Rolling into 2020 like … a storm

A graph depicting Hartwell’s pool elevation from January 2019-January 2020.

If the first two weeks are any indication, 2020 is going to be a banner year for the Savannah River Basin.

As of today (Jan. 15), all three sub-basins have collected 5 or more inches of rain, easily besting their January averages with two weeks to spare.

This situation also has the basin sittin’ pretty as we begin our guide curve ascent toward 660 & 330 (feet above mean sea level) for Hartwell and Thurmond, respectively. Or more loosely put: It’s better to have rain in the reservoir than to be dancing for it.

But lest we count the rain before it falls for the rest of the year, let’s look back to see how we got here.

In December, the basin climbed out of Drought Level 1 thanks in large part to “Santa Claus” storms that delivered much-needed rain to the good basin leading into Christmas and New Year’s Eve.

For perspective, though, the only reason the come-from-behind victory over DL1 was so impressive is because of the stress-inducing see-saw of the previous 11 months.

Both Hartwell and Thurmond began 2019 smiling: above guide curve and with above average rain. But that’s about as stable as it got.

Thurmond proceeded to receive sub-par precipitation for the next two months, specifically with only a 51% of average showing in March, normally the wettest month.

Luckily, Hartwell made up the difference – nearly all of it in February alone – when it received 7.6 inches and pushed the reservoir well into flood storage. (It’s especially efficient to receive the bulk of the rainfall in the Hartwell basin as it can be passed through each of the dams and generate electricity each time as we balance the system.)

After February, it was all downhill from there, but not in a good way as that normally implies.

With the exception of two short upward spikes (in late April and July), the reservoirs’ observed elevation continued their downward trudge toward Drought Level 1 in the fall.

From April to September, more often than not the sub-basins received sub-par rainfall – all at a time when evaporation and transpiration are at their peak.

September was especially grim as Thurmond collected a scant 0.52 inches of rain and Hartwell, 1.4 inches (compared to their 3.5 and 4.6 inch averages, respectively).

A strong showing for precipitation in October helped stem the tide but again, the full recovery from DL1 and return to normal operations didn’t occur until the last two weeks of the year.  

So where does that leave us? We’ve seen better, but have also experienced much worse (ahem, recent droughts that will remain unnamed).

It’s a new year and a new decade, let’s let the sub-basins speak for themselves.

~ Jeremy S. Buddemeier, Corporate Communications Office

About U.S. Army Corps of Engineers Savannah District

The U.S. Army Corps of Engineers Savannah District oversees a multimillion dollar military construction program at 11 Army and Air Force installations in Georgia and North Carolina. We also manage water resources across the Coastal Georgia region, including maintenance dredging of the Savannah and Brunswick harbors; operation of three hydroelectric dams and reservoirs along the upper Savannah River; and administration of an extensive stream and wetland permitting and mitigation program within the state of Georgia. Follow us on Twitter @SavannahCorps and on Facebook.com/SavannahCorps
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