Another example, from Jamaica. Rainfall in June 2003 was in excess of 1000
mm in 3-4 days. Ground water level responded with a rise of more than 40 m,
with ground water flooding in some places roads, houses, etc. However, the
subsurface there is composed of fractured limestone (The White Limestone
Formation), with an average effective porosity not more than 3%. It is easy
to calculate that the rainfall of 1 m with such a porosity could locally
produce the rise of levels between 30 and 40 m. The recession was much
slower due to low transmissivity of the limestone. Land (ground surface) is
of course composed of very permeable limestone formations with not too much
surface runoff.

======================
Dr. Jasminko Karanjac, Consultant Hydrogeologist & Professor (ret.)
e-mail: karanjac@...
tel. +381-11-163983 +381-64-311-0304 (cel)
www.geocities.com/karanjac

----- Original Message -----
From: "harindranath harindranath" <cs_hari@...>
To: <gwrm@...>
Sent: Thursday, December 22, 2005 7:16 AM
Subject: Re: [gwrm] Sudden rise of GWLevel


> This years rainfall in Bangalore has created the raise in the vadose
> ground water level. Earlier the GWT was around 10 to 20 meters BGL when
> there were open wells. Now a days the GWT has gone done to more than 30 to
> 40 meters in Bangalore. Last month one of my friends garage was flooded
> due to the raise in GWT of his bore well and several cases has been
> reported. However it was a temporary phenomenon.
>
> Hari
> KSRSAC Bangalore
>
>
> S V Vijayakumar <vkumarsv@...> wrote:
>
> Dear all,
>
> Recently, I have come across some fine data in a sand stone formation
> where a large canal is under construction. Here, it is observed that
>
> 1. the groundwater level rose by about 18 metres from September to
> Novemeber (post monsoon seson) in two increments seperated by a week. This
> has not been experienced since 2002.
> 2. The ground level is about + 45 m and The water level rose from -13 m to
> + 5 m above mean sea level.
> 2. The previous year's high was about 8 m below the present high. Both
> highs occur with in a week after end of rainfall event.
> 3.Previously, when ever a gap of one week in rainfall is there, there was
> recession in levels, where as now the recession limb is not falling like
> that and daily pumping fluctuations in water levels were not so visible as
> they were earlier. This seasons rainfall is about 50% more than that of
> last year, which recorded normal rainfall.
>
> I want to know from group that can any one specify such a rise elsewhere
> and the plausible reason? reference of any reports on such studies.
>
> V Kumar