For decades, Sacramento's Pocket neighborhood has offered thousands of homeowners an idyllic lifestyle along a broad bend of the Sacramento River. A few hundred riverfront homeowners enjoy additional pleasures thanks to backyards that reach across the levee, with private access to the river.

This unique lifestyle may be changing, however, amid more stringent state and federal efforts to protect Sacramento from catastrophic floods.

In short, some of those waterfront backyards may have gone a few feet too far. Some backyard structures – swimming pools, sheds, retaining walls and fences – interfere with levee maintenance and may threaten levee stability.

Considered "encroachments" under the law of flood control, they create weak points, engineers say, in the levee itself, a public structure that protects every Sacramentan. Encroachments have been a problem for decades, but in the wake of Hurricane Katrina in New Orleans they're getting renewed attention.

"We've got close to maybe a dozen, maybe two dozen swimming pools either too close to the levee or actually encroaching on the levee itself," said Len Marino, chief engineer at the Central Valley Flood Protection Board, a state agency. "It's a mess. We have to somehow deal with that."

In August, citing encroachments, the U.S. Army Corps of Engineers ruled that most levees in Sacramento failed maintenance inspections, including those on the south bank of the American River. Encroaching structures, it said, prevent access for levee inspections and stand in the way of battling seepage, erosion or a levee break.

The ruling was not just symbolic. It eliminated Sacramento's access to millions of dollars in federal disaster funds to rebuild levees in the event of a flood. This is an unprecedented and worrisome event for a city with a flood danger recognized as second-worst in the nation – after only New Orleans.

"That's like a great big insurance policy backed up by the full faith and credit of the federal government," said Marino. "We feel it's important to get it back."

He said the flood board plans to send the Army Corps a letter of intent this fall to comply with the encroachment rules. If accepted, this would restore eligibility for the federal funding program and give the region two years to correct the encroachments.

This could require radical changes in those backyards, a prospect that is unsettling to Pocket homeowners.

"It would be devastating if they made us pull the pool," said Bob Herr, a Pocket homeowner who has a sparkling blue swimming pool next to the levee. "I'm sure it would affect property values. There'll be a lot of lawsuits."

Herr doesn't know if his pool poses an encroachment problem. It may be a close call.

He bought his home 10 years ago, with the pool in place. He heard stories that the design of the pool was changed at the last minute, as a result of an inspection, because it was too close to the levee. The shape of the pool bears this out: It is gracefully curved along its entire edge, except next to the levee, where it looks like a curve in the pool was amputated in a straight line to follow the easement.

"That was probably three owners ago," Herr said. "All this was here when we moved in."

His neighbor Shirley Short also has a pool near the base of the levee. Hers may be far enough away, but her back fence could pose a problem. Unlike Herr's chain-link fence, Short's is built of wooden planks that do not allow visual inspection of the levee.

Permit rules tightened

State and federal officials disagree about another type of encroachment: trees growing on levees. The Army Corps maintains that trees threaten levee stability and wants them removed. The state disputes this and hopes to defer action on levee trees until a compromise is reached.

In contrast, there is little disagreement that structural encroachments are a problem.

Dave Brent, director of the city Department of Utilities, said Sacramento tightened its permitting rules for structures near levees in the wake of Hurricane Katrina – just as the Army Corps and the state tightened their own flood-control rules.

When the city general plan was updated about six years ago, he said, it required a 50-foot building setback from any levee, far more than what was required when the Pocket was developed in the 1970s.

In addition, Brent said, any homeowner seeking a permit to build a pool near a levee now must get approval from the Central Valley Flood Protection Board. This was not required before the general plan update, Brent said, so it's possible many pools were built out of compliance with flood board rules.

"The mindset was different back then," Brent said. "They built these levees to allow development. And once they had levees in, people were like, 'OK, we're good.' "

The Pocket and Little Pocket neighborhoods share a unique history of property rights and flood protection that complicates the problem. Unlike virtually all other levees in Sacramento, those south of Sutterville Road have a patchwork of legal easements that complicate levee maintenance and access.

In actions going back to the 1920s, state and federal agencies did not always obtain full access easements to the levees. Some property owners retained a right of exclusive access over the levee to the Sacramento River. As a result, public access to the levee is now severed by more than a dozen locked fences.

Most property deeds do include a flood control easement, ensuring that levee maintenance agencies have legal rights to preclude structures along a width of at least 10 feet at the base of the levee. But many property owners over the decades either didn't know this, or ignored it and built structures in the easement anyway.

In some cases, there are swimming pools dug 10 feet deep at the base of the levee.

"That's a pretty serious example of an encroachment that has multiple problems," said Rick Poeppelman, chief of engineering at the Sacramento District of the Army Corps. "It not only creates a problem for access, you're also removing material from the land side of the levee, so it becomes a stability problem and a seepage problem."

Multiple parts to problem

Even with two years to fix encroachments, the number and complexity of the conflicts make for a daunting task. So politicians are starting to weigh in on the issue in hopes of avoiding major effects on property owners. Rep. Doris Matsui, D-Sacramento, in August persuaded an assistant secretary of the Army Corps to send emissaries from Washington, D.C., to look at the Pocket's encroachment problems firsthand.

"Clearly, over the last several decades, the process has broken down," Matsui said. "Ultimately, the Corps needs to be a partner with local agencies for a solution to this, and I believe they will be."

Swimming pools are the most obvious encroachment, but not the most numerous. A 2010 inspection of all metro-area levees found 580 encroachments. Of these, 30 percent were buildings, 24 percent were fences, and 17 percent were pipes or culverts, according to the Army Corps. Less than 1 percent were pools or ponds.

Even the 10-foot easement, where it has been heeded, may prove inadequate. The easement was acquired in an earlier era, without forethought to a time when levees might have to be enlarged to contain deeper floods or seepage. Today the Army Corps prefers a 20-foot easement.

Engineers now understand that many Sacramento levees are vulnerable to seepage, because they were built of sand and other porous materials dredged from the river bottom early in the 1900s. Impervious seepage walls can be built inside levees to deal with this problem, and some have been built in the Pocket.

But deeper seepage walls may be necessary.

And there is also the need to accommodate larger floods. A California law passed in the wake of Hurricane Katrina made it state policy to achieve 200-year flood protection in urban areas. This, along with climate change, may require taller, wider levees.

There is little room to widen levees in the Pocket.

"It's a big unknown what's going to happen next," said Councilman Darrell Fong, who has lived in the Pocket for 30 years. "Some of it's out of our control. I'm just urging people to be very careful, because this is a very sensitive issue. People get very upset about it."

Property conflicts likely

An Army Corps study expected to be unveiled in June, called a general re-evaluation report, will recommend significant structural improvements to Pocket-area levees, said David McDaniel, a branch chief at the Corps. The necessary fixes have not been finalized, but they could include more conflicts with private property.

McDaniel, however, said the Corps is ready to be flexible.

"They absolutely need some kind of work," he said of the Pocket-area levees. "There's not a one-size-fits-all answer. We would be looking at solutions that would possibly require less of a footprint to deal with the seepage and stability and minimize the need for access."

One option could be an engineered retaining wall on the land side of the levee. It would have a stout foundation excavated into the base of the levee, providing seepage control and room for maintenance.

The Central Valley Flood Protection Board is the agency charged with policing encroachments. In recent years, it has been far more consistent about preventing the kind of conflicts now plaguing the Pocket.

In January 2011, for example, the board rejected a request from a property owner to build fences across the levee on both ends of his 500-foot-long parcel. It did so even though the owner hired a platoon of attorneys and consultants and pursued the project for three years.

The 14 existing fences blocking Pocket-area levees are permitted because the landowners retained rights to limit access. They are not considered encroachments, and flood control agencies have access through them.

These fences may soon be targeted by the city of Sacramento, however, which wants to open the levees for public recreation. Prompted by interest from City Council members, the Parks and Recreation Department in November expects to bring forward proposals for opening up these levees.

This would likely require the city to acquire access easements from property owners.

"We would all lose all of our privacy if people were able to cycle and walk and take their horses along the trail behind our homes," said Short, who has lived along the levee for 15 years. "That would not be a good deal. I would move, probably."

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