The RCMP say they have investigated nine cases of sexual assault at Manitoba Hydro's Keeyask generating station construction site in the last four years.

Of those cases, four resulted in men being charged with sexual assault. In the other reports, the victim declined to press charges or didn't want to take part in an investigation.

Gillam RCMP investigated one report of sexual assault in 2015, two in 2016, three in 2017 and three in 2018.

Grand Chief Garrison Settee of the Manitoba Keewatinowi Okimakanak — which represents Manitoba's northern First Nations — said he believes the number of sexual assaults at the work site is higher.

"A lot of people live in fear and don't want to come forward," Settee said.

"I think a lot of the cases have not been reported … because of fear of reprisal, or fear of repercussions."

This is a problem at the Keeyask construction camp right now and Hydro has to own it. - Peter Kulchyski , University of Manitoba

His group has been calling for more concrete measures to protect Indigenous women from sexual violence at the Keeyask site.

The 695-megawatt hydroelectric generating station is being developed 725 kilometres north of Winnipeg, in partnership between Manitoba Hydro and four First Nations: York Factory First Nation, War Lake First Nation, Tataskweyak Cree Nation and Fox Lake Cree Nation.

The four First Nations have demanded the province of Manitoba conduct a public inquiry into historical and current allegations of sexual violence, racism and discrimination at hydroelectric projects in Northern Manitoba.

A Clean Environment Commission report released in August 2018 detailed the social impacts of hydro development on surrounding communities, including abuse and racism as Hydro workers moved in.

'Numerous initiatives': Manitoba Hydro

A spokesperson for Manitoba Hydro said the Crown corporation would not comment on any RCMP investigations of sexual assault.

Bruce Owen said people charged by RCMP have had their site access to the Keeyask site revoked.

He said Manitoba Hydro has developed "numerous initiatives to combat these issues."

"We have also had extensive workplace standards in place that apply to all contractors and must be followed by all employees at site," he said.

Manitoba Hydro says it's providing tailored messaging and on-site training to combat discrimination and sexual violence at the Keeyask generation station construction site. (Manitoba Hydro)

Manitoba Hydro has on-site training around sexual exploitation, with "tailored messaging" for nurses, security personnel, and emergency medical services, as well as housekeeping, bartending and hospitality staff, he said.

"Efforts are also currently underway to develop broader communication materials for Keeyask," he said, adding that there's an existing on-site "respect" campaign that addresses concerns with harassment and discrimination.

Owen said Manitoba Hydro has also sponsored a concert with Robb Nash, who tackles bullying, addiction, and suicide prevention, and arranged a visit with the head of Winnipeg's Bear Clan citizen patrol.

Risk of potential assault ignored: prof

A researcher who warned that sexual assaults would happen at the site said Manitoba Hydro is doing the "bare minimum" to tackle the problem.

"I think the numbers are telling us it's not adequate," said Peter Kulchyski, a Native Studies professor at the University of Manitoba.

"This is a problem at the Keeyask construction camp right now and Hydro has to own it," he said, adding that there are likely more sexual assaults occurring than those reported.

"This is the tip of the iceberg."

Kulchyski spoke at the Manitoba Clean Environment Commission in 2013 before the dam was built.

"I actually warned the Environment Commission and Manitoba Hydro back when they were holding hearings into Keeyask that something needed to be done or there were going to be sexual assaults taking place," he said.

These kind of issues in the past have been ignored and shelved and not deemed as a priority. But it keeps resurfacing. - MKO Grand Chief Garrison Settee

He said his concerns were ignored.

"I felt like they weren't really taking the issue seriously or doing anything above and beyond doing cultural sensitivity training.… There's a giant, huge construction camp with guys coming from all around Canada, and from all around the world, who have no attachment to that place," he said.

According to the RCMP, the victims and the accused in the nine cases are from a variety of communities and cities across Manitoba, as well as from outside the province: one victim from Alberta and one accused was from British Columbia.

"The social conditions in these communities have absolutely nosedived since that camp has been placed so close to them," said Kulchyski.

"With the resources they have, the communities are doing the best they can to keep their heads above water."

Amnesty International plans to look into issues

Grand Chief Settee said his group wants a concrete commitment from Manitoba Hydro on how it will handle complaints of sexual assault.

"We have never been involved in this process when it comes to these complaints," he said.

The MKO is in talks with Amnesty International about the situation. The NGO confirmed to CBC News it plans to conduct research on racism, discrimination, harassment, and sexual violence against Indigenous people working on the projects.

A protester holds a sign at the legislature rally on Jan. 18. Representatives from the four First Nations involved in the Keeyask dam project say they've been dealing racism and sexual assault at the hands of Manitoba Hydro's workers. (CBC)

"These kind of issues in the past have been ignored and shelved and not deemed as a priority. But it keeps resurfacing," he said.

"Seventy-three per cent of northern Manitoba is First Nations," he said.

"Our involvement in any corporation is so minimal. I think we should have more of a say in what goes on."

4 First Nations 'not being taken seriously'

Those concerns are echoed by Nathan Neckoway, a band councillor with Tataskweyak Cree Nation.

Neckoway is a board member with the Keeyask Hydropower Limited Partnership, which overseas the project and represents Manitoba Hydro and the four First Nations involved.

"We as the Cree Nation Partners are not being listened to. We're not being taken seriously about what's happening within the project. Racism, harassment, discrimination, even assaults, are happening at all levels within the project," he said.

"We as a First Nation have been telling the Hydro corporation that these contractors need to address this from the first day it occurs," Neckoway said

"We do not want to tolerate this anymore. This dam is in year four of construction, and it's impacting our people."