Lake Tikitapu

Lake Tikitapu is a small, flat-bed lake formed by a lava dam around 13,000 years ago. Fed by rainwater and small surface flows, the lake has no surface outlet, but is thought to have groundwater flow towards Lake Tarawera.

Lake Tikitapu’s catchment is almost all native bush and forestry. The main source of human nutrient inputs is from the motor camp, public amenities, and people using the lake for recreation. Rotorua District Council intends to reticulate these amenities to remove these nutrient inflows.

Action Plan Status:  Working party to be initiated
Quality Now:  3.2 TLI
Quality Goal:  2.7 TLI

While Lake Tikitapu’s Trophic Level Index (TLI) has been relatively stable for the last four years, the TLI is substantially above its level during the mid-1990s.  An increase in phosphorus levels, a decrease in dissolved oxygen concentrations during lake water stratification and a decline in the extent of native lakebed vegetation are all concerning.  They warn that lake water quality decline in the future is likely.

• Wastewater reticulation and pipe out of the catchment.
• P-flocculants.

Further research should help narrow down the causes of lake water quality decline and offer some solutions. Possibly removing wastewater from the catchment and applying a flocculant to remove excess phosphorus from the water column could halt the decline and start to improve water quality.