The court heard that Waters did try to persuade the victim to attend group sessions but she declined, and after conferring with his wife, the sessions went ahead.
It was the second training when the incidents took place in the woman's lounge.
They involved the victim placed in positions where Waters would touch her genitalia or breasts, or get her to touch him on his genitals.
The fact Waters was a policeman, and married, made her feel safe with him, the victim said while reading out her victim impact statement at a previous court appearance.
"When you said you were a police officer that also gave me a feeling of trust and confidence that I could trust and confide in you and I never once considered that you would overstep your [professional] and personal boundaries which would leave me feeling vulnerable."
She wanted help rebuilding her confidence and physical strength.
"I sought professional advice and assistance from you to help build my confidence, personal fitness and core strength to support my back. This was and still is important to me.
"You understood some experiences I had in the past and I felt confident at that stage you knew what you were talking about."
Waters touched the woman's genitalia four times and simulated sexual intercourse during a martial arts training session at her house.
As the offending occurred at her home it had left her feeling "paralysed" by fear, the woman said.
"I was forced to live in the very area where you assaulted me.
"The actions of you taking your trousers off make me question my own decision-making about trusting people."
She had spent the past two years in specialised counselling.
The offending had also left her visibly bruised over her body.
"My sternum took weeks to resolve and was excruciatingly painful."
She said she had suffered hugely after the assaults, from anxiety, lack of sleep, and also by having to sell her home where the offending occurred.
Crown prosecutor Duncan McWilliam said home detention monitoring wasn't available as a sentencing option due to "technical reasons".
Waters' counsel Phil Morgan QC stuck to his original submission that the offending only warranted a sentence of community work, saddled with an emotional harm reparation payment of $1000.
Judge Nevin Dawson acknowledged Waters' previous clean record and 30 years' working as a police officer.
He said a key factor was holding the former cop accountable to the harm he had caused the victim which had been "profound".
However, the consequences of his actions had also affected Waters too.
"You've lost your good name, your good record, and your reputation in the community," Judge Dawson said. "You also lose the job that have had for the last 30 years and lose your income ... your ability to be able to train people ... is also now questionable."
The judge also ordered Waters to attend a course for sexual offenders and any other counselling as directed by his probation officer.
Outside court, the victim said she would donate the $1000 reparation to Cambridge police who she thanked for their professionalism while dealing with the case.
She was disappointed by the sentence but was relieved that it was all over.
Waters' estranged family were also at the sentencing and said they were disappointed they had to find out about the case in the media.
A family member said her biggest disappointment was how her brother didn't admit what happened or show any remorse to the victim.
A Police spokesperson last night said that Waters remained suspended on pay while he was the "subject of an ongoing employment investigation in relation to his off duty behaviour".
"As employment matters are a private and confidential matter between the employer and the employee. We are unable to comment further at this time."