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precipitation is a:le to late spr ing snows influenced by south- easterly winds on upslopes and from summer thunderstorms. Pikes Peak produces a "rain shadow" which causes a semiarid zone to the east. Annual precipitation varies from a low of 8 inches to a high of 20 inches in the higher elevations. Normal annual precipi- tation for Colorado Springs is 13.2 inches, with the normal maximum monthly amount of 2.4 inches occurring in July (Reference 5). 2.3 Principal Flood Problems Most of the flood-producing storms in the study area occur from May through August. The most severe storms occur in late spring or early fall when polar air intrusions are more intense. Isolated summer thunderstorms are frequently severe, but limited in areal extent. Available records do not indicate that snowmelt has con- tributed significantly to flood occurrences in the study area. Floods are characterized by high peak flows, moderate volumes, and short durations. Available flood history for El Paso County is almost exclusively concerned with the larger aspects of flooding on Fountain or Monu- ment Creeks in the urbanized areas. Major flooding probably included simultaneous flooding on the smaller streams as well. References to the smaller streams appeared only rarely in newspaper accounts until rece~tly. Specific information on the intensity, duration, and magnitude of the storms and flood effects is generally lacking. The ~~y 1935 flood is t~e largest recorded flood: 55,000 cubic feet per second (cfs) on t~e Fountain Creek above the confluence with Ji~~y Camp C~eek (Reference 6). This storm, which was concen- trated chiefly over the Kettle Creek basin, also caused the largest known floo~ O~ Monument Creek, 50,000 cfs (Reference 7). In Colo- rado Springs, Mo~ument Creek attained its peak flow within 2.5 ho~rs and was back within the banks 3 hours later. The flow rate o~ t~is flood exceeded the estimated 5uO-year peak flow rate of the 3.rea. B~low the conflJence of Jimmy Canp Creek with Fou~tain Creek, the J~ne 1965 flood probably exceeded all known floods i~ E1 Paso County. This flood was caused primarily ~y Ji~my Camp Creek. At a point 4.5 ~ile5 above the cO'1fluence with Fountain Creek, the estimated p~ak discharge was 124,000 cfs (Reference 6), which ~s estimated to be a rec~rrence interval far exceeding 500 years. Developments su~ject to flood damage consist of residential proper- ties 3.~C co~mercial aDd light industrial establishments. Some ~r~d~es and culverts across the streams are constrictive to flo0d- flows a~d contribute to flooding problems. Generally, the bridges 3~r0SS ?ountai~ a~G ~o~ume~t Creeks will pass at least the lOO-year f:cci, with the ~st co~st[ictive bridges and culverts being on ':.~<:! s:>:aller 5trea:!lS. Other obstructions to flood flows i:1clude 9