Waterworks of Ancient Plyos
Ivanovo Institute of civil engineering
The formation of river flow occurs in a specific physical-geographical environment, and the regime of rivers respond to all meteorological and hydrological processes within a river basin. Interest in this plan represent a unique stone ridge “Wine” and “Slash”, downstream of the Volga river and a distance of 5-8 km from the city of Plyos. There is an assumption that these ridges have survived to the present, served as governing waterworks, was crossing the gateway to Plyos defensive-customs system that existed in XY century.
At the present time, in connection with the formation of the Gorky reservoir, these ridges are submerged to a depth of about 8 m, but retained a clear outline wyprawionych structures.
Analyzing the sailing HU mid-twentieth centuries. unique measurements of ridges, made in the 30-ies, the materials of survey plots adjacent to the ridges and up and down the river, the widths of soundings of the riverbed, as well as the materials of the expedition IICI 1985 to study the strength characteristics of the material of the dam can do the following hypothetical conclusions:
I. Starting from picket PC 0 80 PC interest is turning vane dam is made oblique on the river with the angle from the normal does not exceed 15°. Turning vane dam left Bank had the purpose of protecting the shore from intense erosion by the river current, and TA oke defended the coast from erosion.
II. On PC 0 which flows into the Volga river, as evidenced by found the bed of the river near this picket, turning vane dam has a trapezoidal cross-section, consists of a body, root and head. Head to PC 3+80 has undergone a number of changes over a long period of time and part of it is blurred and destroyed by people. Along the outer slope of the dike there is a strong down current, so as to resist the action of the currents and ice drift the outer slope was less steep (1:3) including coastal cliff worked in more favorable conditions, his inclination is made steeper. The crest of the turning vane dikes was subject to strong wear, which factored into its implementation, because it is made from a width of 4 meters and more.
Field survey confirms the hypothesis about the artificial origin of these dams, because the descriptions of divers stone in the stream directing dam tight and reminiscent of cobblestone “pavement” with a smooth surface. The edges and slopes lined with large (up to 50 cm) boulder stone and have a slope of more than 60°, the middle paved with smaller stones (15-30 cm). On either side of the ridge the bottom is sandy, clean, the stones are not detected. Probably for the attenuation of longitudinal currents in the space between the dam and the shore at high levels (spring and autumn flood), when the water is spilling over the dam and to deposits of silt here, the turning vane dam connected with the shore by transverse structures (traverses). Travers is seen about 3 Grand. This is evident by the measurements on the widths on your PC 1+60 to 2 PC+60.
To stream directing dams were presented with the following requirements:
– Stroiservice built the dams so that they are a continuation of the leading Bank and pushed into the river bed by 1/3 of its channel. The backfilling was conducted from upstream to downstream, which is evident from the granulometric composition. Because the entrainment of the lighter stones in the lower part of the dam, the crest of the traverse has the same mark as the root of the dam.
– the most important factor when determining the minimum weight of pieces of stone laid in the dam, was the force of the current of the river. It can be traced to the fact that the pieces of stone weighing up to 3 kg were demolished over down along the axis of the dam.
The body of the dam drains freely, so in the body of the dam screenplease the fines content (pieces with a diameter 15-30 cm) does not exceed 15%, because a large weight of small pieces, it would be difficult filtering water through the body of the dam and would help to offset large pieces of rock. An example of such a dam is the placement in the dam General in Switzerland, dikes of Holland, Belgium, England.
The right-Bank artificial structures resemble Zaton – place lay-bys in the winter time, place, repair, launching, unloading, etc. turnover to the basin having a maximum depth greater than 3 m. their Width not more than 30 m. the backwater protected from the river by the stream directing dam from PC 1+PC 90 to 5+70. The elements of the rear part of Creek with 5 PCs+50 PCs 8 are built using materials of the boulder-gravel-sand Deposit (local).
The coastal part of the basin of the right Bank also has large depth and, most likely, between the pickets PCs 5+00 and PC 8 were waterfront structures (pier, port, etc.). Boulder ridge, located located along the right Bank from PK 2+00 to PK 5+00, presumably, served as a pier for mooring ships. To confirm this hypothesis it is necessary in the place of Zaton to perform diving operations for inspection of the bottom of Eaton, where not excluded the possibility of detecting sunken objects Volga rivermen (anchors, working tool used during the repair and launching of vessels on the water), finally, the remains of the quay wall.
The channel is formed between the turning vanes dam right Bank and jutting out into the river channel embankments of the Creek, had a width of 90 m, and allowed without interference to pass vessels with cargo on the river, as well as to go and zahoditi from Zaton. We can assume that this place was controlled gate for the further advancement of ships.