An apparent dividing zone for nearshore nontidal drift currents 
moving to the north- induced by the outflow from Chesapeake Bay striking 
roughly southeast (Figure 4)- and nontidal drift to the south induced by 
the prevailing oceanic currents from the north, is found in the vicinity 
of Rudee Inlet (Figure 4). This inference seems to explain the scarcity 
of drift bottles recovered in the vicinity of Rudee Inlet (for bottles 
out long enough to be influenced by the nontidal drift) and the longer 
residence time in the sea of most of the bottles released near Rudee 
Inlet (that were recovered from 2 to 10 days after their release). 
Figure 10 shows the inferred average nontidal circulation as based 
on these measurements. Although the center of the clockwise eddy is by 
no means known, it is believed to be placed here (Figure 10) in its most 
logical position. Additional measurements, perpendicular to shore, would 
be of great value in this area. The presence of Rudee Inlet in the area 
of diverging currents may be additional confirmation of the validity of 
this circulation model (Figure 10), for currents transport sand across 
mouths of inlets and close them. The sand deposits at Cape Henry that 
are indicated by the bottom contour shown on the nontidal drift diagram 
(Figure 4) similarly reflect the area of converging currents shown in our 
model (Figure 10). 
The dimensions, position of the center, and rates of water movement 
in the eddy system will all vary as the pressure gradient undergoes 
modifications by runoff variations and/or the frictional drag of winds 
(especially from the north) and longshore and nearshore currents. 
Tidal currents in the area are generally moderate to strong, maximum 
velocities of 1.6 m/sec (3.0 kn) having been noted on the ebb and 0.87 
‘m/sec (1.7 kn) on the flood, at the Cape Henry station. The characteristic 
of the ebb tidal current to sweep surface water southward and toward the 
shore between 3 and 9 hours after flood at nearly all three stations has 
been observed (Figure 4). Bottom water, however, tends to move directly 
onshore or northward and obliquely toward the shore between 8 hours after 
flood and flood, and between flood and one hour after flood, in the central 
portion of the area (Figure 4). 
The detailed current data and inferred circulation model presented 
here are being used for prediction studies of the inshore transportation 
of sediment and the design and positioning of sewage outfall structures. 
It is hoped that the techniques and findings presented will provide some 
guidance to other workers planning similar investigations of nearshore 
currents and circulation at the mouths of estuaries. 
