Vasluiet river restoration!

1. Vasluiet River on the outskirts of Vaslui
The first ecotechnical method
Ph.D Razvan Voicu
rzvnvoicu@yahoo.com
Vasluiet River is polluted with organic substances coming from the wastewater
treatment plant of the city of Vaslui. We must find solutions for wastewater treatment.
One solution would be the FLOATING GRIDS. This floating grid can be made of
bamboo or any other material and has a metal waterproof outer frame. The outer frame is
fastened to some bars fixed in the bank of the river, which, in turn are provided with a
fixing system of grids so that they can slide according to the water level.(fig.1).
streambank
metal frame
floating elements
metal bars fixed in the riverbed
floating elements
plastic bearings
metal bars fixed in the riverbed
metal bars supporting the floating grid
Figure 1 Solution for wastewater treatment

2. This grid of floating elements should support the floating plants called Eichhornia
Crassipes (Water Hyacinth), Pista Stratiotes (Nile Cabbage) having excellent depolluting
functions. These aquatic plants successfully carry out their depolluting functions between
15 and 34 degrees. Therefore, they should be covered if any continuous operation in a
channel or pond is necessary.
The technology used involves the use of aquatic plant species, active links of food
chains, which are characterized by bioconversion processes and bioaccumulation.
If appropriate, harvested biomass, after performing the physico-chemical and
biological analysis, is directed to various fields such as: adjuvant in animal feeding,
extraction of pigments, retention in methane fermentation, achieving a germinating bed
for rehabilitating the degraded land, formation of silos with straw. There were obtained
good results using these aquatic plants in our country. Plants are placed into the
rectangles of the floating grid; they grow up and will soon form a floating carpet for
water purification (fig.2).
floating grid
Figure 2 Water purification system
On the entire length of river channel Vasluiet having about 600 feet, minimum 20
floating grids of 10 meters length shall be made in order to purify plenty of water in this

3. river sector. These floating grids will be up to ten meters in order to be lifted with a
special crane, unloaded, put back with the amount of plants required. To run all year, this
riverbed sector should be covered by a cupola made of glass or transparent plastic that
allows plants to receive the necessary light. Temperature must not fall below 15 degrees.
External opening windows in the cupola must be made for ventilation. During the winter
heating should be placed inside the dome. Also, cupola (Fig.3) must be equipped with
multiple doors where staff can enter to collect plants, as the process of lifting the grating
with the crane is no longer viable in winter. Cupola must be removable for the warm
period.
external opening windows
cupola for plants operation
floating elements
metal bars attached to bed
Figure 3 Way to plant winter operation
A chart of energy costs consumed during winter, but also of damages caused by
pollutants must be made, and according to these the construction of cupola, which works
in winter, will be decided.

4. The second method
Consolidation method regarding the banks of Bârlad River in the village of Stefan
cel Mare, Vaslui County. There are detachable sections of Bârlad riversides in the village
of Stefan cel Mare, therefore there is risk of falling into the river blocking the water
course(fig.1,fig. 2).
Bârlad River
the displacement of the left bank
Figure 1
Bârlad River
the displacement of the left bank
Figure 2
For both cases of dislocation of banks, a reliable ecotechnical method was
developed.

5. Methods for Verticalization and Inclined Planes
For its stability, the bank must be verticalized up to the cracking from the inside
and then, from the same point, an inclined plane to the river Bârlad must be executed (fig.
3 si fig.4).
cracking in the riber bank
Bârlad River
Figure 3 The current status of the Bârlad river's banks in the village of Stefan cel
Mare
wooden sheet-piles
dowels
Bârlad River
riparian
vegetation
Figure 4 Ecotechnical method for reconstructing the left bank of the Bârlad river
in the village of Stefan cel Mare

6. The verticalized area will be strengthened by wood piling secured by durable
plastic dowels, and various plants, including trees (alder, acacia, etc.) will be planted on
the inclined plane in order to stabilize the river bank. The works will be carried out by the
means of some mechanized equipment. On both areas characterized by sliding sides, the
same type of work will be carried out.
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Bucharest
2011