Puntledge River diversion dam – linked to larger version
Located about 3.7 kilometres downstream of the Comox Lake Impoundment Dam, the Diversion Dam is where water is diverted from the Puntledge river into a pipeline that travels five kilometres to the BC Hydro’s Puntledge Generating Station and back into the river.
That same water also goes to the Puntledge Hatchery, and the water supply system for Courtenay and Comox.
But how does it work?
The Diversion Dam is a 30.5 long concrete buttressed structure with a crest elevation of 133.2 m, connected to the 20-ha Puntledge Head Pond. Outflow from the Head Pond to the penstock is controlled by two 5.23 m wide x 4.14 m high sluice gates. The sill elevation of the sluice gates is 125.12 m. The overflow spillway from the Head Pond is a three-section compound weir at 130.2 m (76.2 m long), 130.29 m (9.1 m long) and 130.38 m (30.5 m long) elevations. The normal operating water level of the Head Pond varies between 129.9 m and 130.2 m.
Source BC Hydro
In simpler terms, the diversion dam diverts the Puntledge toward the intakes for the penstock pipeline.
Water that is not sent down the penstock pipeline flows over the top of the spillway (and the diversion dam during floods) and downstream in the Puntledge.
Salmon are screened out and then safely deposited back in the Puntledge, downstream of the dam and penstock inlet system.
and now you know