Biogeography of Lake Merced Appendices

Climatology

Table For Figure 1.

Period of Record General Climate Summary - Temperature 1948-1999
Station: (047767) SAN FRANCISCO Richmond/Oceanside
	Max	Min	Mean	High	Low
Jan	57.4	43.8	50.7	79	29
Feb	59.7	45.9	52.7	77	29
Mar	60.2	46.5	53.4	79	33
Apr	60.9	47.3	54.1	87	35
May	61.2	49.4	55.3	89	40
Jun	62.7	51.4	57.1	88	36
Jul	63.5	53.4	58.4	86	45
Aug	64.4	54.5	59.5	95	47
Sep	66.2	54.3	60.3	96	43
Oct	66.3	52.1	59.2	99	40
Nov	62.3	48.1	55.2	85	33
Dec	57.5	44.3	50.9	73	26

Annual	61.9	49.3	55.6	99	26
Winter	58.2	44.7	51.4	79	26
Spring	60.8	47.8	54.3	89	33
Summer	63.5	53.1	58.3	95	36
Fall	64.9	51.5	58.2	99	33

Table for Figure 2

Station: (047767) SAN FRANCISCO- Richmond/Oceanside
1948 -1999
Precipitation in Inches
	Mean	High	Low	1 day Max
Jan	4.34	10.17	0.4	2.65
Feb	3.34	13.9	0	3.9
Mar	2.89	9.74	0	2.52
Apr	1.18	5.24	0	1.45
May	0.46	3.68	0	1.44
Jun	0.15	1.89	0	1.66
Jul	0.02	0.55	0	0.5
Aug	0.1	1.2	0	1.2
Sep	0.19	2.05	0	1.98
Oct	1.08	7.94	0	3.15
Nov	2.81	7.3	0	2.12
Dec	3.24	6.88	0	3.43

Annual	19.8	35.8	10.73	3.9
Winter	10.92	25.44	2.87	3.9
Spring	4.53	13.13	0	2.52
Summer	0.28	1.89	0	1.66
Fall	4.08	11.64	0.07	3.15

Hydrology

APPENDIX 1. Potential Contaminant Sources in the Lake Merced Watershed (Camp
Dresser & McKee 1999).

CONTAMINANT SOURCE	SUPPORTING INFORMATION AND OBSERVATIONS	RECOMMENDATIONS
Groundwater Transport of Contaminants	One LUST is located within one-quarter mile of Lake Merced. Nitrate present in the exfiltration from the combined sewer system can enter the groundwater and be discharged to the Lake.	Include testing from petroleum products in groundwater and lake water quality monitoring. Implement 1997 groundwater quality monitoring program, including testing for nitrates.
Stormwater Overflow from Vista Grande Channel	Stormwater overflow has occurred when the channel outfall capacity was exceeded. Water quality stormwater overflow is not known.	Review 1998/99 SPEAC water quality monitoring data from channel to determine possible impacts to Lake and develop future channel monitoring program. Provide regular maintenance on channel to prevent back-up due to clogged debris. Review Daly City monitoring program for adequacy in preventing overflows.
Combined sewer Overflow	Three direct sewer overflows locations are shown on maps of sewer collection system surrounding Lake. The overflow structures were no accessed during site visit. City staff believe overflows have been removed; however, no records are available regarding removals. Overflow at manholes on combined sewer may occur during peak flows in wet weather events. This overflow would drain into the lake via storm drain inlets around the Lake.	Perform a field inspection to access the overflow locations to verify they have been removed. Remove from service if still connected. Perform a study to determine the return period for overflows of sewers in the Lake Merced area.
Stormwater from Surrounding Watershed	Water quality of stormwater from Lake Merced watershed is not fully known. Review of City sewer maps does not show storm drain inlets The SFPD Range is currently required by DTSC to perform a PEA to assess environmental, ecological and health risk of lead on the site.	Review 1998/99 SPEAC water quality monitoring data to determine possible impact to the Lake. Perform a comprehensive investigation of storm drain inlets around the Lake to determine connection to the combined sewer or lake discharge. Review PEA to determine if runoff from the shooting range has potential to impact Lake water quality.

CONTAMINANT SOURCE	SUPPORTING INFORMATION AND OBSERVATIONS	RECOMMENDATIONS
Pesticide/Herbicide Contamination	Pesticides and herbicides are used and stored on golf courses in the watershed. Potential for contamination of groundwater and surface water if chemicals are not applied or stored properly.	Include testing of pesticides and herbicides in groundwater and lake water quality monitoring, especially near sites of potential runoff from the golf course. Include pesticide and herbicide use BMPs in lease agreements. Continue implementation of integrated Pest Management Plan and current practice of proper storage.
Unplanned Treated water Discharge	Blowoffs from treated water pipeline must be dechlorinated before discharge	Verify readiness of dechlorination facilities.
Recreation	Lake receives heavy non-contact use. The major contaminants associated with this recreational use include: Litter and other discarded debris left by lake users. Trash receptacles are placed at designated locations around the Lake, are not always utilized. Sediments can be washed off trails if erosion management controls are not in effect. Some trails with erosion are not authorized. Human waste products (urine and feces) from lake users. Shooting at the Pacific Rod and Gun Club has deposited lead in the Lake. An enforcement order is still pending against the Club from the Regional water Quality Control Board. Studies have shown little impact to lake water quality from lead shot.	Perform usage study of the Lake to identify/quantify effects of recreational use on the water quality. Evaluate adequacy of existing waste disposal program. Post signs and/or close trails where erosion or wildlife disturbance is problematic. Evaluate adequacy of restroom facility in usage study. Continue review of lead monitoring and cleanup efforts performed by the Club.
Solid Waste	Dumpsters are used where appropriate, although some dumpsters areas have become "storage" for obsolete objects. Contaminants from uncovered waste can be carried into the Lake by runoff.	Suitable storage areas and cover of wastes should be provided where feasible. Incorporate water quality protection through land use management into new leases.

CONTAMINANT SOURCE	SUPPORTING INFORMATION AND OBSERVATIONS	RECOMMENDATIONS
Traffic Accidents/Spills	No restrictions on hazardous materials transport on roads surrounding lake. Spills can flow directly to the Lake through storm drain inlets.	Investigate areas where guardrails or decreased speed requirements may be beneficial.
Unauthorized Activity	Illegal dumping occurs at parking lots and other areas along the shoreline.	Keep records of illegal dumped materials to determine cost-effectiveness of additional surveillance. Increase security provisions.
Seawater Intrusion	Past studies have assumed groundwater outflow west from the Lake to the ocean. This westward flow of water would prevent seawater intrusion to the Lake; however, no data on seawater intrusion exists.	Implement 1997 groundwater monitoring program which includes provision for seawater intrusion monitoring.

ANNEX FLORA

The following systematic list of species found on the San Francisco sand-dunes was provided by Wagstaff (1962) who carried out a study of the flora of the San Francisco sand-dunes composition and adaptations between 1938-1962. Some of these species may have been part of the flora found at Lake Merced during the pre-Hispanic and early Spanish periods. Wagstaff (1962) noted that "listing is according to the arrangement given in the Manual of the Flowering Plants of California by Dr. W.L. Jepson."

Polypodiaceae: Pteris aquilina L.
Pinaceae: Pinus radiata Don.
Poaceae: Bromus sterilis L.; Bromus rigidus Roth; Bromus hordaceus L.; Bromus maritimus; Poa douglasii                      Ness; Agropyron junceum; Hordum murinum L., Lollium perenne L., Ammophila arenaria L.,                      Echinochloa crusgalli L.; Avena fatua L.
Cyperaceae: Eleocahris acicularis R. & S.
Juncaceae: Juncus lescurii Boland.; Juncus falcatus E., Mey., Rush.; Juncus phaeocephalus Engelm., Rush
Salicaceae: Salix lasiolepis Benth.
Myricaceae: Myrica californica Cham.
Polygonaceae: Polygonum paronychia C. & S.; Rumex occidentalis Wats.; Rumex acetosella L.;                              Chorizanthe pungens Benth.; Eriogonum latifolium Sm.
Chenopodiaceae: Chenopodium album L.; Roubieva multifida L.
Nyctaginaceae: Abronia latifolia Esch.; Abronia unbellata Lam.
Mesembriamtheaceae: Mesembriamthemum aequilaterale How.
Portulacaceae: Calandrinia caulescens H.B.K.
Caryophyllaceae: Stellaria media L.; Spergularia clevelandii Greene; Pentacaena ramosissima H. & A.;                                  Silene gallica L.
Ranunculaceae: Ranunculus californicus Benth.
Papaveraceae: Eschscholuzia californica Schlecht.
Brassicaceae: Cakile edentula Hook.; Cakile maritima Scop.; Raphanus sativus L.; Brassica adpressa                              Boiss.; Brassica campestris L.; Brassica nigra L.; Erysimum capitatum Dougl.; Alyssum                              maritimum L.
Rosaceae: Rubus vitifolius C. & S.; Fragaria californica C. & S.; Fragaria chilensis L.;
Fabaceae: Lupinus bicolor Lindl.; Lupinus arboreus Sims.; Lupinus chamissonis Esch.; Lupinus albifrons                         Benth; Medicago hispida Gaertn.; Melilotus indica All.; Lotus strigosus Nutt.; Lotus eriophorus                         Greene; Lotus scoparius Nutt.; Lathyrus littoralis Nutt.
Geraniaceae: Erodium botrys Bertol.; Erodium moschatum L'Her.; Erodium cicutarium L'Her.
Euphorbiaceae: Euphorbia crenulata Engelm.; Rhus diversiloba T. & G.
Rhamnaceae: Rhamnus californica Esch.
Malvaceae: Malva sylvestris L.; Malva parviflora L.
Cucurbitaceae: Echinocystis fabaceae Naud.
Oenotheraceae: Epilobium minutum Lindl.; Epilobium paniculatum Nutt.; Oenothera spiralis Hook.
Umbelliferaceae: Sanicula arctopoides H. & A.
Primulacaceae: Anagallis arvensis L.
Convolvulaceae: Convolvulus soldanella L.
Polemoniaceae: Linanthus parviflorus Benth.
Hydrophyllaceae: Nemophila mensiesii H. & A.; Phacelia douglasii Benth.
Boraginaceae: Amsinckia intermedia F. & M.; Cryptantha leiocarpa F. & M.
Lamiaceae: Micromeria chamissonis Benth.
Solanaceae: Solanum nigrum L.
Scrophulariaceae: Scrophularia californica Cham.; Diplacus aurantiacus Jepson.; Mimulus guttatus DC.;                                     Castilleia latifolia H. & A.
Plantaginaceae: Plantago lanceolata L.; Plantago maritima L.
Caprifoliaceae: Lonicera involucrata Banks.
Asteraceae: Hypochoeris glabra L.; Hypochoeris radicata L.; Lactuca serriola L.; Sonchus oleraceus L.;                          Agoseris apargioides Greene.; Ericameria ericoides Less.; Lessingia germanorum Cham.;                          Erigeron canadensis L.; Erigeron glaucus Ker.; Baccharis piluralis D.C.; Anaphalis                          margaritacea L.; Franseria bipinnatifida Nutt.; Franseria chamissonis Less.; Eriophyllum                          staechdifolium Jepson.; Anthemis cotula L.; Achillea millefolium L.; Tanacetum camphoratum                          Less.; Artemisia pycnocephala DC.; Cotula australis Hook.; Cotula coronopifolia L.; Senecio                          elegans L.; Senecio vulgaris L.; Cirsium occidentale Nutt.