The government's announcement on how £2.3 billion will be spent on flood defence in England is not enough to stem the risk of future flooding, according to the CLA.
But Defra said homes and businesses 'will be better protected', including an economic boost to areas through regeneration.
"Floods can devastate our communities, which is why I have fast-tracked the delivery of the £90 million Boston barrier, as well as nearly £150 million across the region to protect thousands of homes and businesses," said Danny Alexander, the Chief Secretary to the Treasury.
"Investing £2.3 billion to support 1,400 schemes across the country will protect 300,000 homes from the north-east to the south-west. As well as ensuring people’s safety and peace of mind it will also bring over £30 billion of economic benefit, making it great value for money as part of this government’s drive for a stronger economy and a fairer society."
Environment Secretary Elizabeth Truss said: "Flood protection is vital and under our plans Lincolnshire and Northamptonshire will be better protected by 89 schemes being delivered across the region, including the Boston Barrier and Humber schemes, which will bring peace of mind to residents and businesses.
"We are spending £3.2 billion in flood management and defences over the course of this parliament - half a billion pounds more than in the previous parliament. This, combined with the record level of investment in capital we have set out today, will improve protection to 465,000 homes and businesses by the end of the decade."
Environment Agency Chairman Sir Philip Dilley said: "Our priority is to do as much as we can with every pound of funding from government and local partners, we now expect to provide better flood protection to an additional 300,000 properties in England by the end of the decade.
"With one in six homes in England at risk of flooding, and recognising the risk of flooding can never be eliminated, we would also encourage people to take their own steps to prepare for flooding, for example by signing up to the Environment Agency’s free flood warning service.
"This first ever long-term investment programme will protect thousands of properties around the UK and save the national economy £2.7 billion by 2021. The lifetime benefits of this investment will be even higher at over £30bn. New schemes may also be added as the programme progresses."
Since the beginning of this parliament flood defence investment has improved protection to over 230,000 homes and over 580,000 acres of land in England. This new investment will protect at least another 300,000 homes by the end of the decade.
But CLA President Henry Robinson said: "One year on from devastating floods, communities and businesses across rural England are still alarmingly vulnerable.
“It is worrying that the £2.3billion allocated has already been defined as “inadequate” by the National Audit Office. Funding must be part of a broader strategy that provides genuine reassurance that the risk of flooding is being tackled comprehensively.”
Mr Robinson said landowners can play a vital role in shoring up flood defences but they are currently restricted by expensive environmental surveys and permits as well as having to coordinate with a multitude of agencies.
He said: “CLA members are playing a critical role defending land and communities against flooding. However, the Government and the Environment Agency must make it easier for landowners by cutting red tape and encouraging new, effective approaches to managing drainage. Without this support we risk losing valuable agricultural land, homes and communities.”
