouds. When clouds form, precipitation falls, creating a continuous hydrologic cycle.

Lake levels are affected mainly by wind set-up and by changes in precipitation, both locally and throughout the Great Lakes basin. Fluctuating water levels in Lake Erie are natural occurrences and are primarily a result of changes in the amount or rate of precipitation. Because precipitation during the winter is likely to be stored as snow pack or frozen ground water, Lake Erie experiences its lowest lake levels during late winter. The combination of runoff from melting snow and ice (both locally and from the upper Great Lakes) and increased local precipitation tends to produce higher lake levels during the spring.

Wind set-up is caused by the persistent blowing of wind in a single direction over a prolonged period of time. This produces a "piling up" of water at the downwind side of the lake, triggering the level at the opposite side to drop by the corresponding amount. This natural phenomenon can result in extensive spring flooding at Buffalo, New York during a prolonged strong west wind, or flooding in Port Clinton during an extended strong east wind. When the winds cease, the water will eventually return to its original level.

Because Lake Erie is a highly dynamic system with complex processes, water levels will naturally fluctuate due to seasonal, short-term, and long-term changes. Seasonal fluctuations in water levels are based mainly on changes in precipitation and runoff to Lake Erie. Although precipitation is fairly constant throughout the year, the winter snow pack does not contribute to the lake level rise until the spring thaw and related runoff. Thus, the lake is always at its lowest level in the winter. The biggest factor influencing Lake Erie water levels is the amount of snow and ice melt received from the upper Great Lakes through the Detroit River. The combination of snow melting and spring rains contribute to seasonally increasing lake levels from early March through early August. Evaporation is greatest in the fall and early winter when Lake Erie is relatively warm and the air above the lake is cold and dry. It can also be very significant during the long, hot cloudless periods of July and August.

Lake levels are also affected by day-to-day changes. These short-term fluctuations are due to storms, wind, or ice jams and usually last from a few hours to several days. Ice jams in the Niagara River, for example, will decrease the amount of water flowing out of Lake Erie, temporarily increasing the lake level. Sustained high winds (wind set-up) can also cause short-term fluctuations, as described above.

Long-term fluctuation occurs over a period of years and depends on how wet or dry and hot or cold the weather is around the entire Great Lakes basin north of and including Lake Erie. Lake Erie experienced extremely low levels in the late- 1920s, mid-1930s, and in the mid-1960s. Extremely high levels were experienced in the early 1950s, and the mid 1970s, 1980s, and 1990s. During the last few years, precipitation levels within the Great Lakes basin has been below average, which has contributed significantly to our current low lake levels.