Tidal Gauge Data

If you have trouble viewing this data Click Here to view it in your browser.

The tide gates are kept open to allow for the rise and fall of saltwater in Straits Pond. This rise and fall occurs as a semi-diurnal tidal cycle with two episodes of  high water and two episodes of low water with each lunar day. The tides allow for the exchange of Pond water into the Weir River estuary and out to Boston Harbor when draining towards low tide.  New Boston Harbor and Weir River estuary water returns into the Pond with the incoming tide.  The tide gates are set to trigger closed (when in automatic mode) when the water level reaches 3.55 ft NAVD88 in order to prevent flooding to lower-lying properties along the Pond.

Note: currently (summer, 2020) the automatic function is under repair.  When water levels in the Pond are predicted to exceed 3.55 ft NAVD88 – which is typical during Spring tide events (which occur twice monthly during the new and full moon phases resulting in higher high tides) – the gates are manually lowered to about 80% open which dampens the tidal exchange during higher than average water levels and prevents potential flooding. The tide gate is fully opened after the spring tides period . You will see the semi-diurnal tidal cycle reflected in the water levels of the Pond remains uninterrupted during these periods and the ecological connectivity between the Pond, the estuary, and Boston Harbor is preserved.