Dock Street Dam

Dock Street Dam
Dock Street Dam nearing completion in 1915 (top left: truss bridge of the Philadelphia, Harrisburg and Pittsburgh Railroad behind the weir)
Location: Dauphin County Cumberland County Tributaries: Susquehanna River Conodoguinet Creek Larger cities on the shore: Harrisburg and Lemoyne , Pennsylvania
Pennsylvania , United States
Coordinates	40 ° 14 '55 "  N , 76 ° 52' 43"  W Coordinates: 40 ° 14 '55 "  N , 76 ° 52' 43"  W.
Data on the structure
Lock type:	Gravity dam
Construction time:	1913-1915
Crown length:	957 m
Bridges at City Island level from left to right: M. Harvey Taylor Memorial Bridge Walnut Street Bridge Market Street Bridge Cumberland Valley Railroad Bridge Philadelphia and Reading Railroad Bridge Dock Street Dam John Harris Bridge

The Dock Street Dam is an overflow weir in the Susquehanna River between Harrisburg and Lemoyne in the state of Pennsylvania of the United States . It is located between the Philadelphia and Reading Railroad Bridge and the John Harris Bridge and dams the Susquehanna off Harrisburg by around 1.2 meters at low tide . At higher water levels in the winter months the crown of the dam can be below the lower water are, the barrage is thus a basic military and provides for occurring ice drift is not an obstacle.

history

At the turn of the century, the wastewater from Harrisburg was still untreated in the Susquehanna. In the summer months at times of low water, smaller stagnant bodies of water formed in which the sewage collected and, in addition to the unpleasant smell, led to the formation of breeding grounds for mosquitoes and other insects. With the construction of the weir between 1913 and 1915 at Dock Street , the water level was increased sufficiently to avoid standing water. In addition, by was the section of the river to the river island City Iceland be utilized for leisure and recreational purposes before Harrisburg.

description

Construction detail of the dam for the middle (right) and maximum height (left)

The 957 meter long gravity dam of reinforced concrete consists of 61 cm wide pillars erected at a distance of three meters in the river bed and in the prevailing limestone subsoil were anchored. The height of the pillars varies between 1.5 m and 3.7 m depending on the depth of the rock. The pillar side upstream was covered with prefabricated reinforced concrete slabs three meters long, 61 cm wide and between 20 cm and 28 cm thick, so that a closed area was created; the number of plates varied depending on the water depth. To seal the dam on the foundation bed were sandbags used. The weir has two openings, one 3.6 m wide in the middle part and one at the east end facing the Harrisburg bank, which was 10 m at the time of completion.

Deaths

Since 1935 there have been at least 29 fatal accidents on the dam, which earned him the nickname drowning machine . The last time a mother and her three-year-old daughter died here on May 7, 2018, when their boat below the dam came too close to its suction.

Web links

Dock Street Dam. Structurae .

Individual evidence

1. ↑ ^{a b c} Joel D. Justin: Low Concrete Dam at Harrisburg Across Susquehanna River. In: Engineering News. Vol. 74, No. 27, 1915, pp. 1250-1253.
2. ↑ Erik V. Fasick: Harrisburg and the Susquehanna River. Images of America, 2015, ISBN 978-1467122986 , p. 78.
3. ^ Christine Vendel: Harrisburg's 'drowning machine' dam has killed at least 29 people. Their stories. Pennlive.com, June 18, 2018. Retrieved June 18, 2018.