It’s a little hard to make out the houses in aerial photographs of the 1997 flood in south Yuba County. Only after a minute or two do we realize that we are not looking at floating detritus, but at the rooftops of homes nearly submerged in the brown water.

At least one person died in that flood, which destroyed 180 homes and businesses while damaging another 480 structures. The ground, according to a local news account at the time, was “littered with the carcasses of hundreds of drowned farm animals.” The price tag on the damage was $200 million, according to the state Office of Emergency Services. No stranger to high water, south Yuba County had been inundated previously in 1986 and 1955 during floods that took more lives and damaged far more property than the 1997 version.

In the same flood zone, a group of 22 developers, including KB Home and Lennar, is currently proposing to accelerate home building. Surprisingly, the efforts to build in a flood-prone area are being supported by a public agency – the Three Rivers Levee Improvement Authority. The rationale is that a home building fee is expected to fund at least $135 million of a levee strengthening project in south Yuba County estimated to cost $230 million-plus. The project may also qualify for some of Proposition 1E’s $4.1 billion in flood control bonds, although that is not certain.

While some strong arguments can be made for the strategy of using home building as a means of paying for critically needed levee repair, some danger remains that new homes in the area could be damaged or destroyed if a flood occurs before the levees are fixed. And that danger raises serious moral issues with the scheme: Is it worthwhile to put a comparative few homes (and lives) at risk in the interest of providing flood control at a faster pace than would otherwise occur?

The setting of this precariously balanced moral dilemma is the Plumas Lake specific plan area, a 5,200-acre portion of unincorporated Yuba County just south of Olivehurst and the junction of State Routes 70 and 65. Although the specific plan has existed since 1993, home building has only recently heated up with the suburbanization of greater Sacramento. The housing product is affordably priced starter homes. With pleasant views of rivers and farmland, the houses hold particular appeal to both retirees and middle-income public employees who work in the capital city 40 miles south.

During the early years of the decade, the state Reclamation Board – the body responsible for overseeing California’s levees – and the home builders were butting heads. In 2003, the home builders agreed to pay upfront $28 million, the original estimated cost of levee repairs, in advance of the work, in return for permission to build. At that time, the home builders planned on reimbursing themselves with an assessment district.

By early 2005, however, cost estimates of levee work had swollen to $110 million. About half that money could be supplied from a Proposition 13 grant. The state Reclamation Board looked to the home builders for the rest. On this occasion, the home builders agreed to charge levee fees of $29,345 per house. Although that sum may seem high, it is close to fees paid by many home builders in more urban locales.

The money would go to the Three Rivers Levee Improvement Authority, a joint powers authority composed of Yuba County and Reclamation District 784. Perhaps as a way of hedging its bets, the Reclamation Board limited home building to 800 units a year in 2005 and 700 units the following year. (The specific plan allows 11,740 dwelling units in all; about 2,600 have been built.)

Earlier this year, yet another increase in costs torpedoed the 2005 plan. The flood control costs reached an estimated $230 million. The builders had the unpalatable choice of increasing levee fees threefold, which would have made the homes too expensive for the “starter” market, or the public agency would have to wait an additional six or seven years to complete the levee work – an invitation to disaster. Representatives of the levee authority argued vigorously for the Reclamation Board to lift the building caps as a means to generate levee-repair funds quickly. Although individual board members expressed misgivings, the board agreed to remove the cap in April of this year.

In approving the plan to accelerate housing development, the Reclamation Board was aware it was gambling. But it was a calculated risk, according to Scott Shapiro, a Sacramento-based lawyer who is special counsel for the levee authority. As part of the agreement, the home builders assented to a number of “mitigations,” including a more vigorous effort to inform existing and potential homeowners about flood risks, and providing every new home owner with flood insurance. The authority also agreed to assist in creating new evacuation plans reflecting studies of those areas most likely to flood first in the event of a breach. In addition, the levee authority stepped up its efforts to improve some of the most vulnerable stretches of Yuba River levee system, which are scheduled to be upgraded this winter.

“There is no question that there is a window of danger,” Shapiro said. “In the balance, do we put a small, additional group of people at risk in exchange for getting everybody out of risk faster?”

“On a risk-analysis table,” Shapiro continued, “you actually pose risk to fewer people, for a shorter period of time.”

I don’t know what a professional ethicist would say, but I actually find Shapiro’s argument compelling, even though there is something troublesome in my willingness to endanger the few (even if those dangers are low) in the interest of the many. As one of the Reclamation Board members mordantly observed earlier this year, flood insurance does not cover loss of life.

“Between the intention and the act,” wrote a famous poet, “lies the shadow.” In a similar way, between the acts of building a house and finishing a levee, a flood may lie.