A map from the Council of the Haida Nation shows the two proposed cutblocks east of Tlaa Gaa Aawtlass/New Town. A hydrological study done last year by Statlu Environmental Consulting found that logging the two cutblocks would not increase the risk of flooding to the community, though further study would be needed if any more logging was planned in the five affected watersheds nearby.

Study found logging near New Town / Tlaa Gaa Aawtlaas would not increase flood risk

A study done last year found that logging two controversial cutblocks near Tlaa Gaa Aawtlaas/New Town would not increase the local risk of flooding.

The study found that logging the cutblock closest to the community would remove about a third of the trees from a small, 30-hectare watershed that drains into Masset Inlet through a stream running just south of the Tlaa Gaa Aawtlaas reserve.

But although the logging would likely cause a noticeable increase in the stream’s summer and winter flows, the study found it was unlikely to increase either the size or frequency of larger, potentially damaging floods.

“Harvest of the blocks will not increase flood hazard on the reserve,” wrote Drew Brayshaw, a senior hydrologist and geoscientist with Statlu Environmental Consulting.

BCTS No25-2016-Hydrologic Hazard Assessment DEL007 NAI001 by Andrew Hudson on Scribd

Using updated LiDAR mapping provided by the Council of the Haida Nation and fieldwork done by the Infinity-Pacific Stewardship Group, Brayshaw found there are five watersheds in the area, and existing provincial maps do not reliably show where they are or how they flow.

Of the five watersheds, Brayshaw found only the smallest, 30-hectare one would have a significant portion of its trees removed by logging of the two cutblocks in question.

However, Brayshaw also noted that logging has cumulative, non-linear effects on local water flows, so another flood-risk assessment would be needed if more cutblocks were planned in those watersheds.

Typically, Brayshaw said that logging 25 per cent or less of a watershed has a minimal impact, while logging 60 per cent or more results in more frequent and larger floods. Some of the factors include past logging, the rate at which trees are regrowing, canopy structure, storm size, as well as rainfall or snowmelt.

Brayshaw noted that the Masset area gets about 1,508 mm of rain and snow a year, with two-thirds of it falling between October and March. The extreme daily rainfall on record is 68 mm over 24 hours.

Just Posted

Decision time is coming for Masset schools

School board to decide soon whether to close Tahayghen Elementary School

Mount Moresby Adventure Camp aims to protect trails, ecosystems with expanded tenure

New tenure boundaries would also allow MMAC to rebuild lakeside dock for campers and general public

Signs of the Yakoun’s power

Shifting logs along the Golden Spruce Trail are almost certainly signs of powerful flooding

Court to rule on Husby injunction against protest at Collison Point

A B.C. Supreme Court judge will soon decide whether to grant an… Continue reading

North Coast teachers learn the language of technology

School District 52 teachers learned about circuits, Microbits and JavaScripts on April 20

How to keep local news visible in your Facebook feed

Facebook has changed the news feed to emphasize personal connections. You might see less news.

Dix says B.C. remains focused on fighting youth overdoses in wake of teen’s death

Elliot Eurchuk’s parents say he died at his Oak Bay home after taking street drugs

North Coast teachers learn the language of technology

School District 52 teachers learned about circuits, Microbits and JavaScripts on April 20

Final week for ALR input

Public consultation process closes April 30

‘When everybody leaves: Counselling key to help Humboldt move on after bus crash

Dealing with life after a tragedy can be the worst part following a loss

Half-naked shooter guns down four, runs away in Nashville Waffle House shooting

Nashville police say they are looking for Travis Reinking in connection with the shooting

Child’s body found in river downstream from where boy went missing during flood

Three-year-old Kaden Young was swept out of his mother’s arms in February

B.C. VIEWS: Eliminating efficiency for farm workers

Don’t worry, NDP says, the B.C. economy’s booming

Most Read