That Awful Limitations Vortex

That Awful Limitations Vortex

By Paul Collar

 Paul is a hydrogeologist and environmental engineer and the owner/operator of Osa Water Works.  You may reach him at

Sometimes only a well will do.  Many Osa homes are beyond the reach of Acueductos or rural Asadas.  Many more don’t have a spring on their land, and even if there is a small quebrada, well water is higher quality and less maintenance.  And, given Costa Rica’s insistence on a concession for building permits (see last article here), a well is often nearly a no-brainer.

Sometimes only a bored well will do.

Just drill it right?   That’s what we’d do in many parts of the world.  But this is not many parts of the world.  The Costa Rican regulatory criteria for a drilling permit are pretty strict.  And without a valid drilling permit, you are precluded from applying for a concession once the well is drilled.  It’s very important to have a drilling permit before actually drilling.

Many of my friends, and even I, tend to scoff at “requirements.”  And even though a driller runs the risk of rig confiscation for drilling without a permit, many will still do it since enforcement is lax.  Better to “ask forgiveness after the fact than permission before,” the theory goes.  Only, not in this case; the requirement of a valid drilling permit as a prerequisite to concession application is rigidly enforced.  Even if you don’t need a building permit, just water, you should still do it the right way.  If you are not able to concession your well and then later put your property on the market, you can’t boast about your great well since it will be illegal; rather than a property feature, it’s more of a bug to creatively dodge during due diligence.

The drilling permit is a bureaucratic tangle, three-six months of waiting, and carries a cost of $1250 if things go swimmingly, more if you are caught within the limitations vortex.  But even if you are delayed and forced to pony up for supplemental studies, you’re sure to land your permit in the end.  Let’s review first that limitations vortex and examine worst-case scenarios.

There are three circumstances which trigger further studies before SENARA (Servicio Nacional de Aguas Subterraneas, Riego, y Avenamiento) will sign off on the technical viability of the well being proposed:

  • Coastal proximity. For locations less than one km from the coastline, a salt-water intrusion study is required to show that the proposed well will not result in contamination of the aquifer with sea water.  Salt-water intrusion occurs where near-coastal pumping draws deeper salt water upwards to contaminate an otherwise potable aquifer.  This is a valid concern.  For every meter of water table drawdown beneath sea level in near coastal lands, the salt-water interface rises FORTY-fold.  So Costa Rica is right in protecting the coastal integrity of fresh ground water supplies through this supplemental requirement, one that adds around $1500 to the drilling permit cost if you are caught in this wide-spread vortex.


Salt-water intrusion: For every meter a well’s cone of depression drops below sea level, the salt water interface is expected to rise by 40 meters

    • Well Interference. If you drill a well close to an existing well, it is intuitive that neither well will produce the same as if the other were not there.  Costa Rica establishes a “minimum” separation between wells of 100 meters.  If you must drill a well within 100 meters of an existing well—at least a registered, legal well—this triggers a well-interference study in which your geologist will determine how to achieve an exemption, based on either geological findings or operational limits to minimize interference effects.  Budget $1000 for this study if you are caught in this minor vortex, relatively rare still outside of highly populated areas.

Well-interference: Costa Rica establishes a 100 meter separation between production wells. If you are less than that distance from an existing well, a well-interference study is required to demonstrate the proposed well is sustainable and won’t affect the neighboring well’s production


    • Offset.  The most controversial limit on drilling locations, the most insidious of the three limitations vortices, is the 40-meter offset required from property boundaries, public roads, and structures.  A 40-meter offset means, for instance that no property less than one-half hectare in size qualifies for a well, since a perfect circle with a 40 meter radius is equal to 5,024 square meters.  Because of irregular boundaries, it is rare for even one hectare properties to have a single spot within property boundaries eligible for a well.  Houses are often built close to roads,

    This 1.3 hectare property is 300 meters from the coast, triggering a salt-water intrusion. A 40-meter radius circle is super-inscribed to show that no portion of the property falls outside the offset vortex. We’re only 5 meters off, but Senara rejected the first round application, insisting that we comply with a trip down the offset rabbit hole.

    So even larger properties may not be able to drill a well in a good spot owing to this restriction.  Lastly, a well is often intended to serve a home and having to position the well 40 meters away from the home adds capital and operating costs that are often frustrating to homeowners.  The rationale behind the offset is to protect the well from pollution from septic tanks, spills on highways, or from activities on adjacent properties beyond the applicant’s control.  While proactive in a nanny-state way, it is commonly a trigger for a well-drilling permit rejection.  That said, SENARA will permit the offset distance to be reduced to as little as 15 meters if it can be shown through percolation tests and/or granulometry and permeability measures that infiltration is slow enough that contaminants are biodegraded before reaching the well intake zone.  Currently a flash-point of national blow-back against Senara, expect the old fixed-radius exemption vortex to set you back another $1000 in special studies.  For longer term water-law watchers, expect the offset rules to be rolled back at the regulatory level in the next couple of years.

    Welcome to the make-believe alternate universe of the offset limitations vortex.
  • When none of the preceding limitations apply, budget $1250 for a drilling permit and three-six months of time.  If you are in Tamarindo and aspire to drill a well, you’ll face all three limitations, so budget $4500 in permitting costs and then expect to be declined.  There are circumstances in which it is perhaps more prudent to sink that money into a rainfall capture system and save the headache of trying to justify your way through a perfect constellation of vortices.

    The drilling permit, like all other permits, requires all that legal jazz:  cédula jurídica, personería, copy of applicant ID, signatures, notarization, powers of attorney where required, plano catastrado, all corporate and property taxes and fees up to date.  But beyond that the drilling permit is unlike many other permit applications in that it requires THREE legally authenticated signatories on the application.  Not only must the owner / applicant’s signature appear but also that of the geologist and driller, all three signatures notarized.

    Drilling companies turn out to be the incidental market beneficiaries of this system and typically steward permits after inking drilling contracts.  But a land-owner is not beholden to this model and may steward his or her permit without being contractually bound up front to a single driller.  And a valid permit in hand allows market forces to favor the landowner in a drilling contract negotiation.

    In order to move from a finished well to a concession, here are the things that you have to have:

    • A valid drilling permit.
    • A complete well.
    • A geological report prepared by the driller
    • A 72-hour pump test prepared by the driller
    Hand dug well finished with OWW steel pump base mount and automation, ready to put the lid on and walk away.

    The notable exception, one that is enjoying a predictable renaissance in sight of its wormhole around vortices, is the humble, often-maligned, but ever reliable hand-dug well.  In Costa Rica, you do NOT need a permit for a hand-dug well.  And you are not required to obtain concessions for hand-dug wells but merely inscribe them as wells with Senara in order to qualify for residential building permits.  Since this automatically eliminates problems associated with coastal proximity, well interference, and offset rules, this option has major upsides for those locations where it is an option.  Near surface groundwater is more susceptible to septic tank contamination, livestock, and non-point source pollutants.  Its practical limit is around 10 meters of depth and rarely costs more than $2-5000 to complete.  It’s an option mostly restricted to near-coastal and alluvial flood plains along rivers and at the foot of mountains.  Still, that includes 25 % of the Osa Peninsula and pretty much the entire Pacific and Atlantic coastlines of the country as well, and many places inland.

  • Most deep Costa Rican aquifers are in fractured volcanic rocks, and well productivity is hit and miss.  You need to hit a fracture swarm for really good production.  Areas that are not extensively fractured are tight and water poor.  Zones of lower transmissivity or that include sedimentary layers with high organic content can suffer from high iron and manganese, sometimes even hydrogen sulfide.  These are bad luck wells and treatment alternatives for high iron and sulfur are costly and often unsatisfactory.  Still, the likelihood of hitting good water even blindly is unusually high in Costa Rica, and bored wells are typically reliable and bountiful solutions for remote residential water supply.

    If you need a well, to do it right takes six months at least in lead time, more if you are flirting with the limitations vortex.  But if you rush things and don’t do it right, then you can’t legitimate that well down the line.  It’s pretty easy to do it right and doesn’t have to be overly costly.  But it helps to first throw yourself against the learning curve.


    See the original article here

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