The environmental impact of the two underground alignment options for the Cross Island Line (CRL) can be “adequately managed” with comprehensive mitigating measures and monitoring plans.

Read more at https://www.todayonline.com/singapore/cross-island-line-environmental-impact-can-be-adequately-managed-both-alignment-options

alternative reporting on Straits Times:

The future Cross Island MRT line that will run from Tuas to Changi can either run under the Central Catchment Nature Reserve or go around it.

https://www.straitstimes.com/singapore/transport/feasible-for-cross-island-line-to-run-through-central-catchment-or-skirt-around