Across the gulf, Houston and the state of Texas are coping with the aftermath of Hurricane Harvey. A natural disaster like this keeps me up at night. A storm both torrential and unending, gathering strength in the warm gulf waters and making landfall directly on our shores would devastate Tampa.
The fear of this reality is only tempered by the extent of preparation that we achieve. One year ago, we made a commitment to address our flooding issues by establishing a new stormwater improvement assessment. Thanks to the hard work of our public works team and the wisdom of the Tampa City Council, this $251 million program provides infrastructure and improvements to mitigate flooding in our most vulnerable areas. From Sulphur Springs to South Tampa, across West Tampa, East Tampa and the university area, we are on the ground preparing for the day Tampa is the target of a hurricane or unceasing storm.
It is never easy to ask our residents to pay more, but when we do ask more of them I know they expect more from us. In the last year, we have begun or completed nearly $125 million of the $251 million in planned projects — half of the total program we committed to at the start.
The stormwater service assessment that passed two years ago is paying for Tampa's stormwater staff and contractors to clean ditches, outfalls and ponds and other stormwater facilities that have been neglected for decades. Some outfalls were nearly 100 percent blocked with barnacles, oysters, toys, leaves, muck, silt, plastic bags and even vintage soda bottles. Our 100-year-old system has never been cleaner, but much work remains. We have removed and disposed of more than 50,000 tons of material clogging our system, much of it by hand.
Tampa has proactively invested tens of millions of dollars in our wastewater system to reduce sewage overflows.
We have upgraded our largest pumping station located in downtown Tampa. We are cleaning our largest interceptor, which serves about one-third of Tampa, and built in reserve capacity at the Advanced Wastewater Treatment Plant so that it can handle as much as 221 million gallons per day during storm events. Additionally, in the last five years, the city has rehabilitated over 34 miles of pipelines and 1,900 manholes to reduce leakage in our wastewater system.
Unfortunately, like all older wastewater utilities in our country, we must do much more. This was demonstrated just days ago as extremely heavy rains led to untreated wastewater spilling into the Hillsborough River. Each time we experience this type of failure, we go back to the operation of every one of our 230 pump stations to guarantee we managed the situation to the best of our ability, learning lessons from any incident.
Those lessons propel us forward to implement new solutions. The city is advancing plans to replace the 1950s' Harbour Island Force Main, a $25 million investment. We are exploring and working on the initial engineering of a way to divert wastewater to the Central Intercepting System, a future $10 million project. Finally, we will continue to invest in pipeline and manhole rehabilitation to work on sealing our wastewater collection system for stormwater and groundwater infiltration and inflow.
There is much more work to be done, and every day we are making progress. By means of our geography, we will always be vulnerable. Tampa receives approximately 50 inches of rainfall per year, most of it in a five-month period. We could accept the fact that every city has its turn, and eventually Tampa's years of escaping the wrath of a natural disaster will come to end. But that is not who we are as Tampanians. When we see a problem, we find solutions.
Last year, I asked Tampa to invest in preparing this city for our worst nightmare. Each and every resident, Tampa City Council, business leaders and your team at the city of Tampa stepped up in a big way and today we are better off for it. There is no time to slow our efforts when each day that passes it becomes more likely that the work we are doing will be put to the test. Thank you for preparing with me. Now, let's get back to work.
Bob Buckhorn is mayor of Tampa.