River degradation may result as an environmental impact of riverine mining (quarrying). In the case of the lahar-inundated Pasig-Potrero River, the alleged degradation due to lahar quarrying has not yet been established, resulting in contrasting claims and weak policy formulation. This study investigates the presence of environmental degradation in the Pasig-Potrero River by obtaining the induced extraction rate of river sediments against its natural replenishment rate through the use of modified erosion poles. Subsequently, a description of the river`s geomorphological behavior in response to its sediment mobility performance was made. The twelve-week observation recorded a deficit sediment supply of around 337,023.04 cubic meters from upstream mountain ridges as against the quarrying production rate. The extraction rate is 246 times faster than the ability of the river to replenish new sediment material. Quarrying controls the river`s physical environmental health at 56.94% level. Thus, the river is experiencing intensive erosion due to sediment over-extraction.
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