Messenger: CRZ 2019 and ‘removal’ of sandbars: An incongruous amendment

Jan 12, 2022 | 05:52 IST

CRZ 2019 and ‘removal’ of sandbars: An incongruous amendment

Antonio Mascarenhas

The Coastal Regulation Zone (CRZ) 2019 is not yet in force, although it was validated two years ago. Although acclaimed as a single piece of legislation, our authorities seem eternally dissatisfied with the ecological benefits it offers and the ecosystem services it provides to coastal beneficiaries. Since its inception in 1991, the CRZ laws have been repeatedly decimated by the release of a series of amendments over the past 30 years. The latest (draft) amendment, dated November 1, 2021, deals with (among other things) the removal of sandbanks in CRZ areas. Although the state of Goa has a valid but sketchy policy on river sand mining, the imposition of yet another amendment puts coastal conservation at grave risk.

In a new draft notification dated 1 November 2021, the MoEF has proposed further changes in the Coastal Regulatory Area Notification 2019 with respect to the removal of sandbars in CRZ areas as described in section 8 of the project. In paragraph 10, after clause 10.3, the following paragraph is inserted: “10.4 Removal of sand banks in CRZ areas: Sand banks in intertidal zones shall be removed by traditional coastal communities only by manual method (c mechanized canoes or small craft using baskets/buckets by human beings) in various coastal states. The state government may authorize such sand removal within a specified period of time in a particular area with a specific amount subject to conditions such as registration of persons in the local community authorized to remove sand manually and shall be removed on an annual basis”.

There is no reason why the new draft amendment emphasizes “removal” of sandbanks rather than “mining” or “extraction” of excess sand offshore or in estuaries. This question deserves scientific reflection. The term removal would mean complete removal of the sand bar and disposal of sediment elsewhere, while mining would mean systematic extraction of sand based on established guidelines. In addition, disturbing the formation or the stability of a natural sandy body likely to form under water is necessarily likely to have deleterious consequences on the morphology of the seabed and marine life in particular. The notification failed to address, but rather evaded, issues of ecological significance.

Sandbanks are by definition offshore, permanently submerged or partially exposed, but are mostly identified at the mouths of rivers as linear elongated spits. Brought to the ocean by rivers, sand deposits are redistributed under the action of waves, tides and currents. The geological setting of the region largely controls the sand and gravel depositional environments along the coast and in the rivers of Goa. Based on our field data, several sites with significant sand content can be identified: (1) Sand spits at river mouths occur at Tiracol, Chapora, Sal, Talpona and Galgibaga and are characterized by large accumulations of sand in the form of elongated arrows; the sand brought by the rivers and discharged into the sea is then transported by the long coastal currents and the coastal drift. (2) Sandbanks in estuaries are widely exposed at low tide at Chapora in particular, Sal, Talpona, Galgibaga and Maxem; the coarse sediments brought by the rivers are discharged into the estuaries. (3) Sand around islands in rivers is a major element around several islands which has increased in size over the decades. (4) Sand deposits along the riverbeds due to deposition and accretion are observed along the axis/central parts of the riverbeds; the sedimentary load transported and descended from the hinterland constitutes these accumulations. (5) River gravels and cobbles are found in the rocky regions upstream. (6) Sandy beaches and dunes are exclusively composed of unconsolidated loose sand. However, as the new amendment refers only to sandbanks, it is therefore presumed to refer exclusively to spits.

The geological significance of the arrows should be well understood. We need to confirm whether arrows should be removed or mined, which ones to consider first, how much sand to extract, and whether sand removal should be done periodically or continuously. The extraction of river sand is a regulated activity and therefore requires an in-depth scientific study or an EIA. In Goa, there is no science-based sand mining policy. News reports indicate that the NIO conducted specific surveys of sand deposition in river systems, but the results and content of the report, intended for the public good and the wise use of coastal resources, remained secret.

In summary, (1) Sand spits at the mouths of rivers are Nature’s playgrounds because these features belong to the ocean realm; being highly dynamic, these geomorphological features constantly change shape and location in space and time; thus, any human intervention on such fragile estuarine ecosystems is bound to prove counter-productive. (2) There is no guarantee that new sand will not return to the coast, given the high wave activity associated with the monsoon; moreover, the annual river flow carries sand in abundance. (3) Instead, the sand spit can be managed by simple and environmentally friendly methods; spindle growth can be limited at will. (4) It is important to note that sand extracted from a spit must be returned to the beach to which it rightfully belongs. (5) Given several unfavorable cases, a new equilibrium may never be reached if this area is disturbed. Unforeseen interference in an ever-changing spindle system will cause more harm than good. Therefore, a robust boom management system that involves training which in turn requires the extraction of excess sand is essential.

(Dr Antonio Mascarenhas is a former scientist, NIO, Goa)

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