TL: DR : RGV/SPI will grow north out necessity, Politics are changing in S.Texas, Desal and 2nd Causeway Federally funded. I believe the second causeway will happen (and will fight for it politically). A few reasons: Politics, SpaceX, Growing North Across the RGV.
As I have posted on this thread before, I have spoke with Carlos Cascos (former Cameron County Judge/Former TX Secretary of State/signed the SpaceX deal) about this subject, and he stated it is all politics at the state level. South Texas votes Dem and Texas is a Rep state. As simple as that when it comes to funding this and dragging it out. He said this causeway could have been done decades years ago if the politics were different....are they changing now? Me thinks yes!
Enter illegal immigration and politics. I was born in 1987 and have been going to SPI my entire life. Lived in Weslaco, Harlingen, Laguna Vista, and SPI until we realized we couldn't raise a family on SPI during the Spring break and Summer. We are currently trying to move back to Laguna Vista, again, and it has been interesting hearing the opinions of the "locals." The entire RGV has suffered the consequences of unchecked illegal immigration, but the tide is turning now.
Enter SpaceX, my family along with 1,000s of others now watch rockets launch from SPI. My children know my beach growing up as the place we watch rockets launch (and blow up!) while fishing and eating tacos. There are now regularly 1,000s if not 10,000s, from around the world, of people fascinated by what is occurring down there. As well as the employees of SpaceX, most new individuals to the RGV don't want to live in Brownsville...they have told me. This is a whole new population of people that will have generational impact.
My realtor was talking about the gentrification of the local colonias (Laguna Heights), and how residents that have been renting their entire lives, there, are being priced out due to SpaceX and LNG workers coming in now.
I don't know SPI in the 80s, but I have seen pictures of Spring Break, MTV, etc. and the demographics (and waist sizes) have certainly changed over the years. I spent high school Spring Break going to SPI, and my father (from Indiana) talked about SPI for years as a attractive venue for snow birds, northerners, and winter Texans (depending on the Canadian dollar). I spoke with the Mayor of SPI at the time (Barry) and he stated that 75% of the owners on SPI are retired folks. I just talked to a couple retiring from the BCS, and they looked at SPI but said there was not enough activities for retired folks there...they went to Arizona instead. Go figure.
Nobody in PI or SPI (that I know of) wants the second causeway (or SpaceX for that matter), because it will kill the South side of the island. It will become "old SPI" and will force PI and LF to lose business and tax revenue. I will say it has been incredible to watch Los Fresnos grow over the last 20 years due to the traffic going to SPI. It is clear that the SPI development of the Convention Center, Claytons, Hilton, and all of the "North Side" amenities were built there with the hope of growing north.
But on to new business! Politics are changing in the RGV (I am staking my political career on that) and the growth cannot be contained. All of the major cities have no where to go except North encroaching on the smaller cities. I live in College Station right now, and never thought I would see CS get so close to Snook and Navasota, but here we are. I even hear talk at the council meetings about merging BCS into one city! Never say never! Cities like Lyford, Harlingen, Rio Hondo, Primera, Edinburg, Mercedes, La Feria, etc. all growing North...there is no where else to go.
So finally, I think SPI will growth north because it has no other choice. For the first time ever, I heard that Port Aransas was the hot spot for Spring Break this year! (I know it was in the past). But with SpaceX, Valley growth, and a global population of people finding out about the gem that is SPI, there is no other logical conclusion IMHO.
...As for water, that is a problem for everyone in the 956, now. Population growth, business growth, closing of the sugar mill, a lot of people are now just waking up to realize they will need more water. As I have stated in my campaign, I am for using federal funding to support desalinization plants as well as the 2nd causeway. Those are two critical infrastructure projects that South Texas deserves!
"Suppose you were an idiot. And suppose you were a member of Congress. But I repeat myself."