Environmental Assessment
Volume C-3.6
Slurry Pipeline
Hydrology
Ambatovy Project
53
January 2006
The Key Questions for the hydrology surrounding the slurry pipeline are:
Key Question H-1
What Effect Will the Slurry Pipeline Have on
Flows and Water Levels in Water Bodies?
Key Question H-2
What Effect Will the Slurry Pipeline Have on
Sediment Levels in Water Bodies?
3.6.4
Impact Assessment
3.6.4.1 Impact Pathway Evaluation
As shown by the surface water hydrology linkage diagram in Volume H,
Appendix 9, project activities during pipeline construction may result in the
following: i) changes in flows and water levels in receiving water bodies; and
ii) changes in sediment levels. These changes may occur along the pipeline
right-of-way, at watercourse crossing locations as a result of disturbance to the
streambed during construction, and due to water withdrawal and disposal
associated with pipeline hydrostatic testing.
Changes in flows and water levels, in conjunction with changes in sediment
supply, may also affect channel morphology as the channel attempts to reach new
equilibrium conditions.
Changes in flows, water levels and sediment levels in receiving water bodies may
also affect water quality, fish and aquatic resources, socioeconomics and land
use. Water users are described in the socioeconomic and land use baseline
reports (Volume K, Appendices 1.1 and 3.1) and effects of hydrologic changes
on water users are described in the socioeconomic and land use EA reports
(Volume C, Sections 5.1 and 5.3).
3.6.4.2 Assessment Methods
Changes in flows, water levels and sediment levels in receiving streams were
evaluated based on a qualitative evaluation of proposed mitigation, stream
hydrologic characteristics, and construction techniques.
3.6.4.3 Impact Description Criteria
The assessment criteria used for hydrology are presented in Table 3.6-4.
