flow_regime.md

hydrology/flow_regime.md
> SYNTHETIC TEST DATA - NOT FOR USE IN ANY REAL ASSESSMENT
> Generated by the ESIA governance sandbox. Fictional geography.
> tenant=meridian project=kanjeza domain=hydropower tier=clean seed=7

# Flow Regime, Sediment and Cumulative Setting

*Discipline: hydrology_and_sediment | Tenant: Meridian Environmental Partners | Register refs: PS1-08, PS6-24, HYDRO-SED*

## Naturalised regime

Mean annual flow is 74.2 m3/s with a pronounced
seasonal signal. The Q95 low flow is 16.4 m3/s. The
reservoir has a surface area of 48.3 km2 at full
supply level behind a 74 m structure.

## Operating rule

The proposed operating rule provides a continuous compensation release of
6.0 m3/s. This value is set by firm energy
optimisation.
An environmental flow assessment establishes a requirement of
12.4 m3/s. The operating rule has been
revised to meet it and the commitment is carried into the ESMP.


## Sediment

Incoming load is 3.1 Mt/yr at an estimated trap
efficiency of 92 per cent, implying downstream
sediment starvation and progressive incision.

## Levels and datum

Foundation and abutment levels are reported in MVD-72 (national).
Inundation extent has been modelled on the global geoid and
the 2.3 m offset applied throughout; the affected
settlement list is derived from the corrected surface.

## Cumulative setting

Schemes considered: the upstream weir, the proposed
irrigation offtake, and the downstream scheme in advanced planning, which
shares the regulated flow regime.