A County Government Perspective Julia Fonseca

Pima County, Arizona is a medium-sized While floodplain regulations don't protect Western county where only 25% of the land is riparian habitats, land acquisition can. Many privately held. Uke many Western counties, counties in the West have vigorously opposed private land is often found along the larger federal land purchases, particularly along floodplains. Many of the towns in Pima streams. But Pima County has supported fed County, including Tucson, originated along eral acquisition of floodplains on a variety of these floodplains. Since 1974, federal regula grounds. We think that keeping floodplains tions have set the framework for how Pima natural upstream of Tucson makes sense. County manages floodplain development. Why? Because broad, well-vegetated flood plains act somewhat like dams. They slow Since the floodplain regulations went into down the velocity of water and allow floods effect, the population in the unincorporated to spread out harmlessly on undeveloped County has tripled in size, and a great deal of public land before hitting downstream urban the riparian habitat that was in the floodplain areas. Ifthe upper watersheds were channel has been lost to housing, businesses and road ized, flood peaks downstream would in ways. That rapid growth has sparked the de crease. Upper watersheds also recharge the sire among environmental and neighborhood urban aquifer downstream-an ecosystem ser groups to see riparian habitat preserved dur vice that often goes unrecognized. In addi ing development. These groups often believe tion, Pima County residents seem to like the that we floodplain managers can prevent recreation and natural open space that public floodplains from being developed, and hence land can provide. protect streamside vegetation This just isn't so. We only specify how floodplains may be For example, Pima County tried to muster modified. We can't prevent anyone from re up millions of dollars to buy the 75,000 acre locating or modifying the channel ifit's done Empire Ranch, located upstream of Tucson. is a manner that won't directly affect adjacent The Empire Ranch has one of Pima County's properties. And of course, we can't prevent few perennial streams and is home to the Gila anyone from remOving riparian vegetation Topminnow, an endangered fish. In 1987, from his property. Anamax (a large mining corporation) began

From my perspective both as hydrologist and as resident of Tucson, existing floodplain regulations have not protected riparian habi Julia Fonseca is a hydrologist with the tat. Federal and local floodplain policy state Pima County Flood Control Districtin ments may seem to encourage preservation, Tucson, Arizona. Ms. Fonseca received J but actual floodplain regulations don't give us her MS in geology from the University of those powers. That's why last year we tried Arizona. Since 1986, she has overseen to amend our local floodplain management the management and protection of the ordinance to require mitigation of riparian District's riparian habitat preserves. She habitat losses due to development in the has also helped develop a wide variety floodplain. Our County Board did not sup of land use policies, ordinances and port the amendment, but directed us to ex flood control programs designed to plore placing regulations in the zoning code. protect riparian habitat.

22 to market this land for "ranchette" oped land. About a thousand acres of development. When the County failed to mesquite bosques, cottonwood-willow for strike a deal with Anamax, our Board of Su ests, and xeroriparian habitat have been ac pervisors got the Congressional delegation in quired specifically to protect these plant com volved; the result was that the BLM acquired munities. For instance, we purchased a rare the Empire Ranch through a land exchange. desert marshland and its associated mesquite We're now working with _------_ forest along the San Pedro the BLM to encourage River. This area, known as them to acquire additional #In some areas, we've Bingham Swamp, is man- riparian land. found that it's cheaper to buy aged for us by the Nature floodprone structures than it is Conservancy. It lies adja- Pima County has its to build levees and excavate cent to other lands along the own acquisition program, channels to protect them." San Pedro River that the which has been very suc BLM hopes to purchase. cessful in preventing or Another is located just removing development in floodplains. We downstream of the Empire Ranch along have spent $34 million buying flood and ero Oenega Creek. sion- prone land along seven principal water courses. Acquisitions have been financed Together with the BLM Empire Ranch through two bond elections and a secondary trade, we've brought over thirty miles of tax on real property. In some areas, we've Oenega Creek into public ownership. And found that it's cheaper to buy floodprone . we have taken our management responsibili structures than it is to build levees and exca ties for these natural areas very seriously: we vate channels to protect them. have reduced or eliminated off-road vehicular access and grazing along these areas, and Acquisition of floodplain property is an have filed for instream flows. innovative technique of proven effectiveness in reducing flood losses. Purchased areas We don't just buy perennial streams; more provide natural flood storage which reduces often we purchase ephemeral streams with flood peaks downstream. One District study limited streamside vegetation. You have to estimated flood-peaks would increase 40% if understand that in our community, the trails upstream floodplains were developed using that are used by both wildlife and people are conventional structural flood-control mea in dry streambeds, and there's a big constitu sures. Increased erosion of channel beds and ency that sees value in bringing watercourses, banks resulting from structural flood-control even dry ones, into public ownership. That projects can also be lessened by establishing constituency comes into play during some areas where natural erosion processes can zoning issues, with the result that the devel continue unabated. oper sometimes turns natural areas along the channels over to the County. Pima County's acquisition program has been a locally-initiated effort; it got started in Federal agencies, acting through the Sec 1984, following a series of four Presidentially tion 404 of the Clean Water Act, have been declared flood disasters in Tucson. (We just important in encouraging acquisition, by pro had a fifth one this January.) These floods viding legal and financial disincentives for have taught us that federal disaster relief ef levees and channels. Although it wasn't the forts are slow and cumbersome. Also, federal main intent, Section 404 mitigation require relocation programs won't pay to relocate ments have doubled the cost of flood control those who don't suffer damage, but are clear structures. Section 404 hasn't stopped a single ly at risk from future flooding or erosion. project of ours but has certainly provided us And federal programs won't usually pay to incentives to avoid riparian habitat losses. acquire undeveloped land either. Another way Section 404 has helped save ri parian areas is through restricting dredging of One of the unusual features of our acqui channels to remove sediment and vegetation sition program is that we can buy undevel-

23 For instance, we've created a wonderful To sum up, I'd say that the federal gov riparian habitat by discharging effluent into ernment would have a hard time encouraging the Santa Cruz River. It's a great place for riparian habitat protection measures in an un birds and local bird-watchers. But the willing local community. On the other hand, vegetation sustained by the effluent also helps there's no end to what communities can ac to clog the channel, so some of the floodplain complish through good local leadership, even farmers downstream want us to remove the if no consensus exists. It's important to recog plants. Again, the main reason it hasn't been nize that Pima County's accomplishments done is Section 404. On the other hand, other have occurred in a community which has sections of the Clean Water Act that regulate been and still is divided on issues like the use the quality of effluent may force us to dry up of public funds for acquiring and managing this habitat by diverting the effluent to other of riparian lands. uses.