Modern technologies for ichthyofauna migration over the discharge sills

Ph.D Răzvan Voicu

rzvnvoicu@yahoo.com, getiiliberi@gmail.com,

There is a strong need to achieve systems for ichthyofauna migration both for migratory

species (some endangered) and for restoring the lotic ecosystems functions. There are going to

be achieved some systems for fish migration by generally using the free flow of water through

pipes; there are few cases where the systems used are operated wholly or partly by the means of

electricity. (Elevators for fish). Lots of systems for blocking different species of fish migration

are built on water courses in various cities of the world. The system presented below will use

electricity and will solve the issue regarding fish migration over discharge sills or small dams

within cities and more.We shall have two different systems: a downstream-upstream one and an

upstream-downstream one.

The first upstream - downstream system

Solution I

A basin made of metal sheet pile to capture fish will be built near the right or the left

banks, at the discharge sill (figure 1). If the riverbed is not covered by concrete, then such works

should be performed in the basin area or at least in front of it. The downstream area of the basin

will be fixed to the discharge sill. The space between the basin area and the discharge sill will

also be covered by concrete (figure 2).

right bank

sheet pile with variable geometry

basin of metal sheet piles

Figure 1

discharge sill

Figure 2

electric motor

sheet pile 1

left bank

systems for redirecting the ichthyofauna

electromagnetic field

pile with variable geometry

discharge sill

watercourse

1 Fixing the metal sheet pile to the discharge sill

discharge sill

concrete for fixing the metal sheet pile

metal sheet pile

2 fixing the metal sheet pile to the discharge sill

sheet pile 2

electric motor

pile

The pile with variable geometry will move vertically by means of an electric motor fixed

to the sheet pile 2 and also to the discharge sill. Moreover, some systems of electromagnetic

fields are to be fixed to the floating bodies upstream of the sheet pile in order to redirect the fish

migration towards the basin (figure 1).

When operating the electric motor, the sheet pile with variable geometry will completely

close the basin due to a metal bracket fixed to the concrete plate (figure 3). After the sheet pile

with variable geometry has been folded, the river water course is redirected by the means of the

sheet piles reaching a height (calculated) so that water cannot penetrate the metal basin 1. To

obtain a horizontal movement of the sheet pile with variable geometry, there must be a difference

of a few inches between it and the concrete side of the basin (horizontal surface). For a tight seal,

a metal bracket must be fixed to the concrete surface. All materials used are stainless.

metallic grid

discharge sill metal basin 1

sheet pile with variable geometry

electric motor

metal brackets

Figure 3 Metal brackets positioning

In the upper part of the metal sheet pile fixed to the discharge sill, a metallic grid that

prevents the fish fauna from passing downstream of the discharge sill will be welded. A vertical

rectangular canal will be built in concrete basin plate and then some drilling on inclined plane

below the discharge sill will be performed. The pile allowing water to get into the rectangular

canal below the discharge sill is fixed to the concrete plate and is driven by the electric motor.

Drilling on inclined plane will be stabilized by the means of a concrete rectangular canal having

the same size as the one in the concrete plate (figure 4).

discharge sill

metal

Figure 4 Positioning

metal basin 1

sheet pile for ichthyofauna access

rectangular canal

below the discharge sill

rectangular canal in the concrete plate

ositioning the rectangular canals for fish migration

ichthyofauna access

canal in the concrete plate

fish migration

After passing under the discharge sill

(parallelepipedic) canal will reach a

discharge sill

watercourse

Figure 5 Positioning the sheet

discharge sill and without affecting its structure

will reach a basin built downstream the discharge sill (figure

sheet pile for ichthyofauna access

the sheet pile for ichthyofauna access under the discharge sill

out affecting its structure, the rectangular

(figure 5).

for ichthyofauna access

discharge sill

When the sheet pile with variable geometry is closed, the fish fauna is also blocked into

the basin. The sheet pile for ichthyofauna access is folded upright immediately allowing the

ichthyofauna to pass downstream of the discharge sill. After a few minutes sheet pile for

ichthyofauna access is folded horizontally and closes the basin. Then the sheet pile with variable

geometry is also folded and allows water to fill in the basin. There is a sensor for detecting fish

fauna in the basin and thus, after detecting a number of species, the sheet pile with variable

geometry closes automatically. This process is completely automatic and, in some areas, it can

be performed by using electricity generated by solar panels.

The second upstream - downstream system

Solution II

A basin consisting of metal sheet piles is built on the left bank at a distance of about 10

meters (calculated depending on the discharge sill). Three of these sheet piles have variable

geometry and are situated under water (figure 6). If the riverbed is not covered by concrete, then

these works are performed right at the metal basin in order to secure the metal sheet piles and to

ensure tightness.

sheet pile with variable geometry 3

metal basin 2 sheet pile with variable geometry 2

concrete riverbed

sheet pile with variable geometry 1

Figure 6 Components of the metal basin 2

There must be a generator of electromagn

of the discharge sill in order for fish fauna

redirecting the ichthyofauna consists in a metal fence

the discharge sill (figure 7).

system for redirecting the

electromagnetic

metal basin 2

Figure 7 Positioning

There must be a generator of electromagnetic fields for redirecting the fish

fish fauna to reach the metal basin (figure 7). Another

consists in a metal fence fixed right into the river, d

system for redirecting the ichthyofauna

metal fence

for redirecting the ichthyofauna

c field

discharge sill

ositioning systems for redirecting the ichthyofauna

for redirecting the fish downstream

7). Another system for

right into the river, downstream of

ichthyofauna

ichthyofauna

When the metal sheet piles are folded, the ichthyofauna can easily reach the metal basin.

A basin made of galvanized sheet is fixed to the discharge sill. It is designed to supply

continuously the metal basin 2 located in the river (figure 8). The water supplying process

regarding the metal basin 2 made of galvanized sheet will be performed by using a cylindrical

pipe, which discharges water horizontally and it is fixed to the concrete plate.

discharge sill

metal dowels

basin fized to the discharge sill

sheet pile with variable geometry 3

sheet pile with variable geometry 1

water pipe supplying the metal basin 2

metal basin 2

Figure 8 Positioning the water pipe supplying the metal basin 2

A metal rectangular canal will be fixed to the discharge sill, near the left bank. The end of

the metal canal is fastened to a metal bar which, in turn, is mounted on two bearings (figure 9).

The bearings are mounted on a metal frame which, in turn, is fixed to the discharge sill.

metal bar metal rectangular canal

Figure 9 Positioning the metal canal on bearings

The canal is also mounted on a metal bar (support bar) which is fixed, in turn, to the left bank.

(figure 10).

metal rectangular canal

left bank

metal bar

discharge sill

electric motor

Figure 10 System for fastening the canal to the left bank

There is a space of about 5 cm between the left concrete river bed and the rectangular

canal so that the canal could get some variability in vertical plane. Sheet piles with variable

geometry are driven by an electric motor similar to the one in solution I previously presented,

which is placed under water and secured to the left

detection in the basin, and thus after detecting a n

geometry is automatically verticalized

from the upstream system. When folding (

will fit the rectangular canal into a crenel so that it is positioned

left bank

bearing metal grid

system

Figure 11 The system for fastening the upstream end of the rectangular canal for

fauna migration

water and secured to the left bank. There are sensors for

thus after detecting a number of copies, the sheet piles with variable

verticalized, that happens only if the system is working separately

from the upstream system. When folding (verticalizing) the sheet pile with variable geometry

ular canal into a crenel so that it is positioned on inclined plan

rectangular canal

left bank

grid

ystem for fastening the rectangular canal to the sheet pile 1

for fastening the upstream end of the rectangular canal for

for ichthyofauna

sheet piles with variable

if the system is working separately

variable geometry 1

(figure 11).

for fastening the rectangular canal to the sheet pile 1

for fastening the upstream end of the rectangular canal for fish

The rectangular canal for fish migration is almost full due to water supplying process

performed by the means of the pipe directly connected to the fixed basin and, therefore, to the

discharge sill. This pipe maintains a constant water level in the metal canal made of sheet piles

with variable geometry. The sheet pile with variable geometry 1 can be folded from the outside

towards the inside (vertically) as the other sheet piles, allowing the rectangular canal to be fixed

on the crenel in the sheet pile (figure 12).

rectangular canal

bearing

discharge sill sheet pile (basin 2)

Figure 12 The operation of the system for fish fauna migration

When closing the sheet pile presented by the solution I previously, it blocks fish

migration in the metal basin 1 located upstream of the discharge sill, the three sheet piles with

variable geometry of the metal basin 2 downstream of the discharge sill verticalize and prevent

fish from entering the basin. The connection between rectangular canal and the basin 2 facilitates

a safe migration of fish upstream of the discharge sill. The rectangular canal is composed of a

metal grid that does not allow fish to jump into the river, downstream of the discharge sill. The

electricity needed to run systems for fish migration upstream of the discharge sill may be wholly

or partially obtained from solar sources. Even if there are some discharge sills outside the cities

where there is no electricity and no concrete river beds, then such works should be performed in

the area (concrete riverbeds) so that the system can work as presented and then a solution can be

found in terms of energy source (electricity resulting from hydraulic energy, batteries or solar

power). The two systems can work independently especially when it comes about the mass

migration, such as salmon migration. Also, a single system can operate according to the direction

of fish migration upstream or downstream of the discharge sill. Likewise, one system of the two

presented before can be built because fish migrate upstream or downstream only, depending on

the river (hydro-technically arranged). In terms of current technology, the construction of these

modern systems for fish migration is not a complicated issue. They do not require a large

financial consumption and have the advantage that, once no longer useful in the area, they can be

reused for other rivers after minor modifications, as well.

All rights reserved Bucharest

2014