Chapte 3 THE ALAMEDA COUNTY FLOOD CONTROL DSTRCT SEASONAL WETLANDS N UNON CTY: A QUESTON OF ACTON Alex Battaglia " ntoduction The south San Fancisco Bay and its magins ae chaacteized by shallow wate, educed tidal flushing, boad tidal flats, extensive salt evapoation ponds and small pockets of seasonal wetland. The seasonal wetlands ae found along the im of the Bay and ae distinguished by flooding in the winte and desiccation in the summe. Migatoy watefowl and shoebids pefe these wetlands fo esting and feeding, and ae and endangeed bids and mammals ae found in them as well, yet these wetlands ae disappeaing. t is estimated that 77 pecent of the pivately-owned seasonal wetland in Alameda County, south of and including the Oakland Aipot, has been distubed o destoyed since 1983 (Kelly, 1986, pes. i i - comm.). The Alameda County Flood Contol Distict (ACFCD) owns 600 aces of land in west Union City appoxi mately fou miles fom the Bay (Figue 1), 380 aces of which ae seasonal wetland. ACFCD's pimay function is stom wate management, and it uses pats of this seasonal wetland aea as stom wate flood basins. ACFCD also plans to use some of its wetland fo the dumping of dedge spoils; this poposal, if implemented, would affect habitat values at the dump site. Some land stewadship agency with expeience in management fo habitat values should administe the land in Union City along with ACFCD. f this was done, the land could povide a valuable combination of eceational, educational and utilitaian functions. t could seve as a pak o a peseve yea-ound and continue to offe flood potection duing majo stom peiods. Futue maintenance of the land's habitat values would be assued. Neaby Coyote Hills is successfully managed as a combined pak and flood basin aea by E3RPD and ACFCD; a clealy applicable pecedent has been set. The pupose of this pape is to highlight the biological and legal easons why ACFCD's land should be made into a pak o a peseve that could continue to opeate as a flood basin aea. The poposal, if adopted, would benefit not only people; it would also potect a wide ange of plant and animal species that depend on the apidly disappeaing seasonal wetland habitat. Souces of nfomation The biological infomation pesented in this pape is pased on seveal pio studies. A epot by Havey and othes (1977) outlines the unique functions of seasonal wetlands in the Bay Aea, lists the - 131 -
- 132 - Figue 1. Location and Aceages of Alameda County Flood Contol Distict Lands in Union City. Souces: Mille, 1986; Base Map fom Newak, Califonia Quandangle, 7.5 Minute Seies (USGS). plants and animals that ae found in them and povides data on the locations in the Bay Aea whee ae and endangeed species can be found. Onduff (1974) summaizes the types of plants that gow in the seasonal wetlands of Califonia. J.D. Pessle (1973) descibes the plants found in neaby Coyote Hills Regional Pak; these ae vey simila to those found on ACFCD's land. The specific infomation found in this pape on ACFCD and its land in Union City was eceived though pesonal communications. Paul Kelly and Roge Campbell povided geneal infomation on ACFCD's functions and its land. Paul Kelly also povided data on endangeed species found on the land. D. Howad Cogswell, Kaen Mille and Tei Pencovic shaed infomation on plant distibution and bid populations at the sites. Tei Pencovic also supplied legal infomation that petains to the study aea. Methodology Afte obtaining plant, bid and mammal data though libay eseach and pesonal communication, moe data wee gatheed by taveling to the study site and taking field notes on plant distibution. This involved diving along the levees which un though the aea, stopping evey 100 yads and then obseving the pedominant species in that location. These data wee used to map the diffeent plant
- - 133 - communities on ACFCD's land and to detemine if any aeas have been degaded. Knowledge of the plant communities and the ae and endangeed species pesent allowed detemination of envionmental egulations which apply to the study site. These lines of evidence povided a basis fo poposing that ACFCD convet the site into a pak o a peseve that also opeates as a seies of flood basins. Results The migatoy watefowl, mash bids and shoebids which have been sighted on ACFCD's land ae listed in Table 1. The aeas whee the endangeed salt mash havest mouse (Reithodontomys aviventis) Mash Bids Watefowl Shoebids Othe Watebids * Pied Billed Mallad Ameican White ' Least Ten* Gebe Gadwall Pelican Foste's Ten Ameican Bitten Double Cested Nothen Pintail Comoant Geat Eget Cinnamon Teal Ameican Avocet Ruddy Duck Blacknecked Nothen Stilt Shovele Semipalmated Ameican Widgeon Plove Ring Necked Duck Buffiehead Soa* Black-bellied Plove Mabled Godwit Whimbel Geate Yellowleas * Rae Visito Table 1. Migatoy Wate Bids Found in the Study Aea. Souces: Cogswell, 1986; Pencovic, 1986. has been found ae shown in Figue 2 (Kelly, 1986, pes. comm.; Havey, 1977). The site whee ACFCD has poposed the dump dedge spoils is shown in this figue as well (Kelly, 1986, pes. comm.). The plant communities found on the ACFCD land ae mapped in Figue 3. The salt mashland is dominated by pickle weed (Saliconia viginica), codgass (Soatina foliosa), and saltgass (Distichlis spicata), wheeas the ipaian aeas contain seveal wil.ow species (Salix), box elde (Ace negundo califonicum) and sycamoe (Platanus acemosa). The agicultual aeas, whee cabbage is gown, ae also shown along with two sites which ae distinguished by bald spots. These two pacels ae temed degaded, this tem being used to descibe those lands which had vegetation that has since been emoved o distubed by machiney.
- 134 - Poposed decge spoil site Figue 2. Salt Mash Havest Mouse Habitat and Poposed Dedge Spoil Site. Souces: Kelly, 1986; Havey, 1977; Base Map fom Newak, Califonia Quadangle, 7.5 Minute Seies (USGS) Discussion Salt mashland makes up 65 pecent of ACFCD's land in Union City (Mille, 1986, pes. comm.). ACFCD uses these salt mash aeas as flood basins (Campbell, 1986, pes. comm.). This pactice has seveal useful functions. t saves taxpaye expenses by utilizing a natual stoage aea fo stom wates that does not need to be maintained. t helps ceate a highe feshwate table in the gound since the stom wate stands in the basins fo extended peiods of time. This impoves the salinity baie fo the wells on ACFCD's land (Kelly, 1986, pes. comm.). Finally, flooding aids in the assimi lation of pollutants by the mashland that would othewise flow staight into San Fancisco Bay. This is because polluted wate is cleansed as it sits in the basins (Havey, 1977). Though much of ACFCD's Union City land is healthy, thee ae two sites which ae chaacteized by bald spots whee vegetation has been cleaed. These ae shown as degaded on Figue 3. The Patteson pacel was disked by the Alameda County Mosquito Abatement Distict. ACFCD does not know how the othe aea was damaged, but speculates that it was abandoned afte being used as a copland (Campbell, 1986, pes. comm.). t is also possible that the condition of this site is a esult of unauthoized filling o gading which may have been due to coodination poblems within ACFCD (Kelly, 1986, pes. comm.). At the pesent time, ACFCD has plans to dump dedge spoils on the same aea whee the salt mash havest mouse has been found (Figue 2). The dedge spoils ae the mud and silt that ae taken fom
- 135 - Figue 3. Souces: Plant Communities and Degaded Aeas. Field Wok, 1985-1986; Mille, 1986; Base Map fom Newak, Califonia Quadangle, 7.5 Minute Seies (USGS). New Alameda Ceek to keep the channel at a paticula depth (Campbell, 1986, pes. comm.). Dumping the spoils involves buying the plants and animals undeneath and also exposing them to heavy metals (Jenkins, 1984). The Endangeed Species Act potects the aea whee dumping is planned and pevents any othe action that theatens it, so ACFCD cannot dump at this site. ACFCD should dump dedge spoils on aeas that ae aleady degaded instead of on aeas with bette habitat values. Anothe law that will affect ACFCD's futue land management options is the Food Secuity Act of 1985 (PL#99-198). t affects ACFCD since the agency leases what was once seasonal wetland to cabbage gowes (Figue 3). The Sod and Swamp Buste povision within the bill states that if the owne of a wetland leases a pat of his land fo agicultue he must develop a plan by 1990 to peseve a diffeent pat of his wetland in ode to continue leasing fo this pupose (Pencovic, 1986, pes. comm.). n othe wods, ACFCD will have to set aside a pecentage of its seasonal wetland as a peseve if it wants to continue leasing. To summaize, the biological and legal easons why ACFCD should be encouaged to convet its land into a pak o a peseve that also opeates as a flood basin aea ae twofold: (1) the Endangeed Species Act in fact pevents ACFCD fom utilizing the poposed dedge spoil sites fo that pupose, and (2) the Food Secuity Act of 1985 will place an ultimatum on ACFCD's lease to the cabbage fames.
- 136 - Recommendations The public needs to infom ACFCD and the U.S. Amy Cops of Enginees that it feels the Union City land would make a valuable peseve aea and that the Endangeed Species Act and the Food Secuity Act apply to it. Concened citizens need to point out to the two agencies and to local legislatos that the land could be a ich souce of education and eceation which would offe activities such as bid watching, guided natue walks, photogaphy, hiking, and hoseback iding while still opeating as a flood basin aea in the winte. What happens to ACFCD's land and the plants, bids and mammals that live thee may ultimately depend on such public input. REFERENCES CTED Campbell, Roge, Maintenance Enginee, Alameda County Flood Contol Wate Distict. cation, 5/16/86. Cogswell, D. Howad, Onithologist, Audubon Society. Pesonal communication, 1/15/86. Pesonal communi Havey, H.T., H.L. Mason, R. Gill, T.W. Wooste, 1977. The mashes of San Fancisco Bay: Thei attibutes and values; Unpublished epot fo San Fancisco Bay Consevation and Development Commission, 156pp. Jenkins, S.A., J.A. Baylod, D.L. nman, 1984. Opeating and maintaining tidal lagoons and estuaies; Unpublished epot fo the Geogaphy Banch of the Office of Naval Reseach, Contact *N0014-76- C-0631, 20pp. Kelly, Paul, Wildlife Biologist, Califonia Depatment of Fish and Game. 10/85-4/86. Pesonal communications, Mille, Kaen, Wildlife Biologist, U.S. Fish and Wildlife Sevice. Pesonal communications, 10/85-1/86. Onduff, R., 1974. 152pp. ntoduction to Califonia plant life; Bekeley, Univesity of Califonia Pess, Pencovic, Tei, Wildlife Biologist, U.S. Fish and Wildlife Sevice. 2/3/86 and 2/17/86. Pesonal communications, Pessle, J.D., 1973. Landscape modification though time: The Coyote Hills, Alameda County, Califonia; Unpublished maste's thesis fo the Califonia State Univesity - Haywad, Geology Depatment, 102pp.