The initial $80,000 in damages were recovered from insurers, but Guerra say they have since declined to cover him.
When he complained to the council, he was warned in a draft letter in May: "The council strongly urges you to take immediate steps to remedy the unauthorised and unconsented works carried on your property."
Flooding problems, the council said, were caused by:
• Doing earthworks in an overland flow path without resource consent;
• Removing a scruffy dome or open drain pipe in the ground - structures so big they are covered with wire cages for safety reasons - and replacing that with a manhole cover;
• Building a retaining wall in that overland flow path without consent;
• The retaining wall being more than 1.5m high, therefore needed building consent which wasn't applied for or granted;
• Building a concrete courtyard area which contravenes the building code and needed building consent.
The council indicated Guerra was to blame for most of that because the work was not completed with all the relevant consents and plans and did not fully comply.
Connections had been made to the reticulated system, so there was nothing wrong with the neighbouring works, the council said.
The Council also told him he would have to rectify the issue. Legal advice was that it was unlawful for the council to allow the works on Guerra's property to remain unconsented so he had to act, he was told in May.
Council also warned all the problems at his property would be listed on his Land Information Memorandum - so that if he tried to sell, potential buyers would realise the illegal nature of his works, it said.
Yet, Guerra stresses he is not at fault because there were no issues until the neighbouring land was developed. Now, even in moderately heavy rain, "water gushes over the retaining wall, overwhelming the drains in our courtyard and entering our house."
He claims he did not need consent to build his wall or courtyard and said some relief had occurred since March when new drainage was installed next door.
Guerra says the scruffy dome on his property was removed by a council worker in 2016 because "it was too dangerous for animals and kids. The council put a lid on the drain."
Complaints to the council's compliance team several times asking for assistance resulted in the compliance investigator attributing the flooding to a section of retaining wall which he claimed was non-compliant, Guerra said.
"He attempted to impose a fine but this was withdrawn as our professional engineer had met all the council's requirements," he said.
Guerra then tried to get the council to write a letter so he could get his house insurance reinstated with AMI but the council said it had taken legal advice and decided that was not appropriate. Guerra claimed he did not need consent for his retaining wall or courtyard and his engineer advised him he did not need any consent.
The reviewing solicitor then noted all the illegal works at Guerra's property.
"Since March 15, we have not been flooded. I don't have to do any work to my property because by putting in the drain above, it's been resolved," he said today.
But he remains unhappy about all the trouble, saying: "We want the council to write a letter so we get insurance again and they haven't done that."
A council spokesperson said:
"We have been corresponding with Mr Guerra for a number of years, including taking enforcement action relating to an illegal retaining wall on the property. We are however continuing to work with him to resolve his concerns about the neighbouring development."