SAND BY-PASSING AT HILLSBORO INLET, FLORIDA (D 



by 

 Thelbert K. Hodges - Engineer 

 U.S. Army Corps of Engineers 



Miami Sub -Office of 

 Jacksonville, Florida, District 



Location 



Hillsboro Inlet is a natural inlet in Broward County, on the 

 southeast coast of Florida. As shown on Figure 1, the Inlet is 

 located about 36 miles north of Miami. The towns of Hillsboro Beach 

 and Pompano Beach are located to the north and south of the inlet, 

 respectively. The United States Coast Guard Hillsboro Lighthouse 

 is located on the shore immediately north of the inlet. The light- 

 house was built in 1907. 



General Inlet Features 



The aerial photograph (Figure 2) depicts the general features 

 of the inlet. The inlet is protected by a rock reef (as indicated in 

 Figure 3) to the north of the inletj the reef has a length of $80 

 feet exposed at mean low water, and at a point 70 feet north of the 

 southern end it is about 68 feet wide and 3.5 feet high above the 

 plane of mean low water. Sections normal to the shore indicate that 

 the top of the reef is convex in shape and relatively smooth. The 

 reef has a gradual slope on the seaward side and a very steep slope 

 on the landward side. The rock reef dips as it crosses the mouth of 

 the inlet, giving a controlling depth to rock of 5 to 6 feet at mean 

 low water. The rock rises again above mean low water level at about 

 600 feet south of the mouth of the inlet. The southern reef is 

 partially exposed at low water and acts as an offshore breakwater. 

 The high water shore line on the south side of the inlet is in 

 effect about 700 feet landward of the reef line. 



Prior to improvement, Hillsboro Bay was characterized by a 

 "middle ground" shoal. The natural channel in the bay lay between the 

 shoal and the north shore. The channel usually had a controlling 

 depth of about 1 foot (mean low water) across the sand bar at the 

 mouth of the inlet. Residents of the area indicate that at one time 

 the sand bar completely blocked the entrance, and was opened by hand 

 shoveling. 



(l) Any inquiries relative to this article should be directed to the 

 author . 



