Sondalp's innovations for the environment and the worker's safety on structure maintenance

  • Innovation 1  : Our acidification packer with pneumatic support
  • Innovation 2 : Our acification cleaner with pneumatic support
  • Innovation 3 : Our filtration and grit removal unit

Better be safe than sorry ! Opt for a preemptive maintenance and a diagnosis of your structures to prevent any production break and avoid heavy investment.

SONDALP's offer :

In situ diagnosis

You wish to assert your catchment’s structural engineering quality, as regular safety checks or in the event of a productivity loss:

  • assert your structure’s conformity,
  • detect possible abnormalities : casing hole, deposit, clogging’s nature…
  • identify the cause of a flow rate loss.

Our 2 mobile workshops, self-sufficent energy wise, allow for the realization of televised inspections, physico-chemicals loggings, current-meter, gamma-ray, caliper, cementing control…
You will know everything about your well, all the way down to 500m !

Please be aware about your country’s regulation on water wells, as mandatory controls might be necessary.

This operation might require for the pump to be put down for at most a day. A detailed report will be delivered to you. 

Televised inspection

The televised inspection allows to visualize the entirety of the structure and to detect any abnormalites, in order to:

  • Ensure state : corrosion, perforation, collapse, grit deposit, clogging
  • Detect the nature of corrosion
  • Detect the clogging type : mineral, biological in order to know the best way to treat it
  • detect objects in the structure


Loggings are an inspection allowing to :

  • Measure and record the physical or chemophysical values in a drilling, according to depth:  Redox potential, pH, Electrical conductivity, Dissolved oxygen,
  • Identify any water with a different nature coming into your structure by reading the contrasts in temperature and conductivity,
  • Check the water arrival areas and measure the proportions, percentage of the flow rate produce in the drilling per part (current-meter and flow logging),
  • Cementing control with  CBL Cement Bound Logging and pipe’s adhesion to the concrete,
  • Control of the diameter to certify the sections’ diameter on all of the drilling’s height,
  • Control of the clay-content : determine if the clogging is linked with the presence of clay or situate in a geological section : gamma ray

Execution of pumping tests

We undertake pumping tests, linked or not with the production of one of our drilling : stages, long-span.
Our hydrogeologists take action in order to set up, watch and read into the pumping tests necessary for a full comprehension of the water tables and structures.

We have at our disposal :

  • 1 stock of over 20 pumps, from 3 to 14 inch, for a capacity from 3 to 600 m³/h
  • + 1 kilometre of flexible or rigid pipes
  • 6 impulsion electromagnetic flowmeters with continous record of flow and turbidity
  • a multitude of pressure sensors
  • d’ appareils de mesure physico-chimique in situ performants : température, pH, conductivité potentiel d’oxydo-réduction, fer, manganèse, nitrate, dureté de l’eau…

Maintenance and regeneration

Catchment work are under heavy solicitation while pumping  and grow old at different rates. Regular maintenance work allow to slow down the ageing process and extend the lifespan of a structure.

In order to do so, we provide you with:

  • The execution of pumping tests before and after regeneration as to specify the restored structure’s new hydraulic behaviour and the treatment’s effectiveness, with full disclosure.
  • The regeneration of a structure by mechanical treatment (brushing, jetting, shockwave hydropuls® process, airlift ,…) and/or chemical (acidification, disinfection)
  • A televised inspection of the work upon receipt
  • Other services if needed (retrieval, wellhead and structure repair)

Mechanical regeneration

  • Chemicals use reduction: safer for the workforce and environmental friendly
  • No water neutralization
  • Intervention time reduction

It functions by brushing in order to have the deposit drop and swabbing to remove whatever is clogging the ground’s porosity.

As a complementary option, in certain cases, SONDALP uses the  Hydropuls® innovative process : it allows for a in-depth treatment of the water table surrounding the strucutre. By the sudden and repeated expansion of an highly compressed inert gas, we generate hydraulic shockwaves. These cause the finegrained fractions, mineral deposits, etc.,  contained in the suction strainer’s openings as well as in the gravel pack  and the water table to disaggregate.

Chemical regeneration

For certain pathologies, it is necessary to go for a chemical regeneration, for instance in case of:

  • Mineral clogging: carbonates, iron oxides, manganese involving dissolution with an acid
  • Bacterial problems: involving rinsing with a chlorine solution

These recovery works are realized under high precautionary principle for both staff and the environment and are accompanied by a detailed report.

Drains cleaning
Nettoyage de drains
Before-After : strainer and pump
Avant-Après : crépine et pompe
Hydropuls process efficiency
Efficacité du procédé Hydropuls
Specific flow and treatment
Débit spécifique et traitement

Rehabilitation and refilling

In case of structural disorder, we can carry out a rehabilitation by rechecking of all or part of the solid or screened tube, according to the pre-established diagnosis.

In case of permanent abandonment of the structure, the regulation requires that refilling is adhered by the rules of the trade, which implies the reconstitution of the naturally impermeable zones in cement grout, and the filling of the aquifer zones with an inert porous formation (sands, gravels).

The abandonment of a borehole is suitable when:

  • The borehole is old, with too much damage to be repaired
  • The ground reservoirs are polluted
  • The commune is fed with water differently and no longer uses the borehole
  • The cost of a new borehole+abandonment is inferior to the cost of rehabilitation

Maintenance program

The average lifespan of a drilling is 40 to 50 years. In many cases, no fund is budgeted to maintain the drilling. Curative maintenance is expensive and sometimes involves blocking production. Preventive maintenance anticipates these problems and allows to:

  • follow the work in real time
  • anticipate the cleaning of boreholes to make it simpler and shorter
  • prevent any production break
  • avoid heavy investments in case of substantial work by smoothing reconditioning prices over the duration of the subscription

SONDALP is able to commit and provide you with a maintenance program : you entrust us with your drilling, we upgrade it and we give it to you with the same performance 10 years later, with proof to show for it!

Benefits of the maintenance program

  • Peace of mind
  • Improvement and maintenance : water quality and production rate garanty
  • One sole responsability source : transfer of the exploitation risk over to SONDALP : garanty on the pumping equipment, increase of the lifespan and of the state of the well knowledge
  • Financial predictability : stable annual fees and reduction in pumping costs via a betterment of energetical efficiency