3-41 



Transparency 



Water transparency data, as measured by Secchi disc, showed 

 that New Haven Harbor is a relatively turbid estuary. Typical values 

 ranged from 0.2 m to 2.3 m with a mean of 1.1 m. Transparency was 

 slightly greater in the outer harbor than in the inner harbor. Trans- 

 parency is affected by various factors, including phytoplankton abun- 

 dance, suspended particulate matter, dissolved materials, and incident 

 light. Thus, transparency was only used as a qualitative indication of 

 depth of the photic zone; no attempt was made to link observations to 

 specific causative factors. 



Spatial Variability Patterns 



The waters of the inner harbor show a relatively wide vari- 

 ation of physical/chemical parameters over the course of any tidal 

 cycle, season, or year (Figure 3-9, 3-10, 3-11, 3-12). Salinity, dis- 

 solved oxygen, and temperature measurements show a tendency for waters 

 from near the head of the estuary to flush seaward on the ebb, sometimes 

 temporarily being trapped in an eddy on the western side of the harbor. 



The waters of the outer harbor adjacent to Long Island Sound 

 show very little variation from flood to ebb tide, but \indergo a syste- 

 matic annual cycle (Figures 3-9, 3-10, 3-13). Thus, the outer harbor 

 shows relatively free exchange with Long Island Sound, and a tendency 

 for such waters to occupy the eastern side of the inner harbor through- 

 out the tidal cycle is noticeable. 



Quinnipiaa River 



Station 1 in the lower reaches of the Quinnipiac River, showed 

 the highest variability of salinity, temperature, dissolved oxygen, 



(Text continued on page 3-48) 



