Agenda packet — Yorba Linda City Council, February 3, 2026 (part 8 of 11)

154 4.6348 0.0153
155 4.6501 0.0153
156 4.6653 0.0152
157 4.6805 0.0152
158 4.6956 0.0151
159 4.7107 0.0151
160 4.7257 0.0150
161 4.7407 0.0150
162 4.7556 0.0149
163 4.7705 0.0149
164 4.7853 0.0148
165 4.8001 0.0148
166 4.8149 0.0148
167 4.8296 0.0147
168 4.8443 0.0147
169 4.8589 0.0146
170 4.8735 0.0146
171 4.8880 0.0145
172 4.9025 0.0145
173 4.9170 0.0145
174 4.9314 0.0144
175 4.9458 0.0144
176 4.9601 0.0143
177 4.9744 0.0143
178 4.9887 0.0143
179 5.0029 0.0142
180 5.0171 0.0142
181 5.0312 0.0141
182 5.0453 0.0141
183 5.0594 0.0141
184 5.0734 0.0140
185 5.0874 0.0140
186 5.1013 0.0140
187 5.1153 0.0139
188 5.1291 0.0139
189 5.1430 0.0138
190 5.1568 0.0138
191 5.1705 0.0138
192 5.1843 0.0137
193 5.1980 0.0137
194 5.2116 0.0137
195 5.2253 0.0136
196 5.2389 0.0136
197 5.2524 0.0136
198 5.2659 0.0135
199 5.2794 0.0135
200 5.2929 0.0135
201 5.3063 0.0134
202 5.3197 0.0134
203 5.3331 0.0134

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204 5.3464 0.0133
205 5.3597 0.0133
206 5.3730 0.0133
207 5.3862 0.0132
208 5.3994 0.0132
209 5.4126 0.0132
210 5.4257 0.0131
211 5.4388 0.0131
212 5.4519 0.0131
213 5.4650 0.0130
214 5.4780 0.0130
215 5.4910 0.0130
216 5.5039 0.0130
217 5.5169 0.0129
218 5.5298 0.0129
219 5.5426 0.0129
220 5.5555 0.0128
221 5.5683 0.0128
222 5.5811 0.0128
223 5.5938 0.0128
224 5.6065 0.0127
225 5.6192 0.0127
226 5.6319 0.0127
227 5.6446 0.0126
228 5.6572 0.0126
229 5.6698 0.0126
230 5.6823 0.0126
231 5.6949 0.0125
232 5.7074 0.0125
233 5.7199 0.0125
234 5.7323 0.0125
235 5.7448 0.0124
236 5.7572 0.0124
237 5.7695 0.0124
238 5.7819 0.0124
239 5.7942 0.0123
240 5.8065 0.0123
241 5.8188 0.0123
242 5.8310 0.0123
243 5.8433 0.0122
244 5.8555 0.0122
245 5.8677 0.0122
246 5.8798 0.0122
247 5.8919 0.0121
248 5.9040 0.0121
249 5.9161 0.0121
250 5.9282 0.0121
251 5.9402 0.0120
252 5.9522 0.0120
253 5.9642 0.0120

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254 5.9762 0.0120
255 5.9881 0.0119
256 6.0000 0.0119
257 6.0119 0.0119
258 6.0238 0.0119
259 6.0357 0.0118
260 6.0475 0.0118
261 6.0593 0.0118
262 6.0711 0.0118
263 6.0828 0.0118
264 6.0946 0.0117
265 6.1063 0.0117
266 6.1180 0.0117
267 6.1296 0.0117
268 6.1413 0.0117
269 6.1529 0.0116
270 6.1645 0.0116
271 6.1761 0.0116
272 6.1877 0.0116
273 6.1992 0.0115
274 6.2108 0.0115
275 6.2223 0.0115
276 6.2337 0.0115
277 6.2452 0.0115
278 6.2566 0.0114
279 6.2681 0.0114
280 6.2795 0.0114
281 6.2909 0.0114
282 6.3022 0.0114
283 6.3136 0.0113
284 6.3249 0.0113
285 6.3362 0.0113
286 6.3475 0.0113
287 6.3587 0.0113
288 6.3700 0.0112
--------------------------------------------------------------------- Unit Unit Unit Effective
Period Rainfall Soil-Loss Rainfall
(number) (In) (In) (In)
--------------------------------------------------------------------- 1 0.0112 0.0008 0.0105
2 0.0113 0.0008 0.0105
3 0.0113 0.0008 0.0105
4 0.0113 0.0008 0.0105
5 0.0114 0.0008 0.0106
6 0.0114 0.0008 0.0106
7 0.0114 0.0008 0.0106
8 0.0114 0.0008 0.0107
9 0.0115 0.0008 0.0107
10 0.0115 0.0008 0.0107

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11 0.0115 0.0008 0.0107
12 0.0116 0.0008 0.0108
13 0.0116 0.0008 0.0108
14 0.0116 0.0008 0.0108
15 0.0117 0.0008 0.0109
16 0.0117 0.0008 0.0109
17 0.0117 0.0008 0.0109
18 0.0118 0.0008 0.0109
19 0.0118 0.0008 0.0110
20 0.0118 0.0008 0.0110
21 0.0119 0.0008 0.0111
22 0.0119 0.0008 0.0111
23 0.0119 0.0008 0.0111
24 0.0120 0.0008 0.0111
25 0.0120 0.0008 0.0112
26 0.0120 0.0008 0.0112
27 0.0121 0.0008 0.0112
28 0.0121 0.0008 0.0113
29 0.0122 0.0008 0.0113
30 0.0122 0.0008 0.0113
31 0.0122 0.0008 0.0114
32 0.0123 0.0008 0.0114
33 0.0123 0.0009 0.0115
34 0.0123 0.0009 0.0115
35 0.0124 0.0009 0.0115
36 0.0124 0.0009 0.0115
37 0.0125 0.0009 0.0116
38 0.0125 0.0009 0.0116
39 0.0125 0.0009 0.0117
40 0.0126 0.0009 0.0117
41 0.0126 0.0009 0.0117
42 0.0126 0.0009 0.0118
43 0.0127 0.0009 0.0118
44 0.0127 0.0009 0.0118
45 0.0128 0.0009 0.0119
46 0.0128 0.0009 0.0119
47 0.0129 0.0009 0.0120
48 0.0129 0.0009 0.0120
49 0.0130 0.0009 0.0121
50 0.0130 0.0009 0.0121
51 0.0130 0.0009 0.0121
52 0.0131 0.0009 0.0122
53 0.0131 0.0009 0.0122
54 0.0132 0.0009 0.0123
55 0.0132 0.0009 0.0123
56 0.0133 0.0009 0.0123
57 0.0133 0.0009 0.0124
58 0.0134 0.0009 0.0124
59 0.0134 0.0009 0.0125
60 0.0135 0.0009 0.0125

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61 0.0135 0.0009 0.0126
62 0.0136 0.0009 0.0126
63 0.0136 0.0009 0.0127
64 0.0137 0.0009 0.0127
65 0.0137 0.0010 0.0128
66 0.0138 0.0010 0.0128
67 0.0138 0.0010 0.0129
68 0.0139 0.0010 0.0129
69 0.0140 0.0010 0.0130
70 0.0140 0.0010 0.0130
71 0.0141 0.0010 0.0131
72 0.0141 0.0010 0.0131
73 0.0142 0.0010 0.0132
74 0.0142 0.0010 0.0132
75 0.0143 0.0010 0.0133
76 0.0143 0.0010 0.0133
77 0.0144 0.0010 0.0134
78 0.0145 0.0010 0.0135
79 0.0145 0.0010 0.0135
80 0.0146 0.0010 0.0136
81 0.0147 0.0010 0.0137
82 0.0147 0.0010 0.0137
83 0.0148 0.0010 0.0138
84 0.0148 0.0010 0.0138
85 0.0149 0.0010 0.0139
86 0.0150 0.0010 0.0139
87 0.0151 0.0010 0.0140
88 0.0151 0.0010 0.0141
89 0.0152 0.0011 0.0142
90 0.0153 0.0011 0.0142
91 0.0154 0.0011 0.0143
92 0.0154 0.0011 0.0143
93 0.0155 0.0011 0.0144
94 0.0156 0.0011 0.0145
95 0.0157 0.0011 0.0146
96 0.0157 0.0011 0.0146
97 0.0158 0.0011 0.0147
98 0.0159 0.0011 0.0148
99 0.0160 0.0011 0.0149
100 0.0161 0.0011 0.0149
101 0.0162 0.0011 0.0150
102 0.0162 0.0011 0.0151
103 0.0163 0.0011 0.0152
104 0.0164 0.0011 0.0153
105 0.0165 0.0011 0.0154
106 0.0166 0.0011 0.0154
107 0.0167 0.0012 0.0156
108 0.0168 0.0012 0.0156
109 0.0169 0.0012 0.0157
110 0.0170 0.0012 0.0158

Page 1389 of 2028 ends

111 0.0171 0.0012 0.0159
112 0.0172 0.0012 0.0160
113 0.0173 0.0012 0.0161
114 0.0174 0.0012 0.0162
115 0.0175 0.0012 0.0163
116 0.0176 0.0012 0.0164
117 0.0178 0.0012 0.0165
118 0.0178 0.0012 0.0166
119 0.0180 0.0012 0.0168
120 0.0181 0.0013 0.0168
121 0.0182 0.0013 0.0170
122 0.0183 0.0013 0.0171
123 0.0185 0.0013 0.0172
124 0.0186 0.0013 0.0173
125 0.0188 0.0013 0.0175
126 0.0189 0.0013 0.0176
127 0.0190 0.0013 0.0177
128 0.0191 0.0013 0.0178
129 0.0193 0.0013 0.0180
130 0.0194 0.0013 0.0181
131 0.0196 0.0014 0.0183
132 0.0198 0.0014 0.0184
133 0.0200 0.0014 0.0186
134 0.0201 0.0014 0.0187
135 0.0203 0.0014 0.0189
136 0.0204 0.0014 0.0190
137 0.0207 0.0014 0.0192
138 0.0208 0.0014 0.0193
139 0.0210 0.0015 0.0196
140 0.0212 0.0015 0.0197
141 0.0214 0.0015 0.0200
142 0.0216 0.0015 0.0201
143 0.0219 0.0015 0.0203
144 0.0220 0.0015 0.0205
145 0.0222 0.0015 0.0206
146 0.0223 0.0015 0.0208
147 0.0226 0.0016 0.0211
148 0.0228 0.0016 0.0212
149 0.0231 0.0016 0.0215
150 0.0233 0.0016 0.0217
151 0.0237 0.0016 0.0220
152 0.0239 0.0017 0.0222
153 0.0243 0.0017 0.0226
154 0.0245 0.0017 0.0228
155 0.0249 0.0017 0.0232
156 0.0251 0.0017 0.0234
157 0.0256 0.0018 0.0238
158 0.0258 0.0018 0.0240
159 0.0263 0.0018 0.0245
160 0.0266 0.0018 0.0247

Page 1390 of 2028 ends

161 0.0271 0.0019 0.0253
162 0.0274 0.0019 0.0255
163 0.0280 0.0019 0.0261
164 0.0283 0.0020 0.0264
165 0.0290 0.0020 0.0270
166 0.0294 0.0020 0.0273
167 0.0301 0.0021 0.0280
168 0.0305 0.0021 0.0284
169 0.0294 0.0020 0.0274
170 0.0298 0.0021 0.0278
171 0.0308 0.0021 0.0287
172 0.0313 0.0022 0.0291
173 0.0324 0.0022 0.0302
174 0.0330 0.0023 0.0307
175 0.0343 0.0024 0.0319
176 0.0350 0.0024 0.0326
177 0.0365 0.0025 0.0340
178 0.0374 0.0026 0.0348
179 0.0393 0.0027 0.0366
180 0.0403 0.0028 0.0375
181 0.0427 0.0030 0.0397
182 0.0440 0.0030 0.0410
183 0.0471 0.0033 0.0439
184 0.0489 0.0034 0.0456
185 0.0561 0.0039 0.0522
186 0.0587 0.0041 0.0546
187 0.0653 0.0045 0.0608
188 0.0695 0.0048 0.0647
189 0.0787 0.0054 0.0733
190 0.0874 0.0060 0.0814
191 0.1189 0.0072 0.1116
192 0.1563 0.0072 0.1491
193 0.3930 0.0072 0.3857
194 0.0996 0.0069 0.0927
195 0.0747 0.0052 0.0695
196 0.0617 0.0043 0.0575
197 0.0510 0.0035 0.0474
198 0.0455 0.0031 0.0424
199 0.0414 0.0029 0.0386
200 0.0383 0.0026 0.0356
201 0.0357 0.0025 0.0333
202 0.0336 0.0023 0.0313
203 0.0319 0.0022 0.0296
204 0.0303 0.0021 0.0282
205 0.0309 0.0021 0.0288
206 0.0297 0.0021 0.0277
207 0.0287 0.0020 0.0267
208 0.0277 0.0019 0.0258
209 0.0269 0.0019 0.0250
210 0.0261 0.0018 0.0243

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211 0.0254 0.0018 0.0236
212 0.0247 0.0017 0.0230
213 0.0241 0.0017 0.0224
214 0.0235 0.0016 0.0219
215 0.0230 0.0016 0.0214
216 0.0225 0.0016 0.0209
217 0.0221 0.0015 0.0206
218 0.0217 0.0015 0.0202
219 0.0213 0.0015 0.0198
220 0.0209 0.0014 0.0195
221 0.0205 0.0014 0.0191
222 0.0202 0.0014 0.0188
223 0.0199 0.0014 0.0185
224 0.0195 0.0014 0.0182
225 0.0192 0.0013 0.0179
226 0.0190 0.0013 0.0176
227 0.0187 0.0013 0.0174
228 0.0184 0.0013 0.0171
229 0.0182 0.0013 0.0169
230 0.0179 0.0012 0.0167
231 0.0177 0.0012 0.0165
232 0.0175 0.0012 0.0163
233 0.0172 0.0012 0.0161
234 0.0170 0.0012 0.0159
235 0.0168 0.0012 0.0157
236 0.0166 0.0012 0.0155
237 0.0165 0.0011 0.0153
238 0.0163 0.0011 0.0152
239 0.0161 0.0011 0.0150
240 0.0159 0.0011 0.0148
241 0.0158 0.0011 0.0147
242 0.0156 0.0011 0.0145
243 0.0155 0.0011 0.0144
244 0.0153 0.0011 0.0143
245 0.0152 0.0010 0.0141
246 0.0150 0.0010 0.0140
247 0.0149 0.0010 0.0139
248 0.0148 0.0010 0.0137
249 0.0146 0.0010 0.0136
250 0.0145 0.0010 0.0135
251 0.0144 0.0010 0.0134
252 0.0143 0.0010 0.0133
253 0.0141 0.0010 0.0132
254 0.0140 0.0010 0.0131
255 0.0139 0.0010 0.0130
256 0.0138 0.0010 0.0128
257 0.0137 0.0009 0.0128
258 0.0136 0.0009 0.0127
259 0.0135 0.0009 0.0126
260 0.0134 0.0009 0.0125

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261 0.0133 0.0009 0.0124
262 0.0132 0.0009 0.0123
263 0.0131 0.0009 0.0122
264 0.0130 0.0009 0.0121
265 0.0129 0.0009 0.0120
266 0.0128 0.0009 0.0120
267 0.0128 0.0009 0.0119
268 0.0127 0.0009 0.0118
269 0.0126 0.0009 0.0117
270 0.0125 0.0009 0.0116
271 0.0124 0.0009 0.0116
272 0.0124 0.0009 0.0115
273 0.0123 0.0008 0.0114
274 0.0122 0.0008 0.0114
275 0.0121 0.0008 0.0113
276 0.0121 0.0008 0.0112
277 0.0120 0.0008 0.0112
278 0.0119 0.0008 0.0111
279 0.0118 0.0008 0.0110
280 0.0118 0.0008 0.0110
281 0.0117 0.0008 0.0109
282 0.0117 0.0008 0.0108
283 0.0116 0.0008 0.0108
284 0.0115 0.0008 0.0107
285 0.0115 0.0008 0.0107
286 0.0114 0.0008 0.0106
287 0.0113 0.0008 0.0106
288 0.0113 0.0008 0.0105
-------------------------------------------------------------------- -------------------------------------------------------------------- Total soil rain loss = 0.42(In)
Total effective rainfall = 5.95(In)
Peak flow rate in flood hydrograph = 6.99(CFS)
--------------------------------------------------------------------- ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 24 - H O U R S T O R M
R u n o f f H y d r o g r a p h
-------------------------------------------------------------------- Hydrograph in 5 Minute intervals ((CFS))
-------------------------------------------------------------------- Time(h+m) Volume Ac.Ft Q(CFS) 0 2.5 5.0 7.5 10.0
----------------------------------------------------------------------- 0+ 5 0.0001 0.02 Q | | | |
0+10 0.0008 0.10 Q | | | |
0+15 0.0024 0.23 Q | | | |
0+20 0.0045 0.30 VQ | | | |
0+25 0.0067 0.33 VQ | | | |
0+30 0.0090 0.33 VQ | | | |
0+35 0.0113 0.34 VQ | | | |

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0+40 0.0137 0.34 VQ | | | |
0+45 0.0160 0.34 VQ | | | |
0+50 0.0183 0.34 VQ | | | |
0+55 0.0207 0.34 VQ | | | |
1+ 0 0.0230 0.34 VQ | | | |
1+ 5 0.0254 0.34 VQ | | | |
1+10 0.0278 0.34 VQ | | | |
1+15 0.0301 0.34 VQ | | | |
1+20 0.0325 0.35 VQ | | | |
1+25 0.0349 0.35 |Q | | | |
1+30 0.0373 0.35 |Q | | | |
1+35 0.0397 0.35 |Q | | | |
1+40 0.0421 0.35 |Q | | | |
1+45 0.0445 0.35 |Q | | | |
1+50 0.0469 0.35 |Q | | | |
1+55 0.0494 0.35 |Q | | | |
2+ 0 0.0518 0.35 |Q | | | |
2+ 5 0.0543 0.35 |Q | | | |
2+10 0.0567 0.36 |Q | | | |
2+15 0.0592 0.36 |Q | | | |
2+20 0.0616 0.36 |Q | | | |
2+25 0.0641 0.36 |Q | | | |
2+30 0.0666 0.36 |QV | | | |
2+35 0.0691 0.36 |QV | | | |
2+40 0.0715 0.36 |QV | | | |
2+45 0.0741 0.36 |QV | | | |
2+50 0.0766 0.36 |QV | | | |
2+55 0.0791 0.37 |QV | | | |
3+ 0 0.0816 0.37 |QV | | | |
3+ 5 0.0841 0.37 |QV | | | |
3+10 0.0867 0.37 |QV | | | |
3+15 0.0892 0.37 |QV | | | |
3+20 0.0918 0.37 |QV | | | |
3+25 0.0943 0.37 |QV | | | |
3+30 0.0969 0.37 |QV | | | |
3+35 0.0995 0.37 |Q V | | | |
3+40 0.1021 0.38 |Q V | | | |
3+45 0.1047 0.38 |Q V | | | |
3+50 0.1073 0.38 |Q V | | | |
3+55 0.1099 0.38 |Q V | | | |
4+ 0 0.1125 0.38 |Q V | | | |
4+ 5 0.1151 0.38 |Q V | | | |
4+10 0.1178 0.38 |Q V | | | |
4+15 0.1204 0.38 |Q V | | | |
4+20 0.1231 0.39 |Q V | | | |
4+25 0.1258 0.39 |Q V | | | |
4+30 0.1284 0.39 |Q V | | | |
4+35 0.1311 0.39 |Q V | | | |
4+40 0.1338 0.39 |Q V | | | |
4+45 0.1365 0.39 |Q V | | | |

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4+50 0.1393 0.39 |Q V | | | |
4+55 0.1420 0.40 |Q V | | | |
5+ 0 0.1447 0.40 |Q V | | | |
5+ 5 0.1475 0.40 |Q V | | | |
5+10 0.1502 0.40 |Q V | | | |
5+15 0.1530 0.40 |Q V | | | |
5+20 0.1558 0.40 |Q V | | | |
5+25 0.1585 0.40 |Q V | | | |
5+30 0.1613 0.41 |Q V | | | |
5+35 0.1641 0.41 |Q V | | | |
5+40 0.1670 0.41 |Q V | | | |
5+45 0.1698 0.41 |Q V | | | |
5+50 0.1726 0.41 |Q V | | | |
5+55 0.1755 0.41 |Q V | | | |
6+ 0 0.1784 0.42 |Q V | | | |
6+ 5 0.1812 0.42 |Q V | | | |
6+10 0.1841 0.42 |Q V | | | |
6+15 0.1870 0.42 |Q V | | | |
6+20 0.1899 0.42 |Q V | | | |
6+25 0.1928 0.42 |Q V | | | |
6+30 0.1958 0.43 |Q V | | | |
6+35 0.1987 0.43 |Q V | | | |
6+40 0.2017 0.43 |Q V | | | |
6+45 0.2047 0.43 |Q V | | | |
6+50 0.2076 0.43 |Q V | | | |
6+55 0.2106 0.44 |Q V | | | |
7+ 0 0.2137 0.44 |Q V | | | |
7+ 5 0.2167 0.44 |Q V | | | |
7+10 0.2197 0.44 |Q V | | | |
7+15 0.2228 0.44 |Q V | | | |
7+20 0.2258 0.45 |Q V | | | |
7+25 0.2289 0.45 |Q V | | | |
7+30 0.2320 0.45 |Q V | | | |
7+35 0.2351 0.45 |Q V | | | |
7+40 0.2383 0.45 |Q V | | | |
7+45 0.2414 0.46 |Q V | | | |
7+50 0.2446 0.46 |Q V | | | |
7+55 0.2477 0.46 |Q V | | | |
8+ 0 0.2509 0.46 |Q V | | | |
8+ 5 0.2541 0.47 |Q V | | | |
8+10 0.2573 0.47 |Q V | | | |
8+15 0.2606 0.47 |Q V | | | |
8+20 0.2638 0.47 |Q V | | | |
8+25 0.2671 0.47 |Q V | | | |
8+30 0.2704 0.48 |Q V | | | |
8+35 0.2737 0.48 |Q V | | | |
8+40 0.2770 0.48 |Q V | | | |
8+45 0.2803 0.48 |Q V | | | |
8+50 0.2837 0.49 |Q V | | | |
8+55 0.2871 0.49 |Q V | | | |

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9+ 0 0.2905 0.49 |Q V | | | |
9+ 5 0.2939 0.50 |Q V | | | |
9+10 0.2973 0.50 |Q V| | | |
9+15 0.3008 0.50 | Q V| | | |
9+20 0.3043 0.50 | Q V| | | |
9+25 0.3078 0.51 | Q V| | | |
9+30 0.3113 0.51 | Q V| | | |
9+35 0.3148 0.51 | Q V| | | |
9+40 0.3184 0.52 | Q V| | | |
9+45 0.3220 0.52 | Q V| | | |
9+50 0.3256 0.52 | Q V| | | |
9+55 0.3292 0.53 | Q V | | |
10+ 0 0.3328 0.53 | Q V | | |
10+ 5 0.3365 0.53 | Q V | | |
10+10 0.3402 0.54 | Q V | | |
10+15 0.3440 0.54 | Q V | | |
10+20 0.3477 0.55 | Q V | | |
10+25 0.3515 0.55 | Q V | | |
10+30 0.3553 0.55 | Q V | | |
10+35 0.3591 0.56 | Q V | | |
10+40 0.3630 0.56 | Q |V | | |
10+45 0.3669 0.57 | Q |V | | |
10+50 0.3708 0.57 | Q |V | | |
10+55 0.3748 0.57 | Q |V | | |
11+ 0 0.3787 0.58 | Q |V | | |
11+ 5 0.3827 0.58 | Q |V | | |
11+10 0.3868 0.59 | Q |V | | |
11+15 0.3909 0.59 | Q |V | | |
11+20 0.3950 0.60 | Q | V | | |
11+25 0.3991 0.60 | Q | V | | |
11+30 0.4033 0.61 | Q | V | | |
11+35 0.4075 0.61 | Q | V | | |
11+40 0.4118 0.62 | Q | V | | |
11+45 0.4161 0.62 | Q | V | | |
11+50 0.4204 0.63 | Q | V | | |
11+55 0.4248 0.64 | Q | V | | |
12+ 0 0.4292 0.64 | Q | V | | |
12+ 5 0.4337 0.65 | Q | V | | |
12+10 0.4382 0.65 | Q | V | | |
12+15 0.4427 0.66 | Q | V | | |
12+20 0.4473 0.66 | Q | V | | |
12+25 0.4519 0.67 | Q | V | | |
12+30 0.4566 0.68 | Q | V | | |
12+35 0.4613 0.69 | Q | V | | |
12+40 0.4661 0.69 | Q | V | | |
12+45 0.4709 0.70 | Q | V | | |
12+50 0.4758 0.71 | Q | V | | |
12+55 0.4808 0.72 | Q | V | | |
13+ 0 0.4858 0.73 | Q | V | | |
13+ 5 0.4909 0.74 | Q | V | | |

Page 1396 of 2028 ends

13+10 0.4960 0.75 | Q | V | | |
13+15 0.5012 0.76 | Q | V | | |
13+20 0.5065 0.77 | Q | V | | |
13+25 0.5119 0.78 | Q | V | | |
13+30 0.5173 0.79 | Q | V | | |
13+35 0.5229 0.80 | Q | V | | |
13+40 0.5285 0.82 | Q | V | | |
13+45 0.5342 0.83 | Q | V | | |
13+50 0.5400 0.84 | Q | V | | |
13+55 0.5459 0.86 | Q | V | | |
14+ 0 0.5519 0.87 | Q | V | | |
14+ 5 0.5581 0.89 | Q | V | | |
14+10 0.5642 0.89 | Q | V | | |
14+15 0.5703 0.89 | Q | V | | |
14+20 0.5765 0.89 | Q | V | | |
14+25 0.5828 0.91 | Q | V | | |
14+30 0.5892 0.93 | Q | V | | |
14+35 0.5958 0.96 | Q | V | | |
14+40 0.6026 0.98 | Q | V | | |
14+45 0.6095 1.01 | Q | V | | |
14+50 0.6167 1.04 | Q | V | | |
14+55 0.6242 1.08 | Q | V| | |
15+ 0 0.6318 1.12 | Q | V| | |
15+ 5 0.6398 1.16 | Q | V| | |
15+10 0.6481 1.20 | Q | V| | |
15+15 0.6568 1.26 | Q | V | |
15+20 0.6659 1.32 | Q | V | |
15+25 0.6754 1.39 | Q | V | |
15+30 0.6857 1.49 | Q | V | |
15+35 0.6969 1.62 | Q | |V | |
15+40 0.7090 1.76 | Q | |V | |
15+45 0.7222 1.92 | Q | | V | |
15+50 0.7367 2.10 | Q | | V | |
15+55 0.7529 2.36 | Q| | V | |
16+ 0 0.7724 2.83 | |Q | V | |
16+ 5 0.7995 3.94 | | Q | V | |
16+10 0.8417 6.12 | | | QV | |
16+15 0.8898 6.99 | | | Q | |
16+20 0.9230 4.81 | | Q| V | |
16+25 0.9437 3.01 | | Q | V | |
16+30 0.9582 2.10 | Q | | V| |
16+35 0.9701 1.73 | Q | | V| |
16+40 0.9798 1.41 | Q | | V| |
16+45 0.9886 1.27 | Q | | V |
16+50 0.9966 1.16 | Q | | V |
16+55 1.0040 1.08 | Q | | V |
17+ 0 1.0110 1.01 | Q | | V |
17+ 5 1.0176 0.96 | Q | | |V |
17+10 1.0240 0.93 | Q | | |V |
17+15 1.0302 0.91 | Q | | |V |

Page 1397 of 2028 ends

17+20 1.0363 0.88 | Q | | |V |
17+25 1.0422 0.86 | Q | | |V |
17+30 1.0479 0.83 | Q | | | V |
17+35 1.0534 0.80 | Q | | | V |
17+40 1.0588 0.78 | Q | | | V |
17+45 1.0640 0.76 | Q | | | V |
17+50 1.0691 0.74 | Q | | | V |
17+55 1.0740 0.72 | Q | | | V |
18+ 0 1.0789 0.70 | Q | | | V |
18+ 5 1.0836 0.69 | Q | | | V |
18+10 1.0882 0.67 | Q | | | V |
18+15 1.0927 0.66 | Q | | | V |
18+20 1.0972 0.65 | Q | | | V |
18+25 1.1016 0.63 | Q | | | V |
18+30 1.1059 0.62 | Q | | | V |
18+35 1.1101 0.61 | Q | | | V |
18+40 1.1142 0.60 | Q | | | V |
18+45 1.1183 0.59 | Q | | | V |
18+50 1.1223 0.58 | Q | | | V |
18+55 1.1262 0.57 | Q | | | V |
19+ 0 1.1301 0.56 | Q | | | V |
19+ 5 1.1340 0.56 | Q | | | V |
19+10 1.1377 0.55 | Q | | | V |
19+15 1.1415 0.54 | Q | | | V |
19+20 1.1451 0.53 | Q | | | V |
19+25 1.1488 0.53 | Q | | | V |
19+30 1.1523 0.52 | Q | | | V |
19+35 1.1559 0.51 | Q | | | V |
19+40 1.1594 0.51 | Q | | | V |
19+45 1.1628 0.50 | Q | | | V |
19+50 1.1662 0.50 |Q | | | V |
19+55 1.1696 0.49 |Q | | | V |
20+ 0 1.1729 0.48 |Q | | | V |
20+ 5 1.1762 0.48 |Q | | | V |
20+10 1.1795 0.47 |Q | | | V |
20+15 1.1827 0.47 |Q | | | V |
20+20 1.1859 0.46 |Q | | | V |
20+25 1.1891 0.46 |Q | | | V |
20+30 1.1922 0.46 |Q | | | V |
20+35 1.1954 0.45 |Q | | | V |
20+40 1.1984 0.45 |Q | | | V |
20+45 1.2015 0.44 |Q | | | V |
20+50 1.2045 0.44 |Q | | | V |
20+55 1.2075 0.44 |Q | | | V |
21+ 0 1.2105 0.43 |Q | | | V |
21+ 5 1.2134 0.43 |Q | | | V |
21+10 1.2163 0.42 |Q | | | V |
21+15 1.2192 0.42 |Q | | | V |
21+20 1.2221 0.42 |Q | | | V |
21+25 1.2250 0.41 |Q | | | V |

Page 1398 of 2028 ends

21+30 1.2278 0.41 |Q | | | V |
21+35 1.2306 0.41 |Q | | | V |
21+40 1.2334 0.40 |Q | | | V |
21+45 1.2361 0.40 |Q | | | V |
21+50 1.2389 0.40 |Q | | | V |
21+55 1.2416 0.40 |Q | | | V |
22+ 0 1.2443 0.39 |Q | | | V |
22+ 5 1.2470 0.39 |Q | | | V |
22+10 1.2497 0.39 |Q | | | V |
22+15 1.2523 0.38 |Q | | | V |
22+20 1.2549 0.38 |Q | | | V |
22+25 1.2576 0.38 |Q | | | V |
22+30 1.2602 0.38 |Q | | | V |
22+35 1.2627 0.37 |Q | | | V |
22+40 1.2653 0.37 |Q | | | V |
22+45 1.2678 0.37 |Q | | | V |
22+50 1.2704 0.37 |Q | | | V |
22+55 1.2729 0.37 |Q | | | V |
23+ 0 1.2754 0.36 |Q | | | V |
23+ 5 1.2779 0.36 |Q | | | V|
23+10 1.2803 0.36 |Q | | | V|
23+15 1.2828 0.36 |Q | | | V|
23+20 1.2852 0.35 |Q | | | V|
23+25 1.2877 0.35 |Q | | | V|
23+30 1.2901 0.35 |Q | | | V|
23+35 1.2925 0.35 |Q | | | V|
23+40 1.2949 0.35 |Q | | | V|
23+45 1.2972 0.34 |Q | | | V|
23+50 1.2996 0.34 |Q | | | V|
23+55 1.3019 0.34 |Q | | | V|
24+ 0 1.3043 0.34 |Q | | | V|
-----------------------------------------------------------------------

Page 1399 of 2028 ends

Inflow Runoff (peak = 6.99 cfs)
Routed Runoff (peak = 2.00 cfs)

Page 1400 of 2028 ends

Hydraulic Analysis Report
Project Data
Project Title: CVEN 164
Designer: C&V Consulting
Project Date: Monday, March 10, 2025
Project Units: U.S. Customary Units
Notes: Hydraulic Toolbox 5.3.0.0. Federal Highway Administration Detention Basin Analysis: Detention Basin Analysis
Notes:

Storage Input Parameters
Storage Capacity: Known volume (210 LF of 60” pipe)
Elevation ft Volume acre-ft

0.00 0.00

1.00 0.02

2.00 0.04

3.00 0.07

4.00 0.10

5.00 0.12

6.00 0.14

7.00 0.14

8.00 0.14
Discharge Input Parameters
Known Discharge: Pump (2cfs)
Discharge cfs

0.00 0.00

1.00 2.00

2.00 2.00

3.00 2.00

4.00 2.00

5.00 2.00

6.00 2.00

7.00 2.00

8.00 2.00

Page 1401 of 2028 ends

Known Discharge: Parkway (3’ wide)
Discharge cfs

0.00 0.00

1.00 0.00

2.00 0.00

3.00 0.00

4.00 0.00

5.00 0.00

6.00 0.00

7.00 0.85

8.00 0.85
Storage & Discharge Input Parameters
Elevation - Storage - Discharge
Elevation ft Storage acre-ft Discharge cfs

0.00 0.00 0.00

1.00 0.02 2.00

2.00 0.04 2.00

3.00 0.07 2.00

4.00 0.10 2.00

5.00 0.12 2.00

6.00 0.14 2.00

7.00 0.14 2.85

8.00 0.14 2.85
Detention Basin Input Parameters
Inflow Hydrograph
Peak Inflow Discharge: 6.990 cfs, Time to Peak: 975.00 (min), Total Inflow Volume:
56751.00 ft^3
Time (min) Discharge cfs

5.00 0.02

10.00 0.10

15.00 0.23

20.00 0.30

25.00 0.33

30.00 0.33

35.00 0.34

40.00 0.34

45.00 0.34

50.00 0.34

55.00 0.34

60.00 0.34

65.00 0.34

70.00 0.34

Page 1402 of 2028 ends

75.00 0.34

80.00 0.35

85.00 0.35

90.00 0.35

95.00 0.35
100.00 0.35
105.00 0.35
110.00 0.35
115.00 0.35
120.00 0.35
125.00 0.35
130.00 0.36
135.00 0.36
140.00 0.36
145.00 0.36
150.00 0.36
155.00 0.36
160.00 0.36
165.00 0.36
170.00 0.36
175.00 0.37
180.00 0.37
185.00 0.37
190.00 0.37
195.00 0.37
200.00 0.37
205.00 0.37
210.00 0.37
215.00 0.37
220.00 0.38
225.00 0.38
230.00 0.38
235.00 0.38
240.00 0.38
245.00 0.38
250.00 0.38
255.00 0.38
260.00 0.39
265.00 0.39
270.00 0.39
275.00 0.39
280.00 0.39
285.00 0.39
290.00 0.39
295.00 0.40
300.00 0.40
305.00 0.40
310.00 0.40
315.00 0.40
320.00 0.40

Page 1403 of 2028 ends

325.00 0.40
330.00 0.41
335.00 0.41
340.00 0.41
345.00 0.41
350.00 0.41
355.00 0.41
360.00 0.42
365.00 0.42
370.00 0.42
375.00 0.42
380.00 0.42
385.00 0.42
390.00 0.43
395.00 0.43
400.00 0.43
405.00 0.43
410.00 0.43
415.00 0.44
420.00 0.44
425.00 0.44
430.00 0.44
435.00 0.44
440.00 0.45
445.00 0.45
450.00 0.45
455.00 0.45
460.00 0.45
465.00 0.46
470.00 0.46
475.00 0.46
480.00 0.46
485.00 0.47
490.00 0.47
495.00 0.47
500.00 0.47
505.00 0.47
510.00 0.48
515.00 0.48
520.00 0.48
525.00 0.48
530.00 0.49
535.00 0.49
540.00 0.49
545.00 0.50
550.00 0.50
555.00 0.50
560.00 0.50
565.00 0.51
570.00 0.51

Page 1404 of 2028 ends

575.00 0.51
580.00 0.52
585.00 0.52
590.00 0.52
595.00 0.53
600.00 0.53
605.00 0.53
610.00 0.54
615.00 0.54
620.00 0.55
625.00 0.55
630.00 0.55
635.00 0.56
640.00 0.56
645.00 0.57
650.00 0.57
655.00 0.57
660.00 0.58
665.00 0.58
670.00 0.59
675.00 0.59
680.00 0.60
685.00 0.60
690.00 0.61
695.00 0.61
700.00 0.62
705.00 0.62
710.00 0.63
715.00 0.64
720.00 0.64
725.00 0.65
730.00 0.65
735.00 0.66
740.00 0.66
745.00 0.67
750.00 0.68
755.00 0.69
760.00 0.69
765.00 0.70
770.00 0.71
775.00 0.72
780.00 0.73
785.00 0.74
790.00 0.75
795.00 0.76
800.00 0.77
805.00 0.78
810.00 0.79
815.00 0.80
820.00 0.82

Page 1405 of 2028 ends

825.00 0.83
830.00 0.84
835.00 0.86
840.00 0.87
845.00 0.89
850.00 0.89
855.00 0.89
860.00 0.89
865.00 0.91
870.00 0.93
875.00 0.96
880.00 0.98
885.00 1.01
890.00 1.04
895.00 1.08
900.00 1.12
905.00 1.16
910.00 1.20
915.00 1.26
920.00 1.32
925.00 1.39
930.00 1.49
935.00 1.62
940.00 1.76
945.00 1.92
950.00 2.10
955.00 2.36
960.00 2.83
965.00 3.94
970.00 6.12
975.00 6.99
980.00 4.81
985.00 3.01
990.00 2.10
995.00 1.73
1000.00 1.41
1005.00 1.27
1010.00 1.16
1015.00 1.08
1020.00 1.01
1025.00 0.96
1030.00 0.93
1035.00 0.91
1040.00 0.88
1045.00 0.86
1050.00 0.83
1055.00 0.80
1060.00 0.78
1065.00 0.76
1070.00 0.74

Page 1406 of 2028 ends

1075.00 0.72
1080.00 0.70
1085.00 0.69
1090.00 0.67
1095.00 0.66
1100.00 0.65
1105.00 0.63
1110.00 0.62
1115.00 0.61
1120.00 0.60
1125.00 0.59
1130.00 0.58
1135.00 0.57
1140.00 0.56
1145.00 0.56
1150.00 0.55
1155.00 0.54
1160.00 0.53
1165.00 0.53
1170.00 0.52
1175.00 0.51
1180.00 0.51
1185.00 0.50
1190.00 0.50
1195.00 0.49
1200.00 0.48
1205.00 0.48
1210.00 0.47
1215.00 0.47
1220.00 0.46
1225.00 0.46
1230.00 0.46
1235.00 0.45
1240.00 0.45
1245.00 0.44
1250.00 0.44
1255.00 0.44
1260.00 0.43
1265.00 0.43
1270.00 0.42
1275.00 0.42
1280.00 0.42
1285.00 0.41
1290.00 0.41
1295.00 0.41
1300.00 0.40
1305.00 0.40
1310.00 0.40
1315.00 0.40
1320.00 0.39

Page 1407 of 2028 ends

1325.00 0.39
1330.00 0.39
1335.00 0.38
1340.00 0.38
1345.00 0.38
1350.00 0.38
1355.00 0.37
1360.00 0.37
1365.00 0.37
1370.00 0.37
1375.00 0.37
1380.00 0.36
1385.00 0.36
1390.00 0.36
1395.00 0.36
1400.00 0.35
1405.00 0.35
1410.00 0.35
1415.00 0.35
1420.00 0.35
1425.00 0.34
1430.00 0.34
1435.00 0.34
1440.00 0.34
Initial Storage = 0.0000 acre-ft
Detention Basin Result Parameters
Routed Hydrograph
Peak Outflow Discharge: 2.000 cfs, Time to Peak: 955.00 (min), Total Outflow Volume:
56806.82 ft^3
Time min Discharge cfs Storage acre-ft

0.00 0.00 0.000000

10.00 0.04 0.000435

15.00 0.12 0.001225

20.00 0.21 0.001864

25.00 0.27 0.002255

30.00 0.31 0.002406

35.00 0.32 0.002528

40.00 0.33 0.002602

45.00 0.34 0.002631

50.00 0.34 0.002642

55.00 0.34 0.002646

60.00 0.34 0.002647

65.00 0.34 0.002648

70.00 0.34 0.002648

75.00 0.34 0.002648

80.00 0.34 0.002696

Page 1408 of 2028 ends

85.00 0.35 0.002715

90.00 0.35 0.002722

95.00 0.35 0.002725
100.00 0.35 0.002726
105.00 0.35 0.002726
110.00 0.35 0.002726
115.00 0.35 0.002726
120.00 0.35 0.002726
125.00 0.35 0.002726
130.00 0.35 0.002774
135.00 0.36 0.002793
140.00 0.36 0.002800
145.00 0.36 0.002803
150.00 0.36 0.002804
155.00 0.36 0.002804
160.00 0.36 0.002804
165.00 0.36 0.002804
170.00 0.36 0.002804
175.00 0.36 0.002852
180.00 0.37 0.002871
185.00 0.37 0.002878
190.00 0.37 0.002880
195.00 0.37 0.002882
200.00 0.37 0.002882
205.00 0.37 0.002882
210.00 0.37 0.002882
215.00 0.37 0.002882
220.00 0.37 0.002930
225.00 0.38 0.002948
230.00 0.38 0.002956
235.00 0.38 0.002958
240.00 0.38 0.002959
245.00 0.38 0.002960
250.00 0.38 0.002960
255.00 0.38 0.002960
260.00 0.38 0.003008
265.00 0.39 0.003026
270.00 0.39 0.003033
275.00 0.39 0.003036
280.00 0.39 0.003037
285.00 0.39 0.003038
290.00 0.39 0.003038
295.00 0.39 0.003086
300.00 0.40 0.003104
305.00 0.40 0.003111
310.00 0.40 0.003114
315.00 0.40 0.003115
320.00 0.40 0.003116
325.00 0.40 0.003116
330.00 0.40 0.003164

Page 1409 of 2028 ends

335.00 0.41 0.003182
340.00 0.41 0.003189
345.00 0.41 0.003192
350.00 0.41 0.003193
355.00 0.41 0.003194
360.00 0.41 0.003241
365.00 0.42 0.003260
370.00 0.42 0.003267
375.00 0.42 0.003270
380.00 0.42 0.003271
385.00 0.42 0.003271
390.00 0.42 0.003319
395.00 0.43 0.003338
400.00 0.43 0.003345
405.00 0.43 0.003348
410.00 0.43 0.003349
415.00 0.43 0.003397
420.00 0.44 0.003416
425.00 0.44 0.003423
430.00 0.44 0.003426
435.00 0.44 0.003427
440.00 0.44 0.003475
445.00 0.45 0.003494
450.00 0.45 0.003501
455.00 0.45 0.003504
460.00 0.45 0.003505
465.00 0.45 0.003553
470.00 0.46 0.003571
475.00 0.46 0.003579
480.00 0.46 0.003581
485.00 0.46 0.003630
490.00 0.47 0.003649
495.00 0.47 0.003657
500.00 0.47 0.003659
505.00 0.47 0.003660
510.00 0.47 0.003709
515.00 0.48 0.003727
520.00 0.48 0.003734
525.00 0.48 0.003737
530.00 0.48 0.003786
535.00 0.49 0.003805
540.00 0.49 0.003812
545.00 0.49 0.003863
550.00 0.50 0.003882
555.00 0.50 0.003890
560.00 0.50 0.003893
565.00 0.50 0.003942
570.00 0.51 0.003961
575.00 0.51 0.003968
580.00 0.51 0.004019

Page 1410 of 2028 ends

585.00 0.52 0.004038
590.00 0.52 0.004046
595.00 0.52 0.004097
600.00 0.53 0.004116
605.00 0.53 0.004124
610.00 0.53 0.004174
615.00 0.54 0.004194
620.00 0.54 0.004249
625.00 0.55 0.004271
630.00 0.55 0.004279
635.00 0.55 0.004330
640.00 0.56 0.004350
645.00 0.56 0.004405
650.00 0.57 0.004427
655.00 0.57 0.004435
660.00 0.57 0.004486
665.00 0.58 0.004506
670.00 0.58 0.004561
675.00 0.59 0.004582
680.00 0.59 0.004638
685.00 0.60 0.004660
690.00 0.60 0.004716
695.00 0.61 0.004738
700.00 0.61 0.004794
705.00 0.62 0.004816
710.00 0.62 0.004872
715.00 0.63 0.004942
720.00 0.64 0.004968
725.00 0.64 0.005027
730.00 0.65 0.005049
735.00 0.65 0.005106
740.00 0.66 0.005127
745.00 0.66 0.005184
750.00 0.67 0.005253
755.00 0.68 0.005328
760.00 0.69 0.005357
765.00 0.69 0.005416
770.00 0.70 0.005486
775.00 0.71 0.005561
780.00 0.72 0.005638
785.00 0.73 0.005715
790.00 0.74 0.005793
795.00 0.75 0.005871
800.00 0.76 0.005949
805.00 0.77 0.006027
810.00 0.78 0.006105
815.00 0.79 0.006183
820.00 0.80 0.006308
825.00 0.82 0.006405
830.00 0.83 0.006490

Page 1411 of 2028 ends

835.00 0.84 0.006618
840.00 0.86 0.006716
845.00 0.87 0.006849
850.00 0.88 0.006900
855.00 0.89 0.006920
860.00 0.89 0.006928
865.00 0.90 0.007026
870.00 0.91 0.007160
875.00 0.93 0.007355
880.00 0.96 0.007526
885.00 0.98 0.007735
890.00 1.01 0.007960
895.00 1.04 0.008238
900.00 1.08 0.008536
905.00 1.12 0.008843
910.00 1.16 0.009152
915.00 1.20 0.009559
920.00 1.26 0.010002
925.00 1.32 0.010508
930.00 1.39 0.011182
935.00 1.49 0.012063
940.00 1.61 0.013073
945.00 1.75 0.014227
950.00 1.91 0.015534
955.00 2.00 0.018013
960.00 2.00 0.023729
965.00 2.00 0.037090
970.00 2.00 0.065465
975.00 2.00 0.099831
980.00 2.00 0.119184
985.00 2.00 0.126140
990.00 2.00 0.126828
995.00 2.00 0.124969
1000.00 2.00 0.120905
1005.00 2.00 0.115878
1010.00 2.00 0.110093
1015.00 2.00 0.103757
1020.00 2.00 0.096939
1025.00 2.00 0.089776
1030.00 2.00 0.082407
1035.00 2.00 0.074900
1040.00 2.00 0.067187
1045.00 2.00 0.059335
1050.00 2.00 0.051278
1055.00 2.00 0.043013
1060.00 2.00 0.034611
1065.00 2.00 0.026071
1070.00 2.00 0.017393
1075.00 1.77 0.013781
1080.00 1.12 0.010890

Page 1412 of 2028 ends

1085.00 0.86 0.009724
1090.00 0.75 0.009177
1095.00 0.70 0.008917
1100.00 0.67 0.008769
1105.00 0.65 0.008617
1110.00 0.64 0.008510
1115.00 0.62 0.008421
1120.00 0.61 0.008338
1125.00 0.60 0.008259
1130.00 0.59 0.008180
1135.00 0.58 0.008102
1140.00 0.57 0.008024
1145.00 0.56 0.007994
1150.00 0.56 0.007934
1155.00 0.55 0.007864
1160.00 0.54 0.007789
1165.00 0.53 0.007759
1170.00 0.53 0.007700
1175.00 0.52 0.007630
1180.00 0.51 0.007603
1185.00 0.51 0.007544
1190.00 0.50 0.007522
1195.00 0.50 0.007465
1200.00 0.49 0.007396
1205.00 0.48 0.007369
1210.00 0.48 0.007310
1215.00 0.47 0.007288
1220.00 0.47 0.007232
1225.00 0.46 0.007210
1230.00 0.46 0.007201
1235.00 0.46 0.007150
1240.00 0.45 0.007130
1245.00 0.45 0.007075
1250.00 0.44 0.007054
1255.00 0.44 0.007045
1260.00 0.44 0.006994
1265.00 0.43 0.006975
1270.00 0.43 0.006919
1275.00 0.42 0.006898
1280.00 0.42 0.006890
1285.00 0.42 0.006839
1290.00 0.41 0.006819
1295.00 0.41 0.006811
1300.00 0.41 0.006760
1305.00 0.40 0.006741
1310.00 0.40 0.006733
1315.00 0.40 0.006730
1320.00 0.40 0.006681
1325.00 0.39 0.006663
1330.00 0.39 0.006655

Page 1413 of 2028 ends

1335.00 0.39 0.006605
1340.00 0.38 0.006585
1345.00 0.38 0.006577
1350.00 0.38 0.006575
1355.00 0.38 0.006526
1360.00 0.37 0.006507
1365.00 0.37 0.006499
1370.00 0.37 0.006497
1375.00 0.37 0.006495
1380.00 0.37 0.006447
1385.00 0.36 0.006429
1390.00 0.36 0.006421
1395.00 0.36 0.006419
1400.00 0.36 0.006370
1405.00 0.35 0.006351
1410.00 0.35 0.006344
1415.00 0.35 0.006341
1420.00 0.35 0.006340
1425.00 0.35 0.006292
1430.00 0.34 0.006273
1435.00 0.34 0.006266
1440.00 0.34 0.006263
1445.00 0.24 0.004638
1450.00 0.09 0.004009
1455.00 0.04 0.003766
1460.00 0.01 0.003672
1465.00 0.01 0.003636
1470.00 0.00 0.003622

Page 1414 of 2028 ends

Preliminary Hydrology Study
City of Yorba Linda, County of Orange

APPENDIX D
Hydraulic Analysis

Page 1415 of 2028 ends

Channel Report
Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Tuesday, Mar 11 2025 Parkway Drain Q100
Rectangular
Bottom Width (ft) = 3.00
Total Depth (ft) = 0.33
Invert Elev (ft) = 1.00
Slope (%) = 2.00
N-Value = 0.015
Calculations
Compute by: Known Q
Known Q (cfs) = 2.85
Highlighted
Depth (ft) = 0.21
Q (cfs) = 2.850
Area (sqft) = 0.63
Velocity (ft/s) = 4.52
Wetted Perim (ft) = 3.42
Crit Depth, Yc (ft) = 0.31
Top Width (ft) = 3.00
EGL (ft) = 0.53
0 .5 1 1.5 2 2.5 3 3.5 4
Elev (ft) Depth (ft) Section

0.75 -0.25

1.00 0.00

1.25 0.25

1.50 0.50

1.75 0.75

2.00 1.00
Reach (ft)

Page 1416 of 2028 ends

Channel Report
Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Tuesday, Mar 4 2025 Offsite Runon Q100
Rectangular
Bottom Width (ft) = 1.50
Total Depth (ft) = 0.50
Invert Elev (ft) = 1.00
Slope (%) = 2.12
N-Value = 0.015
Calculations
Compute by: Known Q
Known Q (cfs) = 3.15
Highlighted
Depth (ft) = 0.37
Q (cfs) = 3.150
Area (sqft) = 0.55
Velocity (ft/s) = 5.68
Wetted Perim (ft) = 2.24
Crit Depth, Yc (ft) = 0.50
Top Width (ft) = 1.50
EGL (ft) = 0.87
0 .5 1 1.5 2 2.5
Elev (ft) Depth (ft) Section

0.75 -0.25

1.00 0.00

1.25 0.25

1.50 0.50

1.75 0.75

2.00 1.00
Reach (ft)

Page 1417 of 2028 ends

Preliminary Hydrology Study
City of Yorba Linda, County of Orange

APPENDIX E
Reference Materials

Page 1418 of 2028 ends

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PROPOSED SITE

Page 1423 of 2028 ends

Preliminary Water Quality
Management Plan
(PWQMP)
Project Name:

TTM 19389
19081 YORBA LINDA BLVD
YORBA LINDA, CA 92886
Prepared for:

CITY VENTURES HOMEBUILDING
3121 MICHELSON DRIVE, SUITE 150
IRVINE, CA 92612
(949) 258-7540
Prepared by:

C&V CONSULTING, INC.

Engineer DANE MCDOUGALL, P.E.

Registration No. C 80705
9830 IRVINE CENTER DRIVE
IRVINE, CA 92618
(949) 916-3800
Prepared: MARCH 2025

Page 1424 of 2028 ends

Project Owner’s Certification
Permit/Application No. TBD Grading Permit No. TBD
Tract/Parcel Map No. TTM 19389 Building Permit No. TBD
CUP, SUP, and/or APN (Specify Lot Numbers if Portions of Tract) APN 323-081-35 This Preliminary Water Quality Management Plan (WQMP) has been prepared for City Ventures Homebuilding, LLC by C&V Consulting, Inc. The WQMP is intended to comply with the requirements of the local NPDES Stormwater Program requiring the preparation of the plan and with the requirements of the California Environmental Quality Act (CEQA) to address and assess the impacts of storm water runoff and propose mitigation recommendations as part the environmental element of the entitlement review of the project.

The undersigned, while it owns the subject property, is responsible for the implementation of the provisions of the Final WQMP and will ensure that this plan is amended as appropriate to reflect up-to-date conditions on the site consistent with the current Orange County Drainage Area Management Plan (DAMP) and the intent of the non-point source NPDES Permit for Waste Discharge Requirements for the County of Orange, Orange County Flood Control District and the incorporated Cities of Orange County within the Santa Ana Region. Once the undersigned transfers its interest in the property, its successors-in-interest shall bear the aforementioned responsibility to implement and amend the WQMP. An appropriate number of approved and signed copies of this document shall be available on the subject site in perpetuity.

Owner: Patrick Chien
Title Director of Development
Company City Ventures Homebuilding, LLC
Address 3121 Michelson Drive, Suite 150, Irvine, Ca 92612 Email [email protected]
Telephone # 949.258.7540
Signature Date

Page 1425 of 2028 ends

Section I
City Ventures Homebuilding, LLC Table of Contents
Table of Contents Page No.

Section I Discretionary Permit(s) and Water Quality Conditions ..................................... 3 Section II Project Description .......................................................................................... 4 Section III Site Description ........................................................................................... 10 Section IV Best Management Practices (BMPs) ............................................................. 16 Section V Inspection/Maintenance Responsibility for BMPs .......................................... 30 Section VI Site Plan and Drainage Plan ......................................................................... 34 Section VII Educational Materials .................................................................................. 35 Attachments
Attachment A . ......................................................................... Preliminary WQMP Exhibit Attachment B . ........................................................................ TGD Figures & Worksheets Attachment C . ................................................................................................... Site BMPs Attachment D . ................................................................................................... O&M Plan Attachment E . ................................................................................... Geotechnical Report Attachment F . ................................................................................. Educational Materials

Page 1426 of 2028 ends

Preliminary Water Quality Management Plan (PWQMP)
VTTM 19389, Yorba Linda

City Ventures Homebuilding, LLC Section I
CVEN-164 Preliminary WQMP_Yorba Linda Page 3
Section I Discretionary Permit(s) and
Water Quality Conditions
Project Infomation
Permit/Application No. Tract/Parcel Map No. TTM 19389, Lot 1 Additional Information/
Comments:
19081 Yorba Linda Blvd
APN: 323-081-35
This Preliminary WQMP is intended to serve as a part of the environmental documentation for the project as required under CEQA.

Water Quality Conditions
Water Quality Conditions
(list verbatim)
Water Quality Conditions of Approval have not been provided at this time.

Watershed-Based Plan Conditions
Provide applicable
conditions from
watershed - based plans
including WIHMPs and
TMDLS.
n/a

Page 1427 of 2028 ends

Preliminary Water Quality Management Plan (PWQMP)
TTM 19389

City Ventures Homebuilding, LLC Section II
CVEN-164 Preliminary WQMP_Yorba Linda Page 4
Section II Project Description
II.1 Project Description
Description of Proposed Project
Development Category
(Verbatim from WQMP):

All significant redevelopment projects, where significant redevelopment is defined as projects that include the addition or replacement of 5,000 square feet or more of impervious surface on a developed site. Redevelopment does not include routine maintenance activities that are conducted to maintain original line and grade, hydraulic capacity, original purpose of the facility, or emergency redevelopment activity required to protect public health and safety.

If the redevelopment results in the addition or replacement of less than 50 percent of the impervious area on-site and the existing development was not subject to WQMP requirement, the numeric sizing criteria discussed in Section

7.II-2.0 only applies to the addition or the replacement area. If the addition or replacement accounts for 50 percent or more of the impervious area, the Project WQMP requirements apply to the entire development.

Project Area (ft2):
115320.155 sft
Number of Dwelling Units: 62 SIC Code: n/a
Narrative Project
Description:

The total project area consists of approximately 2.65 acres and is located at 19081 Yorba Linda Blvd in the city of Yorba Linda, California. The existing site consists of two (2) single family homes with sheds dispersed throughout the site.

The existing impervious cover is approximately 18764.83 sft and the remainder of the site is undeveloped and covered in soil, trees, and shrubs. The existing buildings and pavement will be demolished by City Ventures Homebuilding as part of this development.

The site is surrounded by chain link fence and vinyl fencing along with a short 1- foot to 2-foot low block wall on the northern portion of the site. There is one existing concrete driveway entrance along Yorba Linda Blvd provided primary access to the site. The elevation of the site ranges from 439 to 455 feet above sea level.

The project proposes the construction of sixty-two (62) multi‐family condominium units within twelve (12) buildings with open space areas that will incorporate landscaping to the maximum extent feasible. The project proposes onsite private drive aisles, parking areas, hardscaping, and landscaping, which can be accessed from the main entrance from the public right-of-way of Yorba Linda Blvd. Drive aisles and parking areas will be asphalt concrete pavement, and sidewalk areas will be Portland concrete

Page 1428 of 2028 ends

Preliminary Water Quality Management Plan (PWQMP)
TTM 19389

City Ventures Homebuilding, LLC Section II
CVEN-164 Preliminary WQMP_Yorba Linda Page 5
cement (PCC). Landscaping, including vegetation and trees, will be incorporated into open space areas. Open space areas and landscape areas will be maintained by an appointed property management company. Long-term maintenance will be managed by an appointed Homeowner’s Association selected by City Ventures Homebuilding, LLC.

The project will be serviced by an onsite public water system and onsite public sanitary sewer system. The proposed public water system will have one point of connection to the existing city domestic water line within Yorba Linda Blvd.

The proposed public sewer system will be gravity fed to one point of connection to the city sanitary sewer main within Yorba Linda Blvd.

Refer to the separately prepared Preliminary Hydrology & Hydraulic Study by C&V Consulting, Inc. for additional information related to existing and proposed hydrologic conditions.

Project Area
Pervious Impervious
Area
(acres or sq ft)
Percentage
Area
(acres or sq ft)
Percentage
Pre-Project Conditions 2.22 ac 84% 0.43 ac 16%
Post-Project Conditions 0 0% 2.65 100%
Drainage
Patterns/Connections
Stormwater runoff generally sheet flows overland in the southwesterly direction until it enters the right-of-way at Yorba Linda Blvd via the driveway.

Once runoff enters Yorba Linda Blvd, it is conveyed via curb and gutter west to a catch basin at the intersection of Yorba Linda Blvd and Ohio Street, approximately 120 feet west of the project.

The site experiences offsite runon along the northern property lines. There is an equestrian trail that runs along the northern property line that drains to the site’s northwest corner. The residential lots north of the equestrian trail and a portion of Lynn Lane drains to the northwest corner of the site as well.

Runoff from the site discharges into the Santa Ana River, ultimately discharging into the Pacific Ocean. The site is located within the Santa Ana River Watershed per the Orange County Flood Control District (OCFCD) Drainage System Map No. 08
All existing onsite storm drain connections, piping and inlets will be demolished and capped at the right-of-way as part of this development’s construction.

In the proposed condition, site runoff will be captured by two (2) proposed sump curb inlet Modular Wetland (MWS) Units and two (2) proposed grate

Page 1429 of 2028 ends

Preliminary Water Quality Management Plan (PWQMP)
TTM 19389

City Ventures Homebuilding, LLC Section II
CVEN-164 Preliminary WQMP_Yorba Linda Page 6
Drainage
Patterns/Connections
(cont.)
inlets. The MWS units will treat the required water quality treatment volume.

When the water quality treatment flow rate is exceeded, runoff will internally bypass in the MWS units and be directed through the proposed underground storm drain system and into underground detention pipes. Runoff will be directed from the detention pipes into a proposed sump pump located at the project entrance which will discharge runoff through a proposed parkway drain into Yorba Linda Blvd at pre development flow rates. During larger storm events, runoff will pond at the proposed catch basins near the entry driveway and discharge into the public right-of-way of Yorba Linda Blvd.

Upon entering surrounding streets, site stormwater runoff will follow the historic drainage path to the Santa Ana River and ultimately the Pacific Ocean.

The Connector Pipe Screen (CPS) devices will be located onsite upstream of the proposed storm drain overflow pipes to mitigate the required full trash captures requirements.

According to the Federal Emergency Management Agency (FEMA), FIRM rate map Number 06059C0068J, revised December 3, 2009, the site is located within the flood zone as follows: Zone X – “Area of Minimal Flood Hazard.” Refer to the Preliminary WQMP Exhibit in Attachment B of this report for the Modular Wetland System locations.

II.2 Potential Stormwater Pollutants

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Preliminary Water Quality Management Plan (PWQMP)
TTM 19389

City Ventures Homebuilding, LLC Section II
CVEN-164 Preliminary WQMP_Yorba Linda Page 7
Pollutants of Concern
Pollutant
Circle One:

E=Expected to
be of concern
N=Not Expected
to be of concern
Additional Information and Comments
Suspended-Solid/ Sediment E N Expected due to residential use and proposed landscaping per Table 2.1 of the TGD.

Nutrients E N Expected due to residential use and proposed landscaping per Table 2.1 of the TGD.

Heavy Metals E N Not tributary by Attached Residential Developments per Table 2.1 of the TGD.

Pathogens (Bacteria/Virus) E N Expected due to residential use and proposed parking areas/ drive aisle per Table 2.1 of the TGD.

Pesticides E N Expected due to residential use and proposed landscaping per Table 2.1 of the TGD.

Oil and Grease E N Expected due to residential use and proposed parking areas/ drive aisle per Table 2.1 of the TGD.

Toxic Organic Compounds E N Expected due to residential use and proposed parking areas/ drive aisle per Table 2.1 of the TGD.

Trash and Debris E N Expected due to residential use per Table 2.1 of the TGD.

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Preliminary Water Quality Management Plan (PWQMP)
TTM 19389

City Ventures Homebuilding, LLC Section II
CVEN-164 Preliminary WQMP_Yorba Linda Page 8
II.3 Hydrologic Conditions of Concern
No – Show map
Yes – Describe applicable hydrologic conditions of concern below. Refer to Section 2.2.3 in the TGD.

Per the TGD Figure 3, Susceptibility Analysis of Santa Ana River dated February 2013, the project site is not indicated as a potential area of erosion, habitat, and physical structure susceptibility. The project site drains only through engineered/stabilized channels prior to discharging to the Pacific Ocean.

Therefore, HCOCs do not apply to this project. Refer to Attachment B for a the TGD Figure 2.

Page 1432 of 2028 ends

Preliminary Water Quality Management Plan (PWQMP)
TTM 19389

City Ventures Homebuilding, LLC Section II
CVEN-164 Preliminary WQMP_Yorba Linda Page 9
II.4 Post Development Drainage Characteristics
Post–development drainage will be consistent with a proposed attached Multi-Family Residential project.

The tributary areas and direction stormwater runoff for the proposed site are delineated within the Preliminary WQMP Exhibit based on the preliminary grading and drainage design. Refer to the Preliminary WQMP Exhibit in Attachment B of this report.

Currently, the site drains overland from the northeast corner to the southwest corner of the site and overflows over the existing driveway into the public right-of-way of Yorba Linda Blvd.

In the proposed condition, site runoff will be captured by two (2) proposed sump curb inlet Modular Weltand (MWS) units and two (2) proposed grate inlets. The MWS units will treat the runoff according to water quality requirements. When the water quality treatment flow rate is exceeded, runoff will be directed through the proposed underground storm drain system. The MWS units have an internal bypass system so when the water quality design flow rate is exceeded runoff will be directed over the internal weir and into underground storm drain facilities. All runoff will be directed into a proposed underground detention system which will feed a storm drain sump pump located at the project entrance which will discharge runoff through a proposed parkway drain into Yorba Linda Blvd at pre developed flow rates. During larger storm events, runoff will pond at the proposed catch basins near the entry driveway and discharge into the public right-of-way of Yorba Linda Blvd. Upon entering surrounding streets, site stormwater runoff will follow the historic drainage path to the Santa Ana River/ Pacific Ocean.

II.5 Property Ownership/Management
The property is currently owned by City Ventures Homebuilding, LLC. The Owner will be responsible for the long-term maintenance of the project’s storm water facilities (MWS Facilities, Stormwater Sump Pump, Parkway Drain) and conformance to this WQMP after construction is complete.

A Notice of Transfer of Responsibility located in Attachment E of this report and should be executed as part of any ownership transfer after construction is complete.

Stormwater Quality infrastructure will not be transferred to any Public Agencies.

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Section III Site Description
III.1 Physical Setting
Name of Planned
Community/Planning Area
(if applicable)
NA
Location/Address
19081 Yorba Linda Blvd
Yorba Linda, Ca 92886
General Plan Land Use
Designation Residential – Medium Low
Zoning Residential Estate (RS)
Acreage of Project Site 2.647 ac
Predominant Soil Type Soil Type C per NRCS Hydrology Soil Groups, TGD Figure XVI-2a. Refer to Attachment B.

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III.2 Site Characteristics
Precipitation Zone 0.9” (Refer to Figure XVI-1 of the TGD located in Attachment B of this report for reference of rainfall zone.)
Topography
The site generally slopes from the northeast corner to the southwest corner with elevations ranging from approximately 455.5 to 438 above mean sea level.

Drainage
Patterns/Connections
Stormwater runoff generally sheet flows overland in the southwesterly direction until it enters the right-of-way at Yorba Linda Blvd via the driveway. Once runoff enters Yorba Linda Blvd, it is conveyed via curb and gutter west to a catch basin at the intersection of Yorba Linda Blvd and Ohio Street.

The site experiences offsite runon along the northern property line. There is an equestrian trail that runs along the northern property line that drains to the site’s northwest corner. The residential lots north of the equestrian trail and a portion of Lynn Lane drains to the northwest corner of the site as well.

Soil Type, Geology, and
Infiltration Properties
Per the Geotechnical Engineering Investigation prepared by Alta California Geotechnical Inc., dated January 2025, the site’s geotechnical properties are described as the following:
“Based on Alta’s review of geologic literature and our subsurface investigation the project site is underlain by Pleistocene age very old alluvial fan deposits (Dibblee, 2001). The following is a brief description of this geologic unit encountered during this investigation. Very Old Alluvial Fan Deposits (Map symbol Qvof)”
“The very old alluvial fan deposits within the site consists primarily of inter-lensed silty sand, clayey sand, sand and gravelly sand that is slightly moist to moist and dense to very dense below. This unit was encountered up to 51 feet below ground surface (bgs).”
“From a geotechnical perspective, allowing storm water to infiltrate the onsite soil in concentrated areas increases the potential for settlement, liquefaction, and water-related damage to structures/improvements, such as wet slabs or pumping subgrade, and should be avoided where possible. If infiltration systems are required on this site, care should be taken in designing systems that control the storm water as much as possible.

Preliminary infiltration testing was as part of Alta’s geotechnical investigation. “
Refer to Attachment D of this report for a copy of the Geotechnical report.

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Site Characteristics (continued)
Hydrogeologic
(Groundwater)
Conditions
Per the Geotechnical Engineering Investigation prepared by Alta California Geotechnical Inc., dated January 2025, the site’s groundwater properties are described as the following:
“Groundwater was not encountered in any borings during Alta’s recent investigation, to a depth of roughly 51 feet bgs. No nearby groundwater well data is available. “
Refer to Attachment D of this report for a copy of the Geotechnical report.

Geotechnical Conditions
(relevant to infiltration)
Per the Geotechnical Engineering Investigation prepared by Alta California Geotechnical Inc., dated January 2025, the site’s geotechnical condition relevant to infiltration are described as the following:

Infiltration testing was performed by Alta on December 10, 2024, utilizing percolation methods in accordance with County of Orange Storm Water Standards. Percolation rates were converted to infiltration rates utilizing the Porchet method. The resulting field infiltration rates, with no factor of safety, are presented below in Table 3-1. Recommendations for infiltration BMP design are presented in Section 6.3.

Table 3-1 Summary of Infiltration Testing (No Factor of Safety) Test Designation P-1 P-2
Approximate Depth of Test 10.0 feet 5.0 feet
Final Time Interval 30 minutes 30 minutes
Tested Infiltration Rate 0.8 in/hr 0.1 in/hr
Refer to Attachment D of this report for a copy of the Geotechnical report
Off-Site Drainage
The site experiences offsite runon along the northern property lines. There is an equestrian trail that runs along the northern property line that drains to the site’s northwest corner. The residential lots north of the equestrian trail and a portion of Lynn Lane drains to the northwest corner of the site as well.

Offsite run-on is proposed to be conveyed through the site in an open concrete U-Channel along the western property line. These flows will be conveyed through the site, separate from onsite flows generated by the proposed development. These flows will discharge into the public- right of way of Yorba Linda Blvd through a parkway drain. Offsite and onsite runoff flows will not co-mingle prior to discharge from the site.

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Utility and Infrastructure
Information
All stormwater flows overland in a southern direction towards the public right-of-way of Yorba Linda Blvd.

Storm drain will be private for the proposed site. Domestic Water and Sanitary Sewer will be public and owned/ maintained by the City of Yorba Linda. Sanitary sewer will have connection point to the existing system within Yorba Linda Blvd. All utilities are proposed to be underground.

III.3 Watershed Description
Receiving Waters
Site Runoff drains towards the southwestern corner of the site and discharges into the Santa Ana River and ultimately the Pacific Ocean.

The site is located within the Santa Ana Watershed.
303(d) Listed Impairments Santa Ana River Reach 2 – Indicator Bacteria Applicable TMDLs
Santa Ana River Reach 2 – Alachlor | Atrazine | Azinphos-methyl (Guthion) | Carbaryl | Carbofuran | Chlorpyrifos | DDE
(Dichlorodiphenyldichloroethylene) | Diazinon | Dieldrin | Disulfoton | Malathion | Methyl Parathion | Molinate | Simazine | Thiobencarb/Bolero, Cadmium, Copper, Indicator Bacteria, Lead Santa Ana River Reach 1 – Fecal Coliform
Pollutants of Concern for
the Project
Suspended Solid/Sediments, Nutrients, Pathogens (Bacteria/Virus), Pesticides, Toxic Organic Compounds
Environmentally Sensitive
and Special Biological
Significant Areas
The project is not located within any known Environmentally Sensitive Areas (ESA) or Areas of Special Biological Significance (ASBS) per the Watershed E: Santa Ana River Environmentally Sensitive Area Map provided within Attachment B.

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Section IV Best Management Practices (BMPs)
IV. 1 Project Performance Criteria
(NOC Permit Area only) Is there an approved WIHMP or equivalent for the project area that includes more stringent LID feasibility criteria or if there are opportunities identified for implementing LID on regional or sub-regional basis?
YES NO
If yes, describe WIHMP
feasibility criteria or
regional/sub-regional LID
opportunities.
n/a

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Project Performance Criteria (continued)
If HCOC exists, list
applicable
hydromodification
control performance
criteria (Section 7.II2.4.2.2 in MWQMP)
Per 7.II-2.4.2.2 of the MWQMP, HCOC exists for when the post-construction time of concentration decreases beyond 5% of a 2-year storm event and volume of storm water increases beyond 5% of a 2-year storm event thus potentially increasing the downstream erosion and adversely impacts on physical structure, aquatic, and riparian habitat. However, a site that infiltrates at least the runoff from a two-year storm event does not have an HCOC
If the excess volume cannot feasibly be retained, then retain the excess volume from the two-year runoff event to the maximum extent possible and implement on-site hydromodification controls such that post development runoff two-year peak flow rate is not greater than 110 percent of the predevelopment runoff two-year peak flow rate.

List applicable LID
performance criteria
(Section 7.II-2.4.3
from MWQMP)
According to Section 7.II-2.4.3 of the MWQMP, the available LID Treatment BMPs to be utilized in reducing the post-development impacts include infiltration, harvest, and use, evapotranspiration, or biotreat/biofilter, the 85th percentile of a 24-hour storm event.

This project proposes to utilize Biotreatment BMPs to treat the required stormwater runoff
List applicable
treatment control
BMP performance
criteria (Section 7.II3.2.2 from
MWQMP)
If it is not feasible to meet LID performance criteria through retention and/or biotreatment provided on-site or at a sub-regional/regional scale, then treatment control BMPs shall be provided on-site or off-site prior to discharge to waters of the US. Since the project proposes to satisfy LID performance criteria, therefore treatment control performance criteria are also fully satisfied. Sizing of treatment control BMPs (Biofiltration Systems) shall be based flow-based for the area being redeveloped to medium and high effectiveness for reducing the primary pollutants of concern, which will be considered in compliance.

This project proposes to utilize Biotreatment BMPs to treat the required storm water runoff. Refer to Attachment C for manufacturer’s specifications for the proposed Biofiltration BMP. Refer to Section IV.3.4, Biotreatment BMPs for additional information regarding BMP selection.

Calculate LID
design storm
capture volume for
Project.

Biotreatment BMPs will be utilized for onsite treatment of the water quality design flow rate. The proposed project residential site will generate a total DCV of 7,7623 cf.

DMA A1: Vdesign = (0.9)(0.9)(1.90 ac)(43,560 sf/ac)(1 ft/12 in) = 5,586.57 cf DMA A2: Vdesign = (0.9)(0.9)(0.74 ac)(43,560 sf/ac)(1 ft/12 in)= 2,175.8 cf Due to infiltration being infeasible at the site, biofiltration vaults will treat the required water quality design flow rate. The site will generate a total water quality design flowrate of 0.618 cfs.

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DMA A1: Qdesign = (0.90)(0.26 in/hr)(1.90 ac) = 0.445 cfs DMA A2: Qdesign = (0.90)(0.26 in/hr)(0.74 ac) = 0.173 cfs See Attachment A of this report for DCV and treatment flow rate calculations.

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IV.2. SITE DESIGN AND DRAINAGE PLAN
The site proposes two (2) Drainage Management Areas (DMAs) as indicated on the WQMP Exhibit. The DMAs are based on the Grading and Drainage design. Each DMA will have an area drain system to collect and convey runoff from landscape, surface, and roof drainage to the proposed treatment devices. Pervious coverages located throughout the site will promote impervious area dispersion from roof and sidewalk runoff.

Street surface runoff will be collected and conveyed through curb inlet catch Modular Wetland (MWS) units or grated inlet catch basins. The MWS units are Biofiltration vaults for water quality treatment. During larger storm events when the proposed biofiltration BMPs are at capacity, stormwater will bypass within the units and be directed into underground storm drain detention system that feeds a stormwater sump pump.

The sump pump will discharge runoff through a proposed parkway drain at pre-development flow rates.

When the detention system and sump pump are at capacity, runoff will pond at the proposed catch basin near the project entry and flow over the proposed driveway and into the public right of way of Yorba Linda Blvd. The proposed sump pump will also consist of an overflow pipe that runoff will enter and be discharged through the proposed parkway drain into the public right of way of Yorba Linda Blvd.

The Modular Wetland System (MWS) Biofiltration vaults are designed to provide a 3-phase treatment train.

Initially, when the stormwater enters the system, a trash rack, filter media and settling chamber will capture large trash/ debris and sediment in the stormwater before entering the planting media. This system is designed to treat stormwater flow horizontally. Before the stormwater enters the planting or “wetland” chamber, the runoff flows through the 2nd phase, a pre-filter cartridge which captures fines TSS, metals, nutrients, and bacteria. The pre-filter chamber eliminates additional maintenance of the planting area. The wetland chamber is the 3rd phase of the system which provides final treatment through a combination of physical, chemical, and biological processes. Refer to Section IV.3.4 of this report for sizing information of the Biofiltration Vaults.

Connector Pipe Screen (CPS) devices will be located onsite upstream of the proposed storm drain overflow pipes to mitigate the required full trash captures requirements.

Refer to Worksheet B in Attachment A of this report.

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IV.3 LID BMP SELECTION AND PROJECT CONFORMANCE ANALYSIS IV.3.1 Hydrologic Source Controls
Name Included?
Localized on-lot infiltration
Impervious area dispersion (e.g. roof top
disconnection)
Street trees (canopy interception)
Residential rain barrels (not actively managed)
Green roofs/Brown roofs
Blue roofs
Impervious area reduction (e.g. permeable
pavers, site design)
Other:
* HSC BMPs are not required since the site has been exempted based on HCOC map. Refer to Attachment B of this report for additional information

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IV.3.2 Infiltration BMPs
Name Included?
Bioretention without underdrains
Rain gardens
Porous landscaping
Infiltration planters
Retention swales
Infiltration trenches
Infiltration basins
Drywells
Subsurface infiltration galleries
French drains
Permeable asphalt
Permeable concrete
Permeable concrete pavers
Other:

Other:

Infiltration BMPs will not be utilized and have been determined to be infeasible for this site due to low infiltration rates. Biotreatment BMPs will be utilized to provide the required treatment flow rates.

Refer to Table 2.7 Infiltration BMP Feasibility Worksheet located within Attachment A for additional information.

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IV.3.3 Evapotranspiration, Rainwater Harvesting BMPs
Name Included?
All HSCs; See Section IV.3.1
Surface-based infiltration BMPs
Biotreatment BMPs
Above-ground cisterns and basins
Underground detention
Other:

Other:

Evapotranspiration, Rainwater Harvesting BMPs will not be utilized and have been determined to be infeasible for this site due to development type, density and available amount of landscaped area for irrigation purposes. Refer to Worksheet J for feasibility calculations within Attachment A of this report. Biotreatment BMPs will be utilized to provide the required treatment flow rates.

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IV.3.4 Biotreatment BMPs
Name Included?
Bioretention with underdrains
Stormwater planter boxes with
underdrains
Rain gardens with underdrains
Constructed wetlands
Vegetated swales
Vegetated filter strips
Proprietary vegetated biotreatment
systems
Wet extended detention basin
Dry extended detention basins
Other:

Other:

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Proprietary Vegetated Biotreatment Systems:

Modular Wetland System (MWS) Biofiltration curb inlets will be utilized to capture and treat the stormwater runoff before leaving the site. The MWS Biofiltration system utilizes a 3-phase treatment train by collecting the stormwater runoff in a Pre-Treatment Chamber, Planting or “Wetland” Chamber and Discharge Chamber. Treated storm water runoff will be pumped and discharged into a proposed parkway drain on Yorba Linda Blvd.

Refer to Attachment C for additional manufacturer’s BMP information.

The MWS Biofiltration curb inlet systems were sized based on the treatment flow rate method per the Orange County Technical Guidance Document worksheets. Refer to Worksheet D in Attachment A for calculations.

DMA Area
(ac)
Required
Treatment, Q (cfs) MWS Model Treatment Capacity, Q (cfs) DMA A1 1.82 0.445 MWS-L-8-16 0.462
DMA A2 0.83 0.173 MWS-L-8-8 0.195
*A project-specific Modular Wetlands System (MWS) Biofiltration curb inlet detail will be provided during final engineering. Refer to additional manufacturer sizing information located within Attachment C of this report.

Treated storm water runoff discharging from the MWS Biofiltration vault will enter a proposed stormwater sump pump system designed to meet the treatment flow rate. Pump sizing and details will provided during final engineering.

Refer to Section V and Attachment E within this report for the project-specific Operation and Maintenance (O&M) Plan.

IV.3.5 Hydromodification Control BMPs
Hydromodification Control BMPs
BMP Name BMP Description
n/a n/a

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IV.3.6 Regional/Sub-Regional LID BMPs
Regional/Sub-Regional LID BMPs
n/a
IV.3.7 Treatment Control BMPs
Treatment Control BMPs
BMP Name BMP Description
Connector Pipe Screen (CPS) Device
Connector Pipe Screen (CPS) devices will be utilized prior to the proposed overflow storm drain pipe to provide full trash capture requirements.

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IV.3.8 Non-structural Source Control BMPs
Non-Structural Source Control BMPs
Identifier Name
Check One
If not applicable, state brief
reason Included Not
Applicable
N1 Education for Property Owners,
Tenants, and Occupants
N2 Activity Restrictions
N3 Common Area Landscape
Management
N4 BMP Maintenance
N5 Title 22 CCR Compliance (How
development will comply)
N6 Local Industrial Permit
Compliance Residential development
N7 Spill Contingency Plan
N8 Underground Storage Tank
Compliance Residential development
N9
Hazardous Materials Disclosure
Compliance
Residential development,
no hazardous materials
proposed
N10 Uniform Fire Code
Implementation
N11 Common Area Litter Control
N12 Employee Training
N13 Housekeeping of Loading Docks Residential development N14 Common Area Catch Basin
Inspection
N15 Street Sweeping Private Streets
and Parking Lots
N16 Retail Gasoline Outlets Residential development

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IV.3.9 Structural Source Control BMPs
Structural Source Control BMPs
Identifier Name
Check One
If not applicable, state
brief reason Included Not
Applicable
S1 Provide storm drain system
stenciling and signage
S2
Design and construct outdoor
material storage areas to
reduce pollution introduction
No proposed outdoor
storage areas
S3
Design and construct trash
and waste storage areas to
reduce pollution introduction
No proposed trash
enclosures
S4
Use efficient irrigation systems
& landscape design, water
conservation, smart
controllers, and source control

S5
Protect slopes and channels
and provide energy
dissipation
No proposed slopes/
channels to be protected
Incorporate requirements
applicable to individual
priority project categories
(from SDRWQCB NPDES
Permit)
n/a
S6 Dock areas No proposed dock areas
S7 Maintenance bays
No proposed
maintenance bays
S8 Vehicle wash areas
No proposed vehicle
wash areas
S9 Outdoor processing areas
No proposed outdoor
processing areas
S10 Equipment wash areas
No proposed equipment
wash areas

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S11 Fueling areas
No proposed fueling
areas
S12 Hillside landscaping
No proposed hillside
landscaping
S13 Wash water control for food
preparation areas
No proposed wash water
for food processing areas
S14 Community car wash racks
No proposed community
car wash racks
S1 (CASQA Fact Sheet SD-13): Storm Drain Stenciling & Signage HOA to inspect, repair and/ or replace storm drain stenciling and signage immediately.

Inspection of stenciling and signage shall occur at least once per month and prior to the start of the raining season. Storm Drain stenciling and signage with a reference that indicates “Drains to Ocean” per CASQA BMP SD-13 Fact Sheet is required.

S4 (CASQA Fact Sheet SD-12): Use Efficient Irrigation Systems & Landscape Design HOA shall implement the timing and application methods of irrigation water to minimize the runoff of excess irrigation water into the storm drain systems. HOA to implement the following methods to reduce excessive irrigation water runoff, where applicable:
• Employ rain shutoff devices to prevent irrigation after precipitation • Utilizing landscape specific irrigation water requirements • Utilize flow reducers or shutoff valves triggered by pressure drop to control water loss due to broken sprinkler heads
• Implement landscaping practices per the County Water Conservation Resolution or City agency equivalent
• Group plants or landscaping with similar water consumption to promote surface infiltration Refer to CASQA BMP Fact Sheet SD-12 for additional information.

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IV.4 ALTERNATIVE COMPLIANCE PLAN (IF APPLICABLE)
IV.4.1 Water Quality Credits
Description of Proposed Project
Project Types that Qualify for Water Quality Credits (Select all that apply):

Redevelopment
projects that reduce
the overall
impervious footprint
of the project site.

Brownfield redevelopment, meaning
redevelopment, expansion, or reuse of
real property which may be
complicated by the presence or
potential presence of hazardous
substances, pollutants, or
contaminants, and which have the
potential to contribute to adverse
ground or surface WQ if not
redeveloped.

Higher density development projects
which include two distinct categories
(credits can only be taken for one
category): those with more than seven
units per acre of development (lower
credit allowance); vertical density
developments, for example, those with a
Floor to Area Ratio (FAR) of 2 or those
having more than 18 units per acre
(greater credit allowance).

Mixed use development, such as a
combination of residential,
commercial, industrial, office,
institutional, or other land uses which
incorporate design principles that can
demonstrate environmental benefits
that would not be realized through
single use projects (e.g. reduced
vehicle trip traffic with the potential to
reduce sources of water or air
pollution).

Transit-oriented developments, such
as a mixed use residential or commercial
area designed to maximize access to
public transportation; similar to above
criterion, but where the development
center is within one half mile of a mass
transit center (e.g. bus, rail, light rail, or
commuter train station). Such projects
would not be able to take credit for both
categories, but may have greater credit
assigned
Redevelopment
projects in an
established historic
district, historic
preservation area, or
similar significant
city area including
core City Center
areas (to be defined
through mapping).

Developments
with dedication of
undeveloped
portions to parks,
preservation areas
and other pervious
uses.

Developments
in a city center
area.

Developmen
ts in historic
districts or
historic
preservation
areas.

Live-work
developments, a variety
of developments designed
to support residential and
vocational needs together
– similar to criteria to
mixed use development;
would not be able to take
credit for both categories.

In-fill projects, the
conversion of empty
lots and other
underused spaces
into more
beneficially used
spaces, such as
residential or
commercial areas.

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Calculation of
Water Quality
Credits
(if applicable)
Water Quality credits will not be utilized on this development site.

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IV.4.2 Alternative Compliance Plan Information
n/a

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Section V Inspection/Maintenance Responsibility for BMPs The property is currently owned by City Ventures Homebuilding, LLC. The Owner will be responsible for the long-term maintenance of the project’s storm water facilities and conformance to this WQMP after construction is complete.

The owner will appoint a Homeowner’s Association (HOA) to provide long term BMP maintenance for the proposed development upon completion of construction.

Owner/ Developer:

City Ventures Homebuilding
3121 Michelson Drive, Suite 150
Irvine, Ca 92612
(949) 258-7540
Homeowner’s Association
To be determined
The owner is aware of the maintenance responsibilities of the proposed BMPs. A funding mechanism is in place to maintain the BMPs at the frequency stated in the WQMP.

CC&R review/ approval to be provided during final engineering.

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BMP Inspection/Maintenance
BMP
Reponsible
Party(s)
Inspection/
Maintenance
Activities Required
Minimum
Frequency of
Activities
Education for
Property Owners,
Tenants, Occupants &
Employees
City Ventures
Homebuilding
(Owner)/ HOA
HOA to provide education
material, a copy of the
approved WQMP and
Operation & Maintenance
Plan (O&M) to new property
owners, tenants, occupants
& employees.

At time of hiring,
leasing and/ or home
purchase.

Activity
Restrictions
City Ventures
Homebuilding
(Owner)/ HOA
HOA employees notified of
activities that are prohibited
by homeowners.

Restrictions identified
in Employee Manual
and reviewed yearly by
employees.

Common Area
Landscape
Management
City Ventures
Homebuilding
(Owner)/ HOA
HOA to hire professional
landscape company to
conduct maintenance of
landscaping to meet current
water efficiency and keep
plants healthy and bio areas
maintained with proper soil
amendments.

Regular maintenance
once a week and
monthly inspection to
determine deficiencies.

BMP Maintenance
City Ventures
Homebuilding
(Owner)/ HOA
HOA to hire professional
BMP maintenance company
to conduct regular
inspections, repairs, and
cleanings per manufacturer’s
specifications.

A minimum 2
inspections/ cleanings
per year per
manufacturer’s
specifications prior to
October 1st (before
rainy season)
Title 22 CCR
Compliance
City Ventures
Homebuilding
(Owner)/ HOA
The distribution of these
materials will be the
responsibility of the HOA at
the time of hire, lease
signing or home purchase
per property owner, tenant,
At time of hiring,
leasing and/ or home
purchase.

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Preliminary Water Quality Management Plan (WQMP)
TTM 19389

City Ventures Homebuilding, LLC Section V
CVEN-164 Preliminary WQMP Yorba Linda Page 32
or occupant or at the initial
time of hiring.

Uniform Fire Code
Implementation
City Ventures
Homebuilding
(Owner)/ HOA
HOA to comply with fire
regulations and keep
informed of the latest rules
and requirements.

Comply with annual
fire inspections and
maintain building and
access per the latest fire
codes.

Common Area
Litter Control
City Ventures
Homebuilding
(Owner)/ HOA
HOA to provide litter
removal of site parking lot
and landscape areas and to
empty communal area trash
bins.

Once per week.

Employee Training
City Ventures
Homebuilding
(Owner)/ HOA
The distribution of these
materials will be the
reasonability of the HOA at
the initial hiring of the
employee.

At time of hiring.

Private Street &
Parking Lot Sweeping
City Ventures
Homebuilding
(Owner)/ HOA
HOA to provide
maintenance of Parking Lot
and provide Street Sweeping
services.

Weekly basis.

Use efficient irrigation
systems & landscape
design, water
conservation, smart
controllers, and source
control
City Ventures
Homebuilding
(Owner)/ HOA
HOA to provide
maintenance of landscaping
to meet current water
efficiency standards and
keep plants healthily.

Regular maintenance
once a week and
monthly inspection to
determine any water
deficiencies.

Common Area Catch
Basin Inspections
City Ventures
Homebuilding
(Owner)/ HOA
HOA shall inspection
communal areas where catch
basins are located within the
surrounding area and
remove any trash/ debris.

Inspections/ Cleaning
shall occur at least
twice per month.

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Preliminary Water Quality Management Plan (WQMP)
TTM 19389

City Ventures Homebuilding, LLC Section V
CVEN-164 Preliminary WQMP Yorba Linda Page 33
Storm Drain System
Stencilling & Signage
City Ventures
Homebuilding
(Owner)/ HOA
HOA to inspect and repair
as needed all onsite storm
drain stencilling & signage.

Inspection should occur
at minimum twice per
year.

Connector Pipe Screen
(CPS) Device
City Ventures
Homebuilding
(Owner)/ HOA
HOA will be required to hire
a professional maintenance
company to provide regular
inspection, repairs, and
cleaning per manufacturer’s
specifications. All trash/
debris and loose sediment/
silt shall be removed and
screen replacement per
manufacturer’s
specifications.

Inspections/ cleanings
should occur at least
two times per year and
before the start of the
rainy season (October
1 st). Refer to
Attachment C for
additional information
and manufacturer’s
specifications.

BIO-7: Modular
Wetlands System
(MWS) Biofiltration
Vaults
City Ventures
Homebuilding
(Owner)/ HOA
Owner/ HOA will be
required to hire a
professional maintenance
company to provide
regular inspections, repairs
and cleaning per
manufacturer’s
specifications.

Inspections/
Cleanings should
occur at least two
times per year and
before the start of the
rainy season (October
1 st). Refer to
Attachment C for
additional information
and manufacturer’s
specifications.

Storm Water Sump
Pump

City Ventures
Homebuilding
(Owner)/ HOA
Owner/ HOA to conduct
regular inspections and
cleanings of pump station
area, report performance
deficiencies, and schedule
regular inspections by
professional technician.

Inspections/ cleanings
should occur at least
two times per year
and before the start of
the rainy season
(October 1st).

Scheduled
inspections by
technician should
occur at least once per
year/ per
manufacturer’s
recommendation.

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Preliminary Water Quality Management Plan (WQMP)
TTM 19389

City Ventures Homebuilding LLC Section VI
CVEN-164 Preliminary WQMP Yorba Linda Page 34
Section VI Site Plan and Drainage Plan
VI.1 SITE PLAN AND DRAINAGE PLAN
Include a site plan and drainage plan sheet set containing the following minimum information:
• Project location
• Site boundary
• Land uses and land covers, as applicable
• Suitability/feasibility constraints
• Structural BMP locations
• Drainage delineations and flow information
• Drainage connections
• BMP details
VI.2 ELECTRONIC DATA SUBMITTAL
The minimum requirement is to provide submittal of PDF exhibits in addition to hard copies.

Format must not require specialized software to open.

If the local jurisdiction requires specialized electronic document formats (CAD, GIS) to be submitted, this section will be used to describe the contents (e.g., layering, nomenclature, georeferencing, etc.) of these documents so that they may be interpreted efficiently and accurately.

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Preliminary Water Quality Management Plan (WQMP)
TTM 19389

City Ventures Homebuilding LLC Section VII
CVEN 164 Preliminary WQMP Yorba Linda Page 35
Section VII Educational Materials
Refer to the Orange County Stormwater Program (www.ocwatersheds.com) for a library of materials available.

Education Materials
Residential Material
(http://www.ocwatersheds.com)
Check If
Applicable
Business Material
(http://www.ocwatersheds.com)
Check If
Applicable
The Ocean Begins at Your Front Door Tips for the Automotive Industry Tips for Car Wash Fund-raisers Tips for Using Concrete and Mortar Tips for the Home Mechanic Tips for the Food Service Industry Homeowners Guide for Sustainable
Water Use
Proper Maintenance Practices for Your
Business
Household Tips
Other Material
Check If
Attached Proper Disposal of Household
Hazardous Waste
Recycle at Your Local Used Oil
Collection Center (North County)
Recycle at Your Local Used Oil
Collection Center (Central County)
Recycle at Your Local Used Oil
Collection Center (South County)
Tips for Maintaining a Septic Tank
System
Responsible Pest Control
Sewer Spill
Tips for the Home Improvement Projects
Tips for Horse Care
Tips for Landscaping and Gardening
Tips for Pet Care
Tips for Pool Maintenance
Tips for Residential Pool, Landscape and
Hardscape Drains
Tips for Projects Using Paint

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Attachment A : Preliminary WQMP Exhibit

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AHEADAHEADAHEAD

SIGNALSIGNALSIGNAL

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Attachment B : Technical Guidance Figures & Worksheets

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ORANGE COUNTY RIVERSIDE COUNTY

ORANGE COUNTY SAN BERNARDINO COUNTY

ORANGE COUNTY

LOS ANGELES COUNTY

ORANGE COUNTY ORANGE COUNTY LOS ANGELES COUNTY LOS ANGELES COUNTY

1.05 0.7

0.95 1

0.9 0.85

0.8 0.75

0.7 0.65

0.95 0.7

0.9 0.9

0.75 P:\9526E\6-GIS\Mxds\Reports\InfiltrationFeasability_20110215\9526E_FigureXVI-1_RainfallZones_20110215.mxd FIGURE JOB TITLE SCALE 1" = 1.8 miles DESIGNED

DRAWINGCHECKED
BMP
04/22/10
DATEJOB NO.

THTH9526-E

ORANGE COUNTY

TECHNICAL GUIDANCE

DOCUMENT
ORANGE CO. CA

RAINFALL ZONES
SUBJECT TO FURTHER REVISION 0 1.8 3.6 7.2
Miles
036 12
Kilometers
LEGEND
Orange County Precipitation Stations
24 Hour, 85th Percentile Rainfall (Inches)
24 Hour, 85th Percentile Rainfall (Inches) - Extrapolated City Boundaries
Rainfall Zones
Design Capture Storm Depth (inches)

0.65"

0.7 0.75

0.80 0.85

0.90 0.95

1.00 1.10"
Note: Events defined as 24-hour periods (calendar days) with greater than 0.1 inches of rainfall.

For areas outside of available data coverage, professional judgment shall be applied.

XVI-1

PROJECT SITE

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P:\9526E\6-GIS\Mxds\SuceptabilityMaps_20100505\9526E_SantaAnaRiverSusceptibility_20100430.mxd Cleveland
National Forest
San Bernardino
County
Riverside County
South Orange
County
Newport Bay
Watershed
Stabilized by
Grade Control
Structure
San Gabriel-Coyote Creek
Watershed
Anaheim BayHuntington Harbor
Watershed
Peters
Canyon
Reservoir
Olive
Hills
Kraemer
Basin
Carbon
Canyon
Walnut
Canyon
Reservoir
Irvine
Lake
Anaheim
Lake
Warner
Basin
Miller
Retarding
Basin
Bartlett
Retarding
Basin
Fletcher
Retarding
Basin

SOUTHPARK
PUMP

STATION
Villa
Park Dam
Yorba Linda
Reservoir
Sources: Esri, DeLorme, NAVTEQ, USGS, Intermap, iPC, NRCAN, Esri Japan, METI, Esri China (Hong Kong), Esri (Thailand), TomTom, 2012 FIGURE
3 JOB TITLE SCALE 1" = 12000'

DESIGNEDDRAWINGCHECKED
BMP
04/30/10
DATEJOB NO.

THTH9526-E

ORANGE COUNTY

WATERSHED

MASTER PLANNING
ORANGE CO. CA

SUSCEPTIBILITY ANALYIS

SANTA ANA RIVER
I! 0 12,000 24,000
Feet
Susceptibility
Potential Areas of Erosion, Habitat, &
Physical Structure Susceptibility
Channel Type
Earth (Unstable)
Earth (Stabilized)
Stabilized
Tidel Influence
<= Mean High Water Line (4.28')
Water Body
Basin
Dam
Lake
Reservoir
Forest Areas
Cleveland National Forest
Federal Lands
Amarus Salt Marsh
Sources: Esri, DeLorme, NAVTEQ,
USGS, Intermap, iPC, NRCAN, Esri
Japan, METI, Esri China (Hong
Kong), Esri (Thailand), TomTom,
2012
SUSCEPTIBILITY MAP UPATE (FEB 2013)
Project Location

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ORANGE COUNTY RIVERSIDE COUNTY

ORANGE COUNTY SAN BERNARDINO COUNTY

ORANGE COUNTY

LOS ANGELES COUNTY

ORANGE COUNTY ORANGE COUNTY LOS ANGELES COUNTY LOS ANGELES COUNTY P:\9526E\6-GIS\Mxds\Reports\InfiltrationFeasability_20110215\9526E_FigureXVI-2f_NorthOCGroundwaterProtectionAreasStreetMap_20110215.mxd FIGURE
XVI-2f JOB TITLE SCALE 1" = 1.25 miles DESIGNED DRAWING CHECKED BMP 04/22/10 DATE JOB NO. THTH 9526-E

ORANGE COUNTY

INFILTRATION STUDY
ORANGE CO. CA

NORTH ORANGE COUNTY

GROUNDWATER PROTECTION
AREAS

SUBJECT TO FURTHER REVISION
Note: Individual contamination sites are not plotted.

See State Water Resources Control Board Geotracker database (http://geotracker.waterboards.ca.gov),
Department of Toxic Substance Control Envirostor database (http://www.envirostor.dtsc.ca.gov) and other applicable sources for current listing of active contaminated sites.

Groundwater basin and plume protection boundaries for
South Orange County are not shown on this exhibit
at this time
I!
0 1.25 2.55
Miles
0248
Kilometers
LEGEND
City Boundaries
OCWD Groundwater Basin Protection Boundary
Plume Protection Boundaries
North Basin Groundwater Protection Project
South Basin Groundwater Protection Project
El Toro Marine Base
Tustin Marine Air Base
Approximate Selenium Contamination Area

PROJECT SITE

Page 1465 of 2028 ends

ORANGE COUNTY RIVERSIDE COUNTY

ORANGE COUNTY SAN BERNARDINO COUNTY

ORANGE COUNTY

LOS ANGELES COUNTY

ORANGE COUNTY ORANGE COUNTY LOS ANGELES COUNTY LOS ANGELES COUNTY 10 10
3 5
10 30
10 30
10 20
10 10
5 50
3 30
30 30 30 20
5 10
20 30
50 10
30 20
P:\9526E\6-GIS\Mxds\Reports\InfiltrationFeasability_20110215\9526E_FigureXVI-2d_DepthToGroundwaterOverview_20110215.mxd FIGURE
XVI-2d JOB TITLE SCALE 1" = 1.25 miles DESIGNED DRAWING CHECKED BMP 02/09/11 DATE JOB NO. THTH 9526-E

ORANGE COUNTY

INFILTRATION STUDY
ORANGE CO. CA

NORTH ORANGE COUNTY

MAPPED DEPTH TO FIRST

GROUNDWATER

SUBJECT TO FURTHER REVISION
Note: Data are not available for South Orange County at this time.

Source:

Sprotte, Fuller and Greenwood, 1980.

California Division of Mines and Geology;
California Geological Survey
I!
0 1.25 2.55
Miles
0248
Kilometers
LEGEND
Depth To First Groundwater Contours
City Boundaries
OCWD Groundwater Basin Protection Boundary

PROJECT SITE
(Refer to project-specific
geotechnical report for
groundwater levels)

Page 1466 of 2028 ends

ORANGE COUNTY RIVERSIDE COUNTY

ORANGE COUNTY SAN BERNARDINO COUNTY

ORANGE COUNTY

LOS ANGELES COUNTY

ORANGE COUNTY ORANGE COUNTY LOS ANGELES COUNTY LOS ANGELES COUNTY P:\9526E\6-GIS\Mxds\Reports\InfiltrationFeasability_20110215\9526E_FigureXVI-2a_HydroSoils_20110215.mxd FIGURE
XVI-2a JOB TITLE SCALE 1" = 1.8 miles DESIGNED DRAWING CHECKED BMP 02/09/11 DATE JOB NO. THTH9526-E ORANGE COUNTY INFILTRATION STUDY ORANGE CO. CA NRCS HYDROLOGIC SOILS GROUPS

SUBJECT TO FURTHER REVISION
Source:

Soils: Natural Resources Conservation Service (NRCS)
Soil Survey - soil_ca678, Orange County & Western Riverside Date of publication: 2006-02-08
I!
0 1.8 3.6 7.2
Miles
0 2.55 10
Kilometers
LEGEND
City Boundaries
Hydrologic Soil Groups
A Soils
B Soils
C Soils
D Soils
http://websoilsurvey.nrcs.usda.gov/app/HomePage.htm

PROJECT SITE

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DMA A1
Worksheet B: Simple Design Capture Volume Sizing Method Step 1: Determine the design capture storm depth used for calculating volume 1 Enter design capture storm depth from Figure III.1, d (inches) d= 0.9 inches 2 Enter the effect of provided HSCs, dHSC (inches)
(Worksheet A) dHSC= 0 inches
3 Calculate the remainder of the design capture storm depth, dremainder (inches) (Line 1 – Line 2) dremainder= 0.9 inches Step 2: Calculate the DCV
1 Enter Project area tributary to BMP (s), A (acres) A= 1.90 acres 2 Enter Project Imperviousness, imp (unitless) imp= 1.00 3 Calculate runoff coefficient, C= (0.75 x imp) + 0.15 C= 0.90 4 Calculate runoff volume, Vdesign= (C x dremainder x A x 43560 x (1/12)) Vdesign= 5,586.57 cu-ft
Step 3: Design BMPs to ensure full retention of the DCV Step 3a: Determine design infiltration rate N/A
1 Enter measured infiltration rate, Kmeasured (in/hr)
(Appendix VII) Kmeasured= NA In/hr
2 Enter combined safety factor from Worksheet H, Sfinal (unitless) Sfinal= NA
3 Calculate design infiltration rate, Kdesign = Kmeasured / Sfinal Kdesign= NA In/hr
Step 3b: Determine minimum BMP footprint
4 Enter drawdown time, T (max 48 hours) T= NA Hours
5 Calculate max retention depth that can be drawn down within the drawdown time (feet), Dmax = Kdesign x T x (1/12) Dmax= NA feet 6 Calculate minimum area required for BMP (sq-ft), Amin = Vdesign/ dmax
Amin= NA sq-ft

Page 1468 of 2028 ends

Worksheets from Orange County Technical Guidance Document (5-19-2011) See TGD for instructions and/or examples related to these worksheets www.ocwatersheds.com/WQMP.aspx
DMA A2
Worksheet B: Simple Design Capture Volume Sizing Method Step 1: Determine the design capture storm depth used for calculating volume 1 Enter design capture storm depth from Figure III.1, d (inches) d= 0.9 inches 2 Enter the effect of provided HSCs, dHSC (inches)
(Worksheet A) dHSC= 0 inches
3 Calculate the remainder of the design capture storm depth, dremainder (inches) (Line 1 – Line 2) dremainder= 0.9 inches Step 2: Calculate the DCV
1 Enter Project area tributary to BMP (s), A (acres) A= 0.74 acres 2 Enter Project Imperviousness, imp (unitless) imp= 1.00 3 Calculate runoff coefficient, C= (0.75 x imp) + 0.15 C= 0.90 4 Calculate runoff volume, Vdesign= (C x dremainder x A x 43560 x (1/12)) Vdesign= 2,175.8 cu-ft
Step 3: Design BMPs to ensure full retention of the DCV Step 3a: Determine design infiltration rate N/A
1 Enter measured infiltration rate, Kmeasured (in/hr)
(Appendix VII) Kmeasured= NA In/hr
2 Enter combined safety factor from Worksheet H, Sfinal (unitless) Sfinal= NA
3 Calculate design infiltration rate, Kdesign = Kmeasured / Sfinal Kdesign= NA In/hr
Step 3b: Determine minimum BMP footprint
4 Enter drawdown time, T (max 48 hours) T= NA Hours
5 Calculate max retention depth that can be drawn down within the drawdown time (feet), Dmax = Kdesign x T x (1/12) Dmax= NA feet 6 Calculate minimum area required for BMP (sq-ft), Amin = Vdesign/ dmax
Amin= NA sq-ft

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DMA A1
Worksheet D: Capture Efficiency Method for Flow-Based BMPs Step 1: Determine the design capture storm depth used for calculating volume 1 Enter the time of concentration, Tc (min) (See Appendix IV.2) Tc= 5.00 2 Using Figure III.4, determine the design intensity at which the estimated time of concentration (Tc) achieves 80% capture efficiency, I1
I1= 0.26 in/hr
3 Enter the effect depth of provided HSCs upstream, dHSC (inches) (Worksheet A) dHSC= 0 inches
4 Enter capture efficiency corresponding to dHSC, Y2
(Worksheet A) Y2= 0 %
5 Using Figure III.4, determine the design intensity at which the time of concentration (Tc) achieves the upstream capture efficiency(Y2), I2
I2= 0 in/hr
6 Determine the design intensity that must be provided by BMP, Idesign= I1-I2
Idesign= 0.26 in/hr
Step 2: Calculate the design flowrate
1 Enter Project area tributary to BMP (s), A (acres) A= 1.90 acres 2 Enter Project Imperviousness, imp (unitless) imp= 1.00 * 3 Calculate runoff coefficient, C= (0.75 x imp) + 0.15 C= 0.90 4 Calculate design flowrate, Qdesign= (C x idesign x A) Qdesign= 0.445 cfs Supporting Calculations
Describe system:

Surface runoff will be conveyed through the private street to proposed curb inlet catch basins equipped with a Dvert System that diverts flows to proposed Biofiltration Vault for water quality treatment. *Assumed 100% impervious coverage utilized for preliminary calculations. Actual impervious coverage will be calculated in final engineering.

Provide time of concentration assumptions:

The time of concentration was assumed to be 5 minutes for conservative purposes.

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Worksheets from Orange County Technical Guidance Document (5-19-2011) See TGD for instructions and/or examples related to these worksheets www.ocwatersheds.com/WQMP.aspx
DMA A2
Worksheet D: Capture Efficiency Method for Flow-Based BMPs Step 1: Determine the design capture storm depth used for calculating volume 1 Enter the time of concentration, Tc (min) (See Appendix IV.2) Tc= 5.00 2 Using Figure III.4, determine the design intensity at which the estimated time of concentration (Tc) achieves 80% capture efficiency, I1
I1= 0.26 in/hr
3 Enter the effect depth of provided HSCs upstream, dHSC (inches) (Worksheet A) dHSC= 0 inches
4 Enter capture efficiency corresponding to dHSC, Y2
(Worksheet A) Y2= 0 %
5 Using Figure III.4, determine the design intensity at which the time of concentration (Tc) achieves the upstream capture efficiency(Y2), I2
I2= 0 in/hr
6 Determine the design intensity that must be provided by BMP, Idesign= I1-I2
Idesign= 0.26 in/hr
Step 2: Calculate the design flowrate
1 Enter Project area tributary to BMP (s), A (acres) A= 0.74 acres 2 Enter Project Imperviousness, imp (unitless) imp= 1.00 * 3 Calculate runoff coefficient, C= (0.75 x imp) + 0.15 C= 0.90 4 Calculate design flowrate, Qdesign= (C x idesign x A) Qdesign= 0.173 cfs Supporting Calculations
Describe system:

Provide time of concentration assumptions:

The time of concentration was assumed to be 5 minutes for conservative purposes.

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Worksheets from Orange County Technical Guidance Document (5-19-2011) See TGD for instructions and/or examples related to these worksheets www.ocwatersheds.com/WQMP.aspx
Worksheet D: Capture Efficiency Method for Flow-Based BMPs Graphical Operations
Provide supporting graphical operations. See Example III.7.

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Worksheet H: Factor of Safety and Design Infiltration Rate Worksheet DMA A1 and A2
Factor Category Factor Description
Assigned
Weight (w)
Factor
Value (v)
Product (p)
p = w x v
A Suitability
Assessment
Soil assessment methods 0.25 1 0.25
Predominant soil texture 0.25 1 0.25
Site soil variability 0.25 1 0.25
Depth to groundwater /
impervious layer 0.25 2 0.50
Suitability Assessment Safety Factor, SA = Σp 1.25
B Design
Tributary area size 0.25 2 0.50
Level of pretreatment/ expected
sediment loads 0.25 1 0.25
Redundancy 0.25 2 0.50
Compaction during construction 0.25 1 0.25
Design Safety Factor, SB = Σp 1.5
Combined Safety Factor, STOT= SA x SB 1.875  use 2
Measured Infiltration Rate, inch/hr, KM
(corrected for test-specific bias) 0.1 inches/ hr
Design Infiltration Rate, in/hr, KDESIGN = KM / STOT 0.05 inches/ hr Supporting Data
Percolation testing was conducted by Alta Geotechnical as follows:

SUMMARY OF RESULTS
Boring Measured Infiltration Rate (inches per hour)
P-1 0.8
P-2 0.1
Refer to Attachment E of this Preliminary WQMP for the Geotechnical Investigation, Dated January 2025.

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Worksheet I: Summary of Groundwater-related Feasibility Criteria 1 Is project large or small? (as defined by Table VIII.2) circle one
Large Small
2 What is the tributary area to the BMP? A 2.647 acres
3 What type of BMP is proposed? Biofiltration
4 What is the infiltrating surface area of the proposed BMP? ABMP 0 sq-ft 5 What land use activities are present in the tributary area (list all) Multi-Family Residential
6 What land use-based risk category is applicable? L M H 7 If M or H, what pretreatment and source isolation BMPs have been considered and are proposed (describe all):

Proposed MWS System Biofiltration Vaults will provide treatment for the required design flow rate. 8 What minimum separation to mounded seasonally high
groundwater applies to the proposed BMP?
See Section VIII.2 (circle one)
5 ft 10 ft
9 Provide rationale for selection of applicable minimum separation to seasonally high mounded groundwater:

Per the TGD Section VIII.2, the following applies to a subsurface infiltration gallery:
“Separation to mounded seasonally high groundwater shall be at least 10 feet for infiltration devices that inject water below the subsurface and surface infiltration BMPs with tributary area and land use activities that are considered to pose a more significant risk to groundwater quality.”
10 What is separation from the infiltrating surface to seasonally high groundwater? SHGWT 5 ft
11 What is separation from the infiltrating surface to mounded seasonally high groundwater?
Mounded
SHGWT n/a ft
12 Describe assumptions and methods used for mounding analysis:
13 Is the site within a plume protection boundary (See Figure Y N N/A

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Worksheets from Orange County Technical Guidance Document (5-19-2011) See TGD for instructions and/or examples related to these worksheets www.ocwatersheds.com/WQMP.aspx
Worksheet I: Summary of Groundwater-related Feasibility Criteria VIII.2)?
14 Is the site within a selenium source area or other natural plume area (See Figure VIII.2)? Y N N/A
15 Is the site within 250 feet of a contaminated site? Y N N/A 16 If site-specific study has been prepared, provide citation and briefly summarize relevant findings:
n/a
17 Is the site within 100 feet of a water supply well, spring, septic system? Y N N/A
18 Is infiltration feasible on the site relative to groundwaterrelated criteria? Y N Provide rationale for feasibility determination:

Infiltration testing resulted in low rates, therefore infiltration is infeasible for this site.

Note: if a single criterion or group of criteria would render infiltration infeasible, it is not necessary to evaluate every question in this worksheet.

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Worksheet J: Summary of Harvested Water Demand and Feasibility Entire Site 1 What demands for harvested water exist in the tributary area (check all that apply):
2 Toilet and urinal flushing □
3 Landscape irrigation 
4 Other:_______________________________________________________ □ 5 What is the design capture storm depth? (Figure III.1) d 0.90 inches 6 What is the project size? A 2.647 ac
7 What is the acreage of impervious area? * IA 2.25 ac
For projects with multiple types of demand (toilet flushing, irrigation demand, and/or other demand) 8 What is the minimum use required for partial capture? (Table X.6) gpd
9 What is the project estimated wet season total daily use (Section X.2)? gpd
10 Is partial capture potentially feasible? (Line 9 > Line 8?) For projects with only toilet flushing demand
11 What is the minimum TUTIA for partial capture? (Table X.7) 12 What is the project estimated TUTIA?
13 Is partial capture potentially feasible? (Line 12 > Line 11?) For projects with only irrigation demand
14 What is the minimum irrigation area required based on conservation landscape design? (Table X.8) [1.59x1.01] 2.27 ac 15 What is the proposed project irrigated area? (multiply conservation landscaping by 1; multiply active turf by 2) 0.397 ac 16 Is partial capture potentially feasible? (Line 15 > Line 14?) No Provide supporting assumptions and citations for controlling demand calculation:

Due to the proposed development type, density and amount of available landscaping, Harvest and Use BMPs for irrigation purposes will not be feasible.
* For preliminary purposes, an assumed 85% impervious coverage based on development type was utilized for these calculations.

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Attachment C : Site BMPs

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Page 1478 of 2028 ends

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Stormwater Connector Pipe Screen Page 1 of 4
Section [________]
Stormwater Connector Pipe Screen
PART 1 – GENERAL

01.01.00 Purpose
The purpose of this specification is to establish generally acceptable criteria for Connector Pipe Screens used for collecting trash and debris inside catch basins. It is intended to serve as a guide to producers, distributors, architects, engineers, contractors, plumbers, installers, inspectors, agencies and users; to promote understanding regarding materials, manufacture and installation; and to provide for identification of devices complying with this specification.

01.02.00 Description
Stormwater Connector Pipe Screens (CPS) are used to prevent trash and debris from entering the stormwater system during dry weather and moderate storm flows by keeping the trash inside the catch basin. The CPS is a screen placed permanently or temporarily in a catch basin at the location of the outlet pipe. The screen separates trash and debris from stormwater treatment flows. Flows that exceed the treatment flow rate bypass over the top of the screen. When the outlet pipe is located below a curb opening the CPS features a lid to prevent debris from passing behind the screen and flowing directly to the outlet pipe. The CPS shall be designed to retain all trash larger than 5 mm (0.197 inches) in the catch basin.

01.03.00 Manufacturer
The manufacturer of the CPS shall be one that is regularly engaged in the engineering, design and production of systems developed for the treatment of stormwater runoff for at least (10) years, and which has a history of successful production, acceptable to the engineer of work. In accordance with the drawings, the CPS(s) shall be a screen device manufactured/distributed by Bio Clean Environmental Services, Inc., or assigned distributors or licensees. Bio Clean Environmental Services, Inc. can be reached at:
5796 Armada Drive, Suite 250
Carlsbad, CA 92008
Phone: (760) 433-7640
Fax: (760) 433-3176
www.biocleanenvironmental.net

01.04.00 Submittals

01.04.01 Submittal drawings will be provided with each order to the contractor and engineer of work.

01.04.02 Submittal drawings are to detail the CPS, its components and the sequence for installation, including:
• CPS configuration with primary dimensions
• Various CPS components
• Any accessory equipment

01.04.03 Inspection and maintenance documentation submitted upon request.

01.05.00 Work Included

01.05.01 Specification requirements for installation of CPS.

01.05.02 Manufacturer to supply CPS(s):

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Stormwater Connector Pipe Screen Page 2 of 4
• Screen
• Mounting hardware
• Bypass lid with supports (when required)
PART 2 – COMPONENTS

02.01.01 The CPS shall have a sufficient structural integrity to withstand a lateral force of standing water within the catch basin area when the screen becomes 100% clogged. The CPS unit shall be bolted to the catch basin walls.

02.01.02 The CPS shall be configured with deflector plates or screens preventing trash from falling between the screen and connector pipe. The deflector plate shall be designed to withstand a vertical load.

02.01.03 The gap at the bottom, sides, and joints of the CPS unit shall not exceed 5 mm (0.197 inches).

02.01.04 The CPS shall include vertical structural stiffeners extending the full length of the screen in the form as bends in the screen itself, a bolting surface to fasten the CPS to the wall of the catch basin, and support for the upper portion of the CPS unit referred to as the “bypass.”

02.01.05 All parts/components of the CPS unit must be sized to fit through the catch basin’s manhole opening.

02.01.06 The CPS frame shall be fabricated from 304 stainless steel.

02.01.07 The CPS screen shall be fabricated from perforated 304 stainless steel. The screen shall have a minimum thickness of 16 gauge. The geometrical opening shape shall have a diameter of 5 mm (0.197 inches).

02.01.08 The screen material used shall have at least 45% open area.

02.01.09 Any edge of the CPS that is not flush with the wall or floor of the catch basin shall be smooth with no prongs or jagged edges.

02.01.10 The assembly bolts, screws, nuts, and washers shall be fabricated entirely from 316 stainless steel. The concrete anchor bolts shall use a wedge anchor, with Type 316 stainless steel threaded rods, nuts, and washers.

PART 3 – PERFORMANCE

03.01.00 General

03.01.01 Function - The CPS has no moving internal components and functions based on gravity flow, unless otherwise specified. Stormwater runoff enters the catch basin through a curb opening and flows toward the connector pipe. The CPS is placed to intercept flows prior to exiting the catch basin through the connector pipe. The CPS must be able to be removed through the catch basin opening. Stormwater flow up to the peak treatment rate is processed through the screen. Flows in excess of the peak treatment rate will overtop the screen in a bypass. The lid (when required) shall be place high enough above the screen to allow for full bypass flow.

03.01.02 Pollutants - The CPS will remove and retain trash and debris larger than 5 mm in diameter entering the catch basin during frequent storm events and specified flow rates.

03.01.03 Treatment Flow Rate - The CPS operates through gravity flow. The CPS is to be sized so the screen is capable of passing the calculated project specific water quality flow rate per local standards. All treatment flow rates must include a 50% screen clogging factor.

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Stormwater Connector Pipe Screen Page 3 of 4

03.01.04 Bypass Flow Rate – The CPS is designed to fit within the catch basin in a way not to affect the existing hydraulics and treat or bypass all flows. The bypass must be sized with a surface area greater than the outlet pipe size, thus the CPS shall not be a critical point of flow restriction.

PART 4 - EXECUTION

04.01.00 General
The installation and use of the CPS shall conform to all applicable national, state, municipal and local specifications.

04.02.00 Installation
The contractor shall furnish all labor, equipment, materials and incidentals required to install the CPS device(s) and appurtenances in accordance with the drawings, installation manual, and these specifications, and be inspected and approved by the local governing agency. Any damage to catch basin and surrounding infrastructure caused by the installation of the CPS is the responsibility of the installation contractor.

04.02.01 CPS and all components or accessories shall be inserted through the catch basin and properly secured per manufactures installation manual and these specifications.

04.03.00 Shipping, Storage and Handling

04.03.01 Shipping – CPS shall be shipped to the contractor’s address and is the responsibility of the contractor to transport the unit(s) to the exact site of installation.

04.03.02 Storage and Handling– The contractor shall exercise care in the storage and handling of the CPS(s) and its components prior to and during installation.

Any repair or replacement costs associated with events occurring after delivery is accepted, and unloading has commenced shall be born by the contractor. The CPS(s) and its components shall always be stored indoors and transported inside the original shipping container(s) until the CPS(s) are ready to be installed. The CPS shall always be handled with care and lifted according to OSHA and NIOSA lifting recommendations and/or contractor’s workplace safety professional recommendations.

04.04.00 Maintenance and Inspection

04.04.01 Inspection – After installation, the contractor shall demonstrate that the CPS has been properly installed at the correct location(s), elevations, and with appropriate supports and fasteners. All components associated with the CPS and its installation shall be subject to inspection by the engineer of work, governing agency, and the manufacture at the place of installation. In addition, the contractor shall demonstrate that the CPS has been installed per the manufacturer’s specifications and recommendations. CPS(s) shall be physically inspected regularly in accordance to owner’s Stormwater Pollution Prevention Plans (SWPPP) and manufacture’s recommendations. An inspection record shall be kept by the inspection operator. The record shall include the condition of the CPS and its appurtenances. The most current copy of the inspection record shall always be copied and placed in the owner’s SWPPP.

04.04.02 Maintenance – The maintenance shall be performed by someone qualified. A Maintenance Manual is available upon request from the manufacturer. The

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Stormwater Connector Pipe Screen Page 4 of 4
manual has detailed information regarding the maintenance of the CPS(s). A detailed Maintenance Record shall be kept by the maintenance operator. The Maintenance Record shall include any maintenance activities preformed, amount and description of debris collected, and the condition of the CPS. The most current copy of the Maintenance Record shall always be copied and placed in the owner’s Stormwater Pollution Prevention Plan (SWPPP) per governing agency. Upon cleaning: no trash or debris shall be located in the catch basin, on top of the bypass lid, or between the screen; no vegetation shall block the catch basin opening or connector pipe; and no trash or debris shall be located within the catch basin opening.

04.04.03 Material Disposal - All debris, trash, organics, and sediments captured and removed from the CPS shall be transported and disposed of at an approved facility for disposal in accordance with local and state regulations. Please refer to state and local regulations for the proper disposal of toxic and nontoxic material.

PART 5 – QUALITY ASSURANCE

05.01.00 Warranty
The manufacturer shall guarantee the CPS against all manufacturing defects in materials and workmanship for a period of (3) years from the date of delivery to the contractor. The manufacturer shall be notified of repair or replacement issues in writing within the warranty period. The CPS is limited to recommended application for which it was designed. [End of This Section]

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GENERAL NOTES INSTALLATION NOTES

ISO VIEW - U SHAPE

TOP SECTION VIEW - U SHAPE

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INSTALLATION NOTES:

PLAN VIEW
(GRATE NOT SHOWN)

ELEVATION VIEW

FLOW DIAGRAM

GRATE INLET FILTER

FULL CAPTURE

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Street Sweeping and Vacuuming SE-7
January 2011 California Stormwater BMP Handbook 1 of 2
Construction
www.casqa.org
Description and Purpose
Street sweeping and vacuuming includes use of self-propelled and walk-behind equipment to remove sediment from streets and roadways, and to clean paved surfaces in preparation for final paving. Sweeping and vacuuming prevents sediment from the project site from entering storm drains or receiving waters.

Suitable Applications
Sweeping and vacuuming are suitable anywhere sediment is tracked from the project site onto public or private paved streets and roads, typically at points of egress. Sweeping and vacuuming are also applicable during preparation of paved surfaces for final paving.

Limitations
Sweeping and vacuuming may not be effective when sediment is wet or when tracked soil is caked (caked soil may need to be scraped loose).

Implementation
 Controlling the number of points where vehicles can leave the site will allow sweeping and vacuuming efforts to be focused, and perhaps save money.
 Inspect potential sediment tracking locations daily.
 Visible sediment tracking should be swept or vacuumed on a daily basis.

Categories
EC Erosion Control
SE Sediment Control 
TC Tracking Control 
WE Wind Erosion Control
NS Non-Stormwater
Management Control
WM Waste Management and
Materials Pollution Control
Legend:
 Primary Objective
 Secondary Objective
Targeted Constituents
Sediment 
Nutrients
Trash 
Metals
Bacteria
Oil and Grease 
Organics
Potential Alternatives
None
If User/Subscriber modifies this fact
sheet in any way, the CASQA
name/logo and footer below must be
removed from each page and not
appear on the modified version.

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Street Sweeping and Vacuuming SE-7
January 2011 California Stormwater BMP Handbook 2 of 2
Construction
www.casqa.org
 Do not use kick brooms or sweeper attachments. These tend to spread the dirt rather than remove it.
 If not mixed with debris or trash, consider incorporating the removed sediment back into the project
Costs
Rental rates for self-propelled sweepers vary depending on hopper size and duration of rental.

Expect rental rates from $58/hour (3 yd3 hopper) to $88/hour (9 yd3 hopper), plus operator costs. Hourly production rates vary with the amount of area to be swept and amount of sediment. Match the hopper size to the area and expect sediment load to minimize time spent dumping.

Inspection and Maintenance
 Inspect BMPs in accordance with General Permit requirements for the associated project type and risk level. It is recommended that at a minimum, BMPs be inspected weekly, prior to forecasted rain events, daily during extended rain events, and after the conclusion of rain events.
 When actively in use, points of ingress and egress must be inspected daily.  When tracked or spilled sediment is observed outside the construction limits, it must be removed at least daily. More frequent removal, even continuous removal, may be required in some jurisdictions.
 Be careful not to sweep up any unknown substance or any object that may be potentially hazardous.
 Adjust brooms frequently; maximize efficiency of sweeping operations.  After sweeping is finished, properly dispose of sweeper wastes at an approved dumpsite.

References
Stormwater Quality Handbooks - Construction Site Best Management Practices (BMPs) Manual, State of California Department of Transportation (Caltrans), November 2000.

Labor Surcharge and Equipment Rental Rates, State of California Department of Transportation (Caltrans), April 1, 2002 – March 31, 2003.

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Attachment D : O&M Plan

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Operations and Maintenance (O&M) Plan
Water Quality Management Plan
For
Tract 19389
Yorba Linda, CA
APN: 323-081-35
Legal Description:

THE LAND REFERRED TO HEREIN BELOW IS SITUATED IN THE CITY OF YORBA LINDA IN THE COUNTY OF ORANGE, STATE OF CALIFORNIA, AND IS DESCRIBED AS FOLLOWS:

PARCEL A:

PARCEL B:

THAT PORTION OF LOT 8 IN BLOCK 9 OF THE YORBA LINDA TRACT, IN THE CITY OF YORBA LINDA, COUNTY OF ORANGE, STATE OF CALIFORNIA, AS SHOWN ON A MAP THEREOF RECORDED IN BOOK 5, PAGES 17 AND 18, OF MISCELLANEOUS MAPS, IN THE OFFICE OF THE COUNTY RECORDER OF SAID COUNTY DESCRIBED AS FOLLOWS: BEGINNING AT A POINT IN THE EAST LINE OF SAID LOT 8, DISTANT THEREON 158.80 FEET SOUTHERLY FROM THE NORTHEAST CORNER OF SAID LOT; THENCE WESTERLY PARALLEL WITH THE NORTH LINE OF SAID LOT, 264.16 FEET, MORE OR LESS, TO THE EAST LINE OF THE WEST 396 FEET OF SAID LOT, SAID DISTANCE OF 396 FEET BEING MEASURED FROM THE CENTER LINE OF OHIO STREET, 60 FEET TO WIDTH, ADJOINING SAID LOT ON THE WEST; THENCE SOUTHERLY ALONG SAID EAST LINE, 469.70 FEET, MORE OR LESS, TO THE NORTH LINE OF YORBA LINDA BOULEVARD, 60 FEET IN WIDTH, ADJOINING SAID LOT ON THE SOUTH;THENCE EASTERLY ALONG SAID NORTH LINE, 108.13 FEET, MORE OR LESS, TO THE WEST LINE OF THE EAST 156 FEET OF SAID LOT 8;THENCE NORTHERLY ALONG SAID WEST LINE, 310 FEET TO THE NORTH LINE OF THE SOUTH 340 FEET OF SAID LOT, SAID DISTANCE OF 340 FEET BEING MEASURED FROM THE CENTER LINE OF YORBA LINDA BOULEVARD;THENCE EASTERLY ALONG SAID NORTH LINE, 156 FEET TO THE EAST LINE OF SAID LOT; THENCE NORTHERLY ALONG SAID EAST LINE, 158.79 FEET, MORE OR LESS, TO THE POINT OF BEGINNING.

EXCEPT THEREFROM THAT PORTION OF SAID LAND CONVEYED TO THE CITY OF YORBA LINDA, A MUNICIPAL CORPORATION, AS SET FORTH AND DESCRIBED BY THAT CERTAIN DOCUMENT RECORDED APRIL 28, 1989 AS INSTRUMENT NO. 89-226375 OF OFFICIAL RECORDS.

APN: 323-081-35

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Attachment D, Operations and Maintenance Plan
BMP
Applicable?
Yes/ No
BMP Name and BMP Implementation, Maintenance, and
Inspection Procedures
Implementation, Maintenance, and
Inspection Frequency and Schedule
Person or Entity with
Operation and Maintenance
Responsibility
Non-Structural Source Control BMPs
Yes
N1. Education for Property Owners, Tenants, and Occupants This will be addressed through educational materials. All included materials provide ways of mitigating stormwater pollution in everyday activities associated with residents as well as employees of the property management company and their sub-contractors. Practical informational materials are provided to residents, occupants, or tenants to increase the public’s understanding of stormwater quality, sources of pollutants, and what they can do to reduce pollutants in stormwater.

HOA/ OWNER to provide educational
materials, a copy of the approved WQMP
and Operation & Maintenance Plan (O&M)
to new property owners, tenants, occupants
& employees, at time of hire, leasing and/ or
home purchase.

HOA/ OWNER
Yes
N2. Activity Restriction Rules or guidelines for developments are established within the appropriate documents which prohibit activities that can result in discharges of pollutants.

HOA/ OWNER employees notified of
activities that are prohibited by
homeowners.

Restrictions identified in
Employee Manual and
reviewed yearly by employees.

Yes
N3. Common Area Landscape Management Specific practices are followed, and ongoing maintenance is conducted to minimize erosion and over-irrigation, conserve water, and reduce pesticide and fertilizer applications.

Professional landscape company to conduct
maintenance of landscaping to meet current
water efficiency and keep plants healthy and
bio areas maintained with proper soil
amendments. Regular maintenance once a
week and monthly inspection to determine
deficiencies
The HOA/ OWNER will
maintain or hire professionals
to manage the upkeep of the
project’s landscaped areas.

Yes
N4. BMP Maintenance In order to ensure adequate and comprehensive BMP implementation, all responsible parties are identified for implementing all non-structural and structural BMPs, cleaning, inspection, and other maintenance activities are specified including responsible parties for conducting such activities.

A minimum 2 Inspections/ Cleanings per
year per manufacturer’s specifications prior
to October 1st (before the rainy season)
HOA/ OWNER to hire
professional BMP maintenance
company to conduct regular
inspections, repairs, and
cleaning per manufacturer’s
specifications.

Yes
N5. Title 22 CCR Compliance Hazardous waste is managed properly through compliance with applicable Title 22 regulations. Hazardous materials or wastes will be generated, handled, transported, or disposed of in association with the project; measures are taken to comply with At time of hiring, leasing and/ or home
purchase.

The distribution of these
materials will be the
responsibility of the HOA at
the time of hire, lease
signing or home purchase
per property owner, tenant,

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applicable local, state, and federal regulation to avoid harm to humans and the environment. or occupant or at the initial
time of hiring.

No N7. Spill Contingency Plan No N8. Underground Storage Tank Compliance Yes
N10. Uniform Fire Code Implementation HOA/ OWNER to comply with fire regulations and keep informed of the latest rules and requirements.

Comply with annual fire inspections and
maintain building and access per the latest
fire codes. HOA/ OWNER
Yes
N11. Common Area Litter Control The proposed project will have various trash receptacles located near the common areas. Trash management and litter control procedures are specified within this report, including responsible parties, and implemented to reduce pollution of drainage water.

Once per week provide litter removal of site
parking lot and landscape areas and to
empty common area trash bins.

HOA/ OWNER
Yes
N12. Employee Training Practical informational materials and/or training are provided to employees at the initial time of hiring by the HOA/ OWNER to increase their understanding of stormwater quality, sources of pollutants, and their responsibility for reducing pollutants in stormwater.

The distribution of these materials will be
the responsibility of the HOA/ OWNER at the
initial hiring of the employee.

HOA/ OWNER
No N13. Housekeeping of Loading Docks
Yes
N14. Common Area Catch Basin Inspection In order to ensure adequate and comprehensive BMP implementation, all responsible parties are identified for implementing all non-structural and structural BMPs, cleaning, inspection, and other maintenance activities are specified including responsible parties for conducting such activities.

Inspection twice per month of common
areas where catch basins are located within
the surrounding area and remove any trash/
debris.

HOA/ OWNER
Yes
N15. Street Sweeping Private Streets and Parking Lots Regular sweeping is conducted to reduce pollution of drainage water.

City’s Street Sweeping Services or approved
Private Company on a weekly basis HOA/ OWNER
No N17. Retail Gasoline Outlets
Structural Source Control BMPs

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Yes
S1. Provide Storm Drain System Stenciling and Signage
Catch Basin Stenciling and Signage will be placed on all on-site catch basins to the satisfaction of the City Engineer.

Inspect and repair as needed all onsite
storm drain stencilling & signage. Inspection
should occur at minimum twice per year.

HOA/ OWNER
No S2. Design and Construct Outdoor Material Storage Areas to Reduce Pollutant Introduction No S3. Design and Construct Trash and Waste Storage Areas to Reduce Pollutant Introduction (trash enclosures) Yes
S4. Use Efficient Irrigation Systems and Landscape Design Site efficient irrigation and landscaping has been implemented by the project’s landscape architect to the satisfaction of the City Engineer and Planning Department.

HOA/ OWNER to provide maintenance of
landscaping to meet current water efficiency standards and keep plants healthily. Regular maintenance once a week and monthly
inspection to determine any water
deficiencies.

The HOA/ OWNER will
maintain or hire professionals
to manage the upkeep of the
project’s landscaped areas.

Yes
S5. Protect Slopes and Channels In order to ensure proper function of stormwater facilities and reduce pollution of drainage water.

HOA/ Owner to inspect drainage channels
and remove and trash/debris.

Inspection/cleaning should occur at least
twice per year

HOA/ OWNER
No S6. Loading Docks Areas No S7. Maintenance Bays and Docks No S8. Vehicle Wash Areas No S9. Outdoor Processing Areas No S10. Equipment Wash Areas No S11. Fueling Areas No S12. Site Design and Landscape Planning No S13. Wash Water Controls for Food Preparation Area No S14. Community Car Wash Racks Low Impact Development BMPs
Yes
Treatment Control BMP #1 Connector Pipe Screen (CPS) Device See attached for specific BMP detailed information pertaining to operation and maintenance.

Inspections/ Cleanings should
occur at least two times per
year and before the start of
the rainy season (October 1st).

Refer to manufacturer’s specifications for
additional information.

HOA/ OWNER will be required
to hire a professional
maintenance company to
provide regular inspection,
repairs, and cleaning per
manufacturer’s specifications.

All trash/ debris and loose
sediment/ silt shall be removed
per manufacturer’s
specifications.

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Yes
Treatment Control BMP Modular Wetlands System Biofiltration Vault & Dvert System See attached for specific BMP detailed information pertaining to operation and maintenance.

Inspections/ Cleanings should
occur at least two times per
year and before the start of
the rainy season (October 1st).

Refer to manufacturer’s specifications for
additional information.

HOA/ OWNER will be required
to hire a professional
maintenance company to
provide regular inspection,
repairs, and cleaning per
manufacturer’s specifications.

All trash/ debris and loose
sediment/ silt shall be removed
per manufacturer’
specifications.

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Required Permits
This section must list any permits required for the implementation, operation, and maintenance of the BMPs. Possible examples are:
• No required permits are needed for the implementation, operation, and maintenance of the previously listed BMPs.

Forms to Record the BMP Implementation, Maintenance, and Inspection The form that will be used to record the implementation, maintenance, and inspection of the BMPs is attached.

Recordkeeping
All records must be maintained for at least five (5) years and must be made available for review upon request.

Notice to Owner:

The property is currently owned by KB Home. The Owner will be responsible for the long-term maintenance of the project’s storm water facilities and conformance to this WQMP after construction is complete.

The owner is aware of the maintenance responsibilities of the proposed BMPs. A funding mechanism is in place to maintain the BMPs at the frequency stated in the WQMP.

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RECORD OF BMP IMPLEMENTATION, MAINTENANCE, AND INSPECTION Today’s Date:

Name of Person Performing Activity:
(Printed)

Signature:

BMP Name
(As Shown on O&M Plan)
Brief Description of Implementation,
Maintenance, and Inspection Activity Performed

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Operation & Maintenance Plan - Attachments
• Modular Wetlands System, Maintenance Guidelines
• Connector Pipe Screen (CPS), Operation & Maintenance Manual

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Modular Wetland System (MWS) – LINEAR
Maintenance Cost (per acre)
MWS - LINEAR Cleaning Required
Yearly
Maintenance
Cost
Year 1
1) Clean Inlet Filter (6 Month Intervals)
2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media
$80 / each (x2)
$350 / year
$500 / year
Year 2
1) Clean Inlet Filter (6 Month Intervals)
2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media
$80 / each (x2)
$350 / year
$500 / year
Year 3
1) Clean Inlet Filter (6 Month Intervals)
2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media
$80 / each (x2)
$350 / year
$500 / year
Year 4
1) Clean Inlet Filter (6 Month Intervals)
2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media
$80 / each (x2)
$350 / year
$500 / year
Year 5
1) Clean Inlet Filter (6 Month Intervals)
2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media
$80 / each (x2)
$350 / year
$500 / year
Year 6
1) Clean Inlet Filter (6 Month Intervals)
2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media
$80 / each (x2)
$350 / year
$500 / year
Year 7
1) Clean Inlet Filter (6 Month Intervals)
2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media
$80 / each (x2)
$350 / year
$500 / year
Year 8
1) Clean Inlet Filter (6 Month Intervals)
2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media
$80 / each (x2)
$350 / year
$500 / year
Year 9
1) Clean Inlet Filter (6 Month Intervals)
2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media
$80 / each (x2)
$350 / year
$500 / year
Year 10
1) Clean Inlet Filter (6 Month Intervals)
2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media
4) Remove & Replace Wetland Plants & Media
$80 / each (x2)
$350/ year
$500 / year
$2,500
Total 1 - 10 Total Maintenance Cost Over 10 Years $11,800 Average Yearly Cost Assumes 10 Year Replacement of Wetland Media. $1,180 / Year
WWW.MODULARWETLANDS.COM P: 760-433-7640

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www.modularwetlands.com

Inspection Guidelines for
Modular Wetland System - Linear
Inspection Summary
o Inspect Pre-Treatment, Biofiltration and Discharge Chambers – average inspection interval is 6 to 12 months.
 (15 minute average inspection time).
o NOTE: Pollutant loading varies greatly from site to site and no two sites are the same. Therefore, the first year requires inspection monthly during the wet season and every other month during the dry season in order to observe and record the amount of pollutant loading the system is receiving.

System Diagram

Access to separation chamber
and pre-filter cartridges
1 Pre-treatment Chamber
2 Biofiltration Chamber
3 Discharge Chamber
Access to discharge
chamber and orifice control

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Inspection Overview
As with all stormwater BMPs inspection and maintenance on the MWS Linear is necessary.

Stormwater regulations require that all BMPs be inspected and maintained to ensure they are operating as designed to allow for effective pollutant removal and provide protection to receiving water bodies. It is recommended that inspections be performed multiple times during the first year to assess the site specific loading conditions. This is recommended because pollutant loading and pollutant characteristics can vary greatly from site to site. Variables such as nearby soil erosion or construction sites, winter sanding on roads, amount of daily traffic and land use can increase pollutant loading on the system. The first year of inspections can be used to set inspection and maintenance intervals for subsequent years to ensure appropriate maintenance is provided. Without appropriate maintenance a BMP will exceed its storage capacity which can negatively affect its continued performance in removing and retaining captured pollutants.

Inspection Equipment
Following is a list of equipment to allow for simple and effective inspection of the MWS Linear:
 Modular Wetland Inspection Form
 Flashlight
 Manhole hook or appropriate tools to remove access hatches and covers  Appropriate traffic control signage and procedures
 Measuring pole and/or tape measure.
 Protective clothing and eye protection.
 7/16” open or closed ended wrench.
 Large permanent black marker (initial inspections only – first year)  Note: entering a confined space requires appropriate safety and certification. It is generally not required for routine inspections of the system.

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Inspection Steps
The core to any successful stormwater BMP maintenance program is routine inspections. The inspection steps required on the MWS Linear are quick and easy. As mentioned above the first year should be seen as the maintenance interval establishment phase. During the first year more frequent inspections should occur in order to gather loading data and maintenance requirements for that specific site. This information can be used to establish a base for long term inspection and maintenance interval requirements.

The MWS Linear can be inspected though visual observation without entry into the system. All necessary pre-inspection steps must be carried out before inspection occurs, especially traffic control and other safety measures to protect the inspector and near-by pedestrians from any dangers associated with an open access hatch or manhole. Once these access covers have been safely opened the inspection process can proceed:
 Prepare the inspection form by writing in the necessary information including project name, location, date & time, unit number and other info (see inspection form).  Observe the inside of the system through the access hatches. If minimal light is available and vision into the unit is impaired utilize a flashlight to see inside the system and all of its chambers.
 Look for any out of the ordinary obstructions in the inflow pipe, pre-treatment chamber, biofiltration chamber, discharge chamber or outflow pipe. Write down any observations on the inspection form.
 Through observation and/or digital photographs estimate the amount of trash, debris and sediment accumulated in the pre-treatment chamber. Utilizing a tape measure or measuring stick estimate the amount of trash, debris and sediment in this chamber. Record this depth on the inspection form.

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 Through visual observation inspect the condition of the pre-filter cartridges. Look for excessive build-up of sediments on the cartridges, any build-up on the top of the cartridges, or clogging of the holes. Record this information on the inspection form. The pre-filter cartridges can further be inspected by removing the cartridge tops and assessing the color of the BioMediaGREEN filter cubes (requires entry into pre-treatment chamber – see notes above regarding confined space entry). Record the color of the material. New material is a light green in color. As the media becomes clogged it will turn darker in color, eventually becoming dark brown or black. Using the below color indicator record the percentage of media exhausted.  The biofiltration chamber is generally maintenance free due to the system’s advanced pretreatment chamber. For units which have open planters with vegetation it is recommended that the vegetation be inspected. Look for any plants that are dead or showing signs of disease or other negative stressors. Record the general health of the plants on the inspection and indicate through visual observation or digital photographs if trimming of the vegetation is needed.
 The discharge chamber houses the orifice control structure, drain down filter and is connected to the outflow pipe. It is important to check to ensure the orifice is in proper operating conditions and free of any obstructions. It is also important to assess the condition of the drain down filter media which utilizes a block form of the BioMediaGREEN. Assess in the same manner as the cubes in the Pre-Filter Cartridge as mentioned above. Generally, the discharge chamber will be clean and free of debris. Inspect the water marks on the side walls. If possible, inspect the discharge chamber during a rain event to assess the amount of flow leaving the system while it is at 100% capacity (pre-treatment chamber water level at peak HGL). The water level of the flowing water should be compared to the watermark level on the side walls which is an indicator of the highest discharge rate the system achieved when initially installed.

Record on the form is there is any difference in level from watermark in inches. 0% -- Percent Clogged -- 100%
New
BioMediaGREEN
Exhausted
BioMediaGREEN
85%

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www.modularwetlands.com
 NOTE: During the first few storms the water level in the outflow chamber should be observed and a 6” long horizontal watermark line drawn (using a large permanent marker) at the water level in the discharge chamber while the system is operating at 100% capacity. The diagram below illustrates where a line should be drawn. This line is a reference point for future inspections of the system:
 Water level in the discharge chamber is a function of flow rate and pipe size. Observation of water level during the first few months of operation can be used as a benchmark level for future inspections. The initial mark and all future observations shall be made when system is at 100% capacity (water level at maximum level in pre-treatment chamber). If future water levels are below this mark when system is at 100% capacity this is an indicator that maintenance to the pre-filter cartridges may be needed.  Finalize inspection report for analysis by the maintenance manager to determine if maintenance is required.

Water Level
Mark
Water Level
Marks
Using a permanent marker draw a 6 inch long horizontal line, as shown, at the higher water level in the MWS Linear discharge chamber.

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Maintenance Indicators

Based upon observations made during inspection, maintenance of the system may be required based on the following indicators:
 Missing or damaged internal components or cartridges.  Obstructions in the system or its inlet or outlet.
 Excessive accumulation of floatables in the pre-treatment chamber in which the length and width of the chamber is fully impacted more than 18”.
 Excessive accumulation of sediment in the pre-treatment chamber of more than 6” in depth.

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 Excessive accumulation of sediment on the BioMediaGREEN media housed within the prefilter cartridges. The following chart shows photos of the condition of the BioMediaGREEN contained within the pre-filter cartridges. When media is more than 85% clogged replacement is required.
 Excessive accumulation of sediment on the BioMediaGREEN media housed within the drain down filter. The following photos show of the condition of the BioMediaGREEN contained within the drain down filter. When media is more than 85% clogged replacement is required. 0% -- Percent Clogged -- 100%
New
BioMediaGREEN
Exhausted
BioMediaGREEN
85%

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 Overgrown vegetation.
 Water level in discharge chamber during 100% operating capacity (pre-treatment chamber water level at max height) is lower than the watermark by 20%.

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Inspection Notes

1. Following maintenance and/or inspection, it is recommended the maintenance operator prepare a maintenance/inspection record. The record should include any maintenance activities performed, amount and description of debris collected, and condition of the system and its various filter mechanisms.

2. The owner should keep maintenance/inspection record(s) for a minimum of five years from the date of maintenance. These records should be made available to the governing municipality for inspection upon request at any time.

3. Transport all debris, trash, organics and sediments to approved facility for disposal in accordance with local and state requirements.

4. Entry into chambers may require confined space training based on state and local regulations.

5. No fertilizer shall be used in the Biofiltration Chamber.

6. Irrigation should be provided as recommended by manufacturer and/or landscape architect. Amount of irrigation required is dependent on plant species. Some plants may not require irrigation after initial establishment.

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Maintenance Guidelines for
Modular Wetland System - Linear
Maintenance Summary
o Remove Sediment from Pre-Treatment Chamber – average maintenance interval is 12 to 24 months.
 (10 minute average service time).
o Replace Pre-Filter Cartridge Media – average maintenance interval 12 to 24 months.  (10-15 minute per cartridge average service time).
o Trim Vegetation – average maintenance interval is 6 to 12 months.  (Service time varies).

System Diagram

Access to separation chamber
and pre-filter cartridge
1 Pre-treatment Chamber
2 Biofiltration Chamber
3 Discharge Chamber

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Maintenance Overview
The time has come to maintain your Modular Wetland System Linear (MWS Linear). To ensure successful and efficient maintenance on the system we recommend the following. The MWS Linear can be maintained by removing the access hatches over the systems various chambers. All necessary pre-maintenance steps must be carried out before maintenance occurs, especially traffic control and other safety measures to protect the inspector and near-by pedestrians from any dangers associated with an open access hatch or manhole. Once traffic control has been set up per local and state regulations and access covers have been safely opened the maintenance process can begin. It should be noted that some maintenance activities require confined space entry. All confined space requirements must be strictly followed before entry into the system. In addition the following is recommended:
 Prepare the maintenance form by writing in the necessary information including project name, location, date & time, unit number and other info (see maintenance form).  Set up all appropriate safety and cleaning equipment.  Ensure traffic control is set up and properly positioned.  Prepare a pre-checks (OSHA, safety, confined space entry) are performed.

Maintenance Equipment
Following is a list of equipment required for maintenance of the MWS Linear:
 Modular Wetland Maintenance Form
 Manhole hook or appropriate tools to access hatches and covers  Protective clothing, flashlight and eye protection.
 7/16” open or closed ended wrench.
 Vacuum assisted truck with pressure washer.
 Replacement BioMediaGREEN for Pre-Filter Cartridges if required (order from manufacturer).

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Maintenance Steps

1. Pre-treatment Chamber (bottom of chamber)
A. Remove access hatch or manhole cover over pre-treatment chamber and position vacuum truck accordingly.

B. With a pressure washer spray down pollutants accumulated on walls and pre-filter cartridges.

C. Vacuum out Pre-Treatment Chamber and remove all accumulated pollutants including trash, debris and sediments. Be sure to vacuum the floor until pervious pavers are visible and clean.

D. If Pre-Filter Cartridges require media replacement move onto step 2. If not, replace access hatch or manhole cover.

Removal of access hatch to gain access below. Insertion of vacuum hose into separation chamber.

Removal of trash, sediment and debris. Fully cleaned separation chamber.

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2. Pre-Filter Cartridges (attached to wall of pre-treatment chamber) A. After finishing step 1 enter pre-treatment chamber.

B. Unscrew the two bolts holding the lid on each cartridge filter and remove lid.

C. Place the vacuum hose over each individual media filter to suck out filter media.

D. Once filter media has been sucked use a pressure washer to spray down inside of the cartridge and it’s containing media cages. Remove cleaned media cages and place to the side. Once removed the vacuum hose can be inserted into the cartridge to vacuum out any remaining material near the bottom of the cartridge.

Pre-filter cartridges with tops on.

Inside cartridges showing media filters ready for
replacement.

Vacuuming out of media filters.

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E. Reinstall media cages and fill with new media from manufacturer or outside supplier.

Manufacturer will provide specification of media and sources to purchase. Utilize the manufacture provided refilling trey and place on top of cartridge. Fill trey with new bulk media and shake down into place. Using your hands slightly compact media into each filter cage. Once cages are full removed refilling trey and replace cartridge top ensuring bolts are properly tightened.

F. Exit pre-treatment chamber. Replace access hatch or manhole cover.

3. Biofiltration Chamber (middle vegetated chamber)
A. In general, the biofiltration chamber is maintenance free with the exception of maintaining the vegetation. Using standard gardening tools properly trim back the vegetation to healthy levels. The MWS Linear utilizes vegetation similar to surrounding landscape areas therefore trim vegetation to match surrounding vegetation. If any plants have died replace plants with new ones:

Refilling trey for media replacement. Refilling trey on cartridge with bulk media.

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4. Discharge Chamber (contains drain down cartridge & connected to pipe) A. Remove access hatch or manhole cover over discharge chamber.

B. Enter chamber to gain access to the drain down filter. Unlock the locking mechanism and left up drain down filter housing to remove used BioMediaGREEN filter block as shown below:

C. Insert new BioMediaGREEN filter block and lock drain down filter housing back in place.

Replace access hatch or manhole cover over discharge chamber.

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Inspection Notes

3. Transport all debris, trash, organics and sediments to approved facility for disposal in accordance with local and state requirements.

4. Entry into chambers may require confined space training based on state and local regulations.

5. No fertilizer shall be used in the Biofiltration Chamber.

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For Office Use Only
(city) (Zip Code) (Reviewed By)
Owner / Management Company
(Date)
Contact Phone ( ) _
Inspector Name Date / / Time AM / PM
Weather Condition Additional Notes
Yes
Depth:

Yes No
Modular Wetland System Type (Curb, Grate or UG Vault): Size (22', 14' or etc.):

Other Inspection Items:

Type of Inspection Routine Follow Up Complaint Storm Storm Event in Last 72-hours? No Yes Office personnel to complete section to
the left.
2972 San Luis Rey Road, Oceanside, CA 92058 P (760) 433-7640 F (760) 433-3176 Inspection Report
Modular Wetlands System

Is the filter insert (if applicable) at capacity and/or is there an accumulation of debris/trash on the shelf system? Does the cartridge filter media need replacement in pre-treatment chamber and/or discharge chamber? Any signs of improper functioning in the discharge chamber? Note issues in comments section.

Chamber:

Is the inlet/outlet pipe or drain down pipe damaged or otherwise not functioning properly? Structural Integrity:

Working Condition:

Is there evidence of illicit discharge or excessive oil, grease, or other automobile fluids entering and clogging the unit?
Is there standing water in inappropriate areas after a dry period? Damage to pre-treatment access cover (manhole cover/grate) or cannot be opened using normal lifting pressure?
Damage to discharge chamber access cover (manhole cover/grate) or cannot be opened using normal lifting pressure?
Does the MWS unit show signs of structural deterioration (cracks in the wall, damage to frame)? Project Name
Project Address
Inspection Checklist
No Comments
Does the depth of sediment/trash/debris suggest a blockage of the inflow pipe, bypass or cartridge filter? If yes, specify which one in the comments section. Note depth of accumulation in in pre-treatment chamber.

Is there a septic or foul odor coming from inside the system? Is there an accumulation of sediment/trash/debris in the wetland media (if applicable)? Is it evident that the plants are alive and healthy (if applicable)? Please note Plant Information below.

Sediment / Silt / Clay
Trash / Bags / Bottles
Green Waste / Leaves / Foliage
Waste: Plant Information
No Cleaning Needed
Recommended Maintenance
Additional Notes:

Damage to Plants
Plant Replacement
Plant Trimming
Schedule Maintenance as Planned
Needs Immediate Maintenance

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For Office Use Only
(city) (Zip Code) (Reviewed By)
Owner / Management Company
(Date)
Contact Phone ( ) _
Inspector Name Date / / Time AM / PM
Weather Condition Additional Notes
Site
Map #
Comments:
2972 San Luis Rey Road, Oceanside, CA 92058 P. 760.433.7640 F. 760.433.3176 Inlet and Outlet
Pipe Condition
Drain Down Pipe
Condition
Discharge Chamber
Condition
Drain Down Media
Condition
Plant Condition
Media Filter
Condition
Long:

MWS
Sedimentation
Basin
Total Debris
Accumulation
Condition of Media
25/50/75/100
(will be changed
@ 75%)
Operational Per
Manufactures'
Specifications
(If not, why?)
Lat: MWS
Catch Basins
GPS Coordinates
of Insert
Manufacturer /
Description / Sizing
Trash
Accumulation
Foliage
Accumulation
Sediment
Accumulation
Type of Inspection Routine Follow Up Complaint Storm Storm Event in Last 72-hours? No Yes Office personnel to complete section to
the left.

Project Address
Project Name
Cleaning and Maintenance Report
Modular Wetlands System

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Modular Wetland System - Linear (MWS-Linear)
Maintenance Schedule
MWS - LINEAR Cleaning Required Est. Cleaning
Time
Year 1 1) Clean Inlet Filter (6 Month Intervals) (does not apply to vault type) 2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media (12 month Intervals) 10 Minutes
25 Minutes
45 Minutes
Year 2 1) Clean Inlet Filter (6 Month Intervals) (does not apply to vault type) 2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media (12 month Intervals) 10 Minutes
25 Minutes
45 Minutes
Year 3 1) Clean Inlet Filter (6 Month Intervals) (does not apply to vault type) 2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media (12 month Intervals) 10 Minutes
25 Minutes
45 Minutes
Year 4 1) Clean Inlet Filter (6 Month Intervals) (does not apply to vault type) 2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media (12 month Intervals) 10 Minutes
25 Minutes
45 Minutes
Year 5 1) Clean Inlet Filter (6 Month Intervals) (does not apply to vault type) 2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media (12 month Intervals) 10 Minutes
25 Minutes
45 Minutes
Year 6 1) Clean Inlet Filter (6 Month Intervals) (does not apply to vault type) 2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media (12 month Intervals) 10 Minutes
25 Minutes
45 Minutes
Year 7 1) Clean Inlet Filter (6 Month Intervals) (does not apply to vault type) 2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media (12 month Intervals) 10 Minutes
25 Minutes
45 Minutes
Year 8 1) Clean Inlet Filter (6 Month Intervals) (does not apply to vault type) 2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media (12 month Intervals) 10 Minutes
25 Minutes
45 Minutes
Year 9… 1) Clean Inlet Filter (6 Month Intervals) (does not apply to vault type) 2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media (12 month Intervals) 10 Minutes
25 Minutes
45 Minutes
Year 15
1) Clean Inlet Filter (6 Month Intervals) (does not apply to vault type) 2) Vacuum Catch Basin (12 Month Intervals)
3) Replace BioMedia Green Filter Media (12 month Intervals) 4) Remove & Replace Wetland Plants & Media (every 10-20 years) 10 Minutes
25 Minutes
45 Minutes
6 to 8 Hours
Procedure 1
Clean Inlet Filter
(does not apply to vault type)
Modular Wetland Systems, Inc. recommends the catch basin filter be inspected and cleaned a minimum of once every six months and replacement of hydrocarbon booms once a year. The procedure is easily done with the use of any standard vacuum truck. Before doing maintenance please use proper safety and traffic control. 1) Remove grate or manhole, remove the deflector shield (grate type only). Note: entry into an underground stormwater vault such as an inlet vault requires certification in confined space training. 2) Remove all trash, debris, organics, and sediments collected by the inlet filter insert either manually or with the use of a vactor truck.
3) Evaluate hydrocarbon boom. If the boom is filled with hydrocarbons and oils it should be replaced. Attach new boom to basket with plastic ties through pre-drilled holes in basket. Place the deflector shield (grate type only) back into the filter.

Hydrocarbon boom should be replaced annually. (The hydrocarbon boom may be classified as hazardous material and will have to be picked up and disposed of as hazardous waste). 10 Minutes

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Procedure 2
Vacuum Catch Basin
Modular Wetland Systems, Inc. recommends the separation chamber be inspected and cleaned a minimum of once a year. The procedure is easily done with the use of any standard vacuum truck. Before doing maintenance please use proper safety and traffic control.
1) Remove grate or manhole.
2) Remove catch basin filter.
3) Spray down pollutants accumulated on cartridge filters and catch basin walls. 4) Vacuum out sediments and debris accumulated on catch basin floor. 5) Replace catch basin filter, and replace grate or manhole cover. 25 Minutes
Procedure 3
Replace BioMedia
Green Media Filter
Modular Wetland Systems, Inc. recommends the BioMediaGREEN Cartridge Filters be inspected and cleaned a minimum of once a year. The procedure will require prior maintenance of catch basin. Before doing maintenance please use proper safety and traffic control.
1) Remove grate, remove catch basin filter.
2) Perform maintenance activities on catch basin.
3) Enter separation chamber, unscrew the two bolts holding the lid on the cartridge filter. This will expose the 14 pieces of BioMediaGREEN in each cartridge. 4) Evaluate media condition, replace if necessary. If the spaces between the media are filled with sediment and the surface of the media is dark brown or black the media should be replaced. The old media can be removed by hand by pulling the media pieces up out of the cartridge and taking them out of the catch basin. 5) Once all old media is removed, spray down the interior of the cartridge and vacuum out accumulated debris.
6) Use new pieces of BioMediaGREEN and slide down over the perforated PVC risers. The media will only go in one way for easy installation. Replace media over all risers.
5) Replace cartridge filter lid, replace catch basin filter, and replace grate or manhole cover.

Modular Wetland Systems, Inc. recommends the drain down filter be inspected and maintained a minimum of once a year.
1) Open hatch of discharge chamber, enter chamber.
2) Unlatch fiberglass cover, remove media block, replace with new block, replace and latch cover.
3) Exit chamber, close and lock down the hatch.
45 Minutes
Procedure 4
Replace Wetland
Media
Modular Wetland Systems, Inc. recommends the wetland media be evaluated every 3 to 5 years to test flow rate. The media life is approximately 15 to 20 years. The wetland media is an expanded shale that can be ordered from the manufacturer or independent supplier. If the flow through the wetland filter is decreasing the internal inflow and outflow pipes leading to and from the wetland chamber can be jetted. If the flow through the wetland is still minimal then the media may need to be replaced. To replace the media the following steps are required. Before doing maintenance please use proper safety and traffic control.
1) Remove plants and dispose. Have new plants standing ready to plant. 2) Use a larger vacuum truck to remove the media from the wetland chamber. 3) Spray down the chamber walls and remove all sediment and water. 4) Replace with new wetland media and plant plants.
6 to 8 Hours
WWW.MODULARWETLANDS.COM P: 760-433-7640

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Bio Clean CPS
A Stormwater Trash Capture Solution
A Forterra Company

OPERATION & MAINTENANCE
MANUAL
5796 Armada Drive Suite 250 | Carlsbad, CA 92008 | 855.566.3938 [email protected] | biocleanenvironmental.com Page 1529 of 2028 1 | Page

OPERATION & MAINTENANCE
CPS devices should be maintained by individuals who are trained in proper disposal procedures, confined space entry and traffic safety regulations. When servicing a Bio Clean CPS device be sure to follow all safety and traffic control protocols as well as wearing all proper personal protection equipment such as gloves, safety glasses, hard-hat, safety vest and work boots.

Visual Inspection

1. Begin by inspecting the inflow of the catch basin where the Bio Clean CPS device is located.

Check for any obstructions to inflow of the CB unit. If any large obstructions are found, have them removed. Once the inflow inspection is completed, remove the man-hole cover for further inspection. (Note: Confined Space Entry Procedures may apply if trained personnel intend to enter the interior space of any Catch Basin. Please follow all applicable confined space entry procedures)

2. Remove the manhole cover and visually estimate the amount and types of debris found in the CB unit. Look for any visual signs of damage that may compromise the CB unit to function properly.

Inspect for any standing water in the CB unit as well as for large amounts of sediment and debris surrounding the CPS device. If standing water and high sediment volume is found, remove water, sediment and debris by vacuum truck or by other debris removal methods.

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2 | Page
Cleaning Procedures and Frequencies

1. Like all other storm water BMP’s, Bio Clean CPS devices require periodic maintenance.

Routine inspection and maintenance intervals for all CPS devices are typically twice per year for inspections and once per year for maintenance service. Bio Clean CPS devices may require more frequent maintenance service if the device is located in a high debris loading drainage area, such as certain downtown areas, retail/restaurant, or residential areas where a significant amount of vegetation/foliage is located. In such cases, Bio Clean CPS devices may require more frequent inspection and maintenance service, which could range from twice per year to monthly inspection and maintenance service, depending on pollutant load conditions.

2. To begin Bio Clean CPS cleaning procedures, conduct a visual inspection of the CPS device and the surrounding area to ensure a safe working environment. Setup appropriate barriers and signage as necessary to establish a work zone surrounding the catch basin. Once the work zone has been established, remove the manhole cover from the catch basin.

3. Once the manhole cover is removed from the basin the Bio Clean CPS is ready for servicing. All debris can be removed by either a vacuum truck or manually removing sediment and debris by hand.

4. Bio Clean CPS devices shall be cleaned using a pressure washer as may be necessary if any materials are found to cause occlusion or clogging of the screen.

Disposal

1. All trash and debris removed from the Bio Clean CPS unit shall be disposed of in accordance with local, state and federal regulation.

2. Solid waste disposal can be coordinated with local landfills. Liquids may need to be disposed of by wastewater treatment plant, municipal vacuum truck decant facility or approved facility.

For Maintenance Services or
Information Please Contact Us At:
760-433-7640
Or Email:
[email protected]

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Attachment E : Geotechnical Report

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Corona Office
Phone: 951.509.7090

CITY VENTURES DRAFT
3121 Michelson Drive, Suite 150 Project No. 1-0539
Irvine, California 92612
Attention: Mr. Patrick Chien
Subject: GEOTECHNICAL INVESTIGATION
19081 Yorba Linda Boulevard,
City of Yorba Linda, California
Dear Mr. Chien:

Alta California Geotechnical, Inc. (Alta) is pleased to present this geotechnical investigation for the proposed development at 19081 Yorba Linda Boulevard, in the City of Yorba Linda, Orange County, California. This report is based upon a recent subsurface investigation conducted by Alta, laboratory testing, a review of published geologic maps, and Alta’s staff’s experience with similar projects in this vicinity.

Alta’s review of the data indicates that the proposed development is feasible, from a geotechnical perspective, provided that the recommendations presented in this report are incorporated into the grading and improvement plans and implemented during site development.

Included in this report are:
 Discussion of the site geotechnical conditions.
 Recommendations for remedial and site grading, including unsuitable soil removals  Geotechnical site construction recommendations
 Preliminary foundation design parameters
 Preliminary Infiltration testing
 Estimate shrink/swell parameters

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Project Number 1-0568 Page ii
DRAFT
ALTA CALIFORNIA GEOTECHNICAL, INC.

If you have any questions or should you require any additional information, please contact the undersigned at (951) 509-7090. Alta appreciates the opportunity to provide geotechnical consulting services for your project.

Sincerely,
Alta California Geotechnical, Inc. Reviewed By:
________DRAFT________________________
SCOTT A. GRAY/RGE 2857
Reg. Exp.: 12-31-26
Registered Geotechnical Engineer
President
_________DRAFT_________________________
FRANK ECHENIQUE/CEG 2134
Reg. Exp.: 7-31-26
Certified Engineering Geologist
Distribution: (1) Addressee
LAM: SAG: eg-1-0568 (DRAFT, January 2025) Geotechnical Investigation,CV Yorba Linda)

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Project Number 1-0568 Page iii
DRAFT
ALTA CALIFORNIA GEOTECHNICAL, INC.

1.0 INTRODUCTION ................................................................................................................... 1

1.1 Purpose ......................................................................................................................... 1

1.2 Scope of Work ............................................................................................................... 1

1.3 Report Limitations ......................................................................................................... 2

2.0 PROJECT DESCRIPTION ........................................................................................................ 2

2.1 Site Location and Existing Conditions ............................................................................ 2

2.2 Proposed Development ................................................................................................. 2

3.0 SITE INVESTIGATION ............................................................................................................ 3

3.1 Current Subsurface Investigation .................................................................................. 3

3.2 Infiltration Testing ......................................................................................................... 3

4.0 GEOLOGIC CONDITIONS ...................................................................................................... 4

4.1 Geologic and Geomorphic Setting ................................................................................. 4

4.2 Stratigraphy ................................................................................................................... 4

4.2.1 Very Old Alluvial Fan Deposits (Map symbol Qvof) ............................................... 4

4.3 Geologic Structure ......................................................................................................... 4

4.3.1 Tectonic Framework .............................................................................................. 4

4.3.2 Regionally Mapped Active Faults ........................................................................... 5

4.3.3 Geologic Structures ............................................................................................... 5

4.4 Groundwater ................................................................................................................. 5

4.5 Earthquake Hazards ...................................................................................................... 5

4.5.1 Local and Regional Faulting ................................................................................... 6

4.5.2 Seismicity ............................................................................................................... 6

4.5.3 Surface Rupture ..................................................................................................... 6

4.5.4 Liquefaction ........................................................................................................... 6

4.5.5 Dry Sand Settlement .............................................................................................. 7

4.6 Regional Subsidence ...................................................................................................... 7

5.0 ENGINEERING PROPERTIES AND ANALYSIS ......................................................................... 7

5.1 Materials Properties ...................................................................................................... 7

5.1.1 Excavation Characteristics ..................................................................................... 7

5.1.2 Compressibility ...................................................................................................... 8

5.1.3 Moisture ................................................................................................................ 8

5.1.4 Hydro-Consolidation .............................................................................................. 8

5.1.5 Expansion Potential ............................................................................................... 8

5.1.6 Earthwork Adjustments ......................................................................................... 9

5.1.7 Chemical Analyses ................................................................................................. 9

5.2 Engineering Analysis ...................................................................................................... 9

5.2.1 Bearing Capacity and Lateral Earth Pressures ...................................................... 10

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Project Number 1-0568 Page iv
DRAFT
ALTA CALIFORNIA GEOTECHNICAL, INC.

6.0 CONCLUSIONS AND RECOMMENDATIONS ........................................................................ 10

6.1.1 Site Preparation ................................................................................................... 10

6.1.2 Unsuitable Soil Removals .................................................................................... 10

6.2 General Earthwork Recommendations........................................................................ 11

6.2.1 Compaction Standards ........................................................................................ 11

6.2.2 Groundwater/Seepage ........................................................................................ 12

6.2.3 Documentation of Removals ............................................................................... 12

6.2.4 Treatment of Removal Bottoms .......................................................................... 12

6.2.5 Fill Placement ...................................................................................................... 12

6.2.6 Moisture Content ................................................................................................ 13

6.2.7 Mixing .................................................................................................................. 13

6.2.8 Import Soils ......................................................................................................... 13

6.2.9 Utility Trenches ................................................................................................... 13

6.2.9.1 Excavation ............................................................................................................. 13

6.2.9.2 Backfill ................................................................................................................... 14

6.2.10 Backcut Stability .................................................................................................. 15

6.3 Storm Water Infiltration Systems ................................................................................ 15

6.4 Boundary Conditions ................................................................................................... 16

7.0 DESIGN CONSIDERATIONS ................................................................................................. 16

7.1 Structural Design ......................................................................................................... 16

7.1.1 Foundation Design ............................................................................................... 17

7.1.1 Conventional Foundation Systems ...................................................................... 17

7.1.2 Post-Tensioned Slabs/Foundation Design Recommendations ............................. 18

7.2 Moisture Barrier .......................................................................................................... 19

7.3 Seismic Design ............................................................................................................. 20

7.4 Block Walls .................................................................................................................. 21

7.5 Footing Excavations ..................................................................................................... 21

7.6 Retaining Wall Design .................................................................................................. 21

7.7 Exterior Slabs and Walkways ....................................................................................... 23

7.7.1 Subgrade Compaction ......................................................................................... 23

7.7.2 Subgrade Moisture .............................................................................................. 23

7.7.3 Concrete Slab Thickness ...................................................................................... 23

7.7.4 Concrete Slab Reinforcement .............................................................................. 23

7.7.5 Control Joints ....................................................................................................... 24

7.8 Concrete Design .......................................................................................................... 24

7.9 Corrosion ..................................................................................................................... 24

7.10 Pavement Design ......................................................................................................... 25

7.11 Site Drainage ............................................................................................................... 26

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Project Number 1-0568 Page v
DRAFT
ALTA CALIFORNIA GEOTECHNICAL, INC.

8.0 LOT MAINTENANCE ........................................................................................................... 26

8.1 Lot Drainage ................................................................................................................ 26

8.2 Burrowing Animals ...................................................................................................... 27

9.0 FUTURE PLAN REVIEWS ..................................................................................................... 27

10.0 CLOSURE ...................................................................................................................... 27

10.1 Geotechnical Review ................................................................................................... 27

10.2 Limitations ................................................................................................................... 28 APPENDIX A – References
APPENDIX B – Subsurface Investigation
APPENDIX C – Laboratory Testing
APPENDIX D – Maintenance and Improvement Considerations APPENDIX E – Earthwork Specifications
APPENDIX F – Grading Details

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Project Number 1-0539 Page 1
July 24, 2024
ALTA CALIFORNIA GEOTECHNICAL, INC.

1.0 INTRODUCTION
The following report presents Alta’s findings, conclusions, and geotechnical recommendations for the proposed development of located in the City of Yorba Linda, California.

1.1 Purpose
The purpose of this report is to examine the existing geotechnical conditions and evaluate their impacts on the proposed development. This report is suitable for submittal to governing agencies and for use as a bid document.

1.2 Scope of Work
Alta’s Scope of Work for this geotechnical investigation included the following:
 Review of the referenced literature, maps, and aerial photos (Appendix A).
 Site geologic mapping.
 Excavating, logging, and sampling of five (5) hollow stem auger borings to a maximum depth of approximately 51 feet below existing grade (Appendix B).
 Drill two (2) shallow additional borings for infiltration study and perform preliminary infiltration testing.
 Conducting laboratory testing on samples obtained during our investigation (Appendix C).
 Evaluating engineering geologic and geotechnical engineering data, including laboratory data, to develop recommendations for site remedial grading, import soil, foundations and utilities.
 Preparing this report and accompanying exhibits.

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Project Number 1-0568 Page 2
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1.3 Report Limitations
The conclusions and recommendations in this report are based on the information generated during this investigation and our review of the referenced reports. The materials adjacent to or beneath those observed may have different characteristics than those observed, and no representations are made as to the quality or extent of the materials not observed.

2.0 PROJECT DESCRIPTION

2.1 Site Location and Existing Conditions
The rectangular shaped ±3.9-acre site is relatively flat and consists of singlefamily residences. The site is bounded to the north by a residential property, to the west by a residential property and synagogue, to the east by a park, and to the south by Yorba Linda Boulevard.

Historic aerial images of the site are available as far back as 1946 and indicate the site and surrounding area was comprised of citrus groves. By 1963 the single-family residences were built. The site has remained largely unchanged since, with the exception of removal of some of the trees.

Our literature review indicates that the site is underlain by mid to early Pleistocene age very old alluvial fan deposits. No known active faults have been mapped at the site or in the immediate site vicinity.

2.2 Proposed Development
Alta anticipates that the site will be developed to accommodate a multi-family residential development. Alta anticipates that conventional cut-and-fill grading techniques will be used to develop the site for the support of wood-frame construction with shallow foundations and reinforced concrete slabs-on-grade, and associated improvements.

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3.0 SITE INVESTIGATION

3.1 Current Subsurface Investigation
Alta conducted a subsurface investigation on December 9, 2024, consisting of the drilling, logging, and select sampling of five (5) hollow-stem auger borings up to a maximum depth of 51 feet below the ground surface (bgs). In addition, two (2) shallow borings (5 and 10 feet deep) were advanced to conduct preliminary infiltration testing. The locations of exploratory borings are shown on Plate 1 and the logs are presented in Appendix B.

Laboratory testing was performed on ring and bulk samples obtained during the field investigation. A brief description of the laboratory test procedures and the test results are presented in Appendix C.

3.2 Infiltration Testing
Infiltration testing was performed by Alta on December 10, 2024, utilizing percolation methods in accordance with County of Orange Storm Water Standards. Percolation rates were converted to infiltration rates utilizing the Porchet method. The resulting field infiltration rates, with no factor of safety, are presented below in Table 3-1. Recommendations for infiltration BMP design are presented in Section 6.3.

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4.0 GEOLOGIC CONDITIONS

4.1 Geologic and Geomorphic Setting
Regionally, the site is located in the Peninsular Ranges geomorphic province, which characterizes the southwest portion of Southern California. The Peninsular Ranges province is composed of Mesozoic age plutonic and metamorphic rock, lesser amounts of Tertiary age volcanic and sedimentary rock, and Quaternary age drainage in-fills and minor sediment veneers. The Peninsular Ranges are divisible into northwest-trending sub-blocks that extend south into Baja California and terminate to the north against the Transverse Ranges province.

4.2 Stratigraphy
Based on Alta’s review of geologic literature and our subsurface investigation the project site is underlain by Pleistocene age very old alluvial fan deposits (Dibblee, 2001). The following is a brief description of this geologic unit encountered during this investigation.

4.2.1 Very Old Alluvial Fan Deposits (Map symbol Qvof)
The very old alluvial fan deposits within the site consists primarily of inter-lensed silty sand, clayey sand, sand and gravelly sand that is slightly moist to moist and dense to very dense below. This unit was encountered up to 51 feet below ground surface (bgs).

4.3 Geologic Structure

4.3.1 Tectonic Framework
Jennings (1985) defined eight structural provinces within California that have been classified by predominant regional fault trends and similar fold structure. Within this framework, the subject site is located within the Peninsular Ranges geomorphic province, controlled by the dominant northwest trend of the San Andreas Fault and the subparallel San Jacinto

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Fault, Whittier/Elsinore Fault, and the Newport-Inglewood Fault, all exhibit right lateral strike-slip movement. The closest of these major faults to the site is the Whittier-Elsinore Fault, located 2.1 kilometers from the site. These fault systems have been studied extensively and in a large part control the geologic structure of the region.

4.3.2 Regionally Mapped Active Faults
Active faults in the region, including the Puente Hills Fault (6.8 kilometers from the site, which is a thrust fault, and the Whittier-Elsinore Fault (2.1 kilometers from the site), which is a strike slip fault.

4.3.3 Geologic Structures
Based upon our site investigation and literature review, the onsite subsurface is essentially flat lying sediments that do not appear to be faulted or folded.

4.4 Groundwater
Groundwater was not encountered in any borings during Alta’s recent investigation, to a depth of roughly 51 feet bgs. No nearby groundwater well data is available.

4.5 Earthquake Hazards
The subject site is located in southern California, which is a tectonically active region. The type and magnitude of seismic hazards affecting a site are dependent on the distance to the causative fault and the intensity and magnitude of the seismic event. The seismic hazard may be primary, such as surface rupture and/or ground shaking, or secondary, such as liquefaction and/or ground lurching.

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4.5.1 Local and Regional Faulting
The closest known active fault to the site is the Whittier-Elsinore Fault located 2.1 kilometers from the site. No known active faults exist below the site or in the immediate site vicinity.

4.5.2 Seismicity
Ground shaking hazards caused by earthquakes along other active regional faults exist. The 2022 California Building Code requires usemodified spectral accelerations and velocities for most structural designs.

Seismic design parameters using soil profile types identified in the 2022 California Building Code are presented in Section 7.3.

4.5.3 Surface Rupture
Active faults are not known to exist within the project and a review of Special Publication 42 indicates the site is not within a California State designated earthquake fault zone. Accordingly, the potential for fault surface rupture on the subject site is low.

4.5.4 Liquefaction
Seismic agitation of relatively loose saturated sands, silty sands, and some silts can result in a buildup of pore pressure. If the pore pressure exceeds the overburden stresses, a temporary quick condition known as liquefaction can occur. Liquefaction effects can manifest in several ways including: 1) loss of bearing; 2) lateral spread; 3) dynamic settlement; and 4) flow failure. Lateral spreading has typically been the most damaging mode of failure.

In general, the more recent that a sediment has been deposited, the more likely it will be susceptible to liquefaction. Other factors that must be considered are groundwater, confining stresses, relative density, and the intensity and duration of seismically induced ground shaking.

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Based on the fact that groundwater was not encountered in the borings during our investigation, plus the dense nature of the very old alluvial fan deposits with the removal and re-compaction recommended in this report, the potential for dynamic settlement due to liquefaction is considered to be remote.

4.5.5 Dry Sand Settlement
Dry sand settlement is the process of non-uniform settlement of the ground surface during a seismic event. Based on our subsurface investigation and our removal/recompaction recommendations, the potential for onsite dry sand settlement is anticipated to be nil.

4.6 Regional Subsidence
The site is not located in an area designated as susceptible to subsidence. Upon implementation of the remedial grading recommendations presented herein, the effects of subsidence on the development are considered to be negligible. If subsidence due to groundwater extraction were to occur, it would likely affect the entire region and not result in differential settlement across the site.

5.0 ENGINEERING PROPERTIES AND ANALYSIS

5.1 Materials Properties
Presented herein is a general discussion of the engineering properties of the onsite materials that will be encountered during construction of the proposed project. Descriptions of the soil (Unified Soil Classification System) are presented on the boring logs in Appendix B.

5.1.1 Excavation Characteristics
Based on the data provided from the subsurface investigation, it is our opinion that excavation characteristics across the site are favorable, such that conventional equipment can be utilized.

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5.1.2 Compressibility
The upper portions of the very old alluvial fan deposits are considered compressible and unsuitable to support the proposed improvements.

Recommended removal depths are presented in Section 6.1.2.

5.1.3 Moisture
The moisture content of the very old alluvial fan deposits that will require removal and recompaction as discussed in Section 6.1.2 are typically over-optimum.

5.1.4 Hydro-Consolidation
Hydro-consolidation is the effect of introducing water into soil that is prone to collapse. Upon loading and initial wetting, the soil structure and apparent strength are altered resulting in almost immediate settlement.

That settlement can have adverse impacts on engineered structures, particularly in areas where it is manifested differentially. Differential settlements are typically associated with differential wetting, irregularities in the subsurface soil conditions, or irregular loading patterns.

Based on laboratory testing results presented in Appendix C, there is minimal potential for hydro-collapse in the very old alluvial fan deposits bulks when saturated and under loading.

5.1.5 Expansion Potential
Based on expansion index testing performed during our subsurface investigation (Appendix C), the majority of soils onsite are “very low” to “low” in expansion potential (0≤EI≤50, Appendix C) when tested per ASTM D: 4829.

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5.1.6 Earthwork Adjustments
The values presented in Table 5-1 are deemed appropriate for estimating purposes and may be used to balance earthwork quantities. As is the case with every project, contingencies should be made to adjust the earthwork balance when grading is in-progress and actual conditions are better defined.

TABLE 5-1
Earthwork Adjustment Factors
Geologic Unit Adjustment Factor Range Average
Very old alluvial fan deposits
(within the upper 3 feet) Shrink 6% to 10% 8%
Very old alluvial fan deposits (below
3 feet) Shrink 0% to 4% 2%

5.1.7 Chemical Analyses
Chemical testing was performed on samples of material underlying the proposed site during our subsurface investigation. Soluble sulfate test results indicate that the soluble sulfate concentrations of the soils tested are classified as negligible (Category S0) per ACI 318-14.

Negligible chloride levels were detected in the soils onsite. Based on laboratory results of soluble sulfate, chloride, and pH testing as presented in Appendix C, the onsite soils are classified as “non-corrosive” (Caltrans, 2022). Additional discussions on corrosion are presented in Section 7.9.

5.2 Engineering Analysis
Presented below is a general discussion of the engineering analysis methods that were utilized to develop the conclusions and recommendations presented in this report.

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5.2.1 Bearing Capacity and Lateral Earth Pressures
Ultimate bearing capacity values were obtained using the graphs and formula presented in NAVFAC DM-7.1. Allowable bearing was determined by applying a factor of safety of at least 3 to the ultimate bearing capacity. Static lateral earth pressures were calculated using Rankine methods for active and passive cases. If it is desired to use Coulomb forces, a separate analysis specific to the application can be conducted.

6.0 CONCLUSIONS AND RECOMMENDATIONS
Based on Alta’s findings during our subsurface investigation, the laboratory test results, and our staff’s previous experience in the area, it is Alta’s opinion that the development of the site is feasible from a geotechnical perspective. Presented below are recommendations that should be incorporated into site development and construction plans.

6.1.1 Site Preparation
Vegetation, construction debris, and other deleterious materials are unsuitable as structural fill material and should be disposed of offsite prior to commencing grading/construction. Any septic tanks, seepage pits or wells should be abandoned as per the County of Orange Department of Health Services.

6.1.2 Unsuitable Soil Removals
The upper portions of the very old alluvial fan deposits are compressible and as such, are not suitable to support the proposed structures.

Therefore, it is anticipated that, on average, the upper three (3) to five (5) feet of existing soils will require removal and recompaction, extending a minimum of five (5) feet horizontally outside of the structures. This recommended removal combined with the foundation recommendations

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presented in Section 7.1 should provide suitable support for the proposed structures.

Footings for structures should be underlain by a minimum of two (2) feet of compacted fill. As such, for building pads where unsuitable soil removals do not provide the minimum depth of compacted fill, or where design grades and/or remedial grading activities create cut/fill transitions, the cut and shallow fill portions of the building pads should be over-excavated during grading and replaced with compacted fill.

The Project Geotechnical Consultant should observe the removal bottom prior to placing fill. If unsuitable soils such as undocumented artificial fill is exposed upon the completion of the removals recommended above, additional removals may be required.

For fill areas in parking lots/drive aisles, in general, a minimum removal and recompaction of the upper two (2) feet is recommended, however all undocumented artificial fill shall be removed and recompacted. For cuts greater than two (2) feet in street areas, removals are not required. For cuts less than two (2) feet, the two (2) foot removal and recompaction applies.

Material removed as part of the unsuitable soil removals can be used as artificial fill, provided it is free of deleterious materials.

6.2 General Earthwork Recommendations

6.2.1 Compaction Standards
All fill and processed natural ground shall be compacted to a minimum relative compaction of 90 percent, as determined by ASTM Test Method:

D-1557. Fill material should be moisture conditioned to optimum moisture or above, and as generally discussed in Alta’s Earthwork

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Specification Section presented in Appendix E. Compaction shall be achieved with the use of sheepsfoot rollers or similar kneading type equipment. Mixing and moisture conditioning will be required in order to achieve the recommended moisture conditions.

6.2.2 Groundwater/Seepage
No groundwater was encountered during our subsurface investigation.

Perched water conditions could be encountered depending on the time of year construction occurs.

6.2.3 Documentation of Removals
All removal/over-excavation bottoms should be observed and approved by the project Geotechnical Consultant prior to fill placement.

Consideration should be given to surveying the removal bottoms and undercuts after approval by the geotechnical consultant and prior to the placement of fill. Staking should be provided to verify undercut locations and depths.

6.2.4 Treatment of Removal Bottoms
At the completion of removals/over-excavation, the exposed removal bottom should be ripped to a minimum depth of eight (8) inches, moisture-conditioned to above optimum moisture content and compacted in-place to the project standards.

6.2.5 Fill Placement
After removals are completed and scarification and compaction of the removal bottom is performed, additional fill may be placed. Fill should be placed in eight-inch bulk maximum lifts, moisture conditioned to optimum moisture content or above, compacted and tested as grading/construction progresses until final grades are attained.

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6.2.6 Moisture Content
The moisture content of the upper in-situ soils varies, as shown in the boring logs presented in Appendix B. The majority of the upper several feet of onsite soils are dry to slightly moist and will require moisture conditioning prior to placement as compacted fill.

6.2.7 Mixing
Mixing of materials may be necessary to prevent layering of different soil types and/or different moisture contents. The mixing should be accomplished prior to and as part of compaction of each fill lift.

6.2.8 Import Soils
Imported soils, if necessary, should consist of clean, structural quality, low expansive, compactable materials similar to the on-site soils and should be free of trash, debris or other objectionable materials. The project Geotechnical Consultant should be notified not less than 72 hours in advance of the locations of any soils proposed for import. Import sources should be sampled, tested, and approved by the project Geotechnical Consultant at the source prior to the importation of the soils to the site. The project Civil Engineer should include these requirements on plans and specifications for the project.

6.2.9 Utility Trenches

6.2.9.1 Excavation
Utility trenches should be supported, either by laying back excavations or shoring, in accordance with applicable OSHA standards. The existing site soils are classified as Soil Type "B" per OSHA standards. Upon completion of the
recommended removals and recompaction, the artificial fill will be classified as Soil Type “B”. The Project Geotechnical

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Consulting should be consulted if geologic conditions vary from what is presented in this report.

6.2.9.2 Backfill
Utility trench backfill within the City of Fullerton backfill shall conform to the City Standard of utilizing Class II aggregate base compacted to at least 90 percent of maximum dry
density as determined by ASTM D-1557.

From a geotechnical perspective, private utility trenches may utilize onsite soils as backfill, based on approval by the governing agencies. Onsite soils will not be suitable for use as bedding material but will be suitable for use in backfill provided oversized materials are removed. No surcharge
loads should be imposed above excavations. This includes spoil piles, lumber, concrete trucks, or other construction materials and equipment. Drainage above excavations
should be directed away from the banks. Care should be
taken to avoid saturation of the soils. Compaction should be accomplished by mechanical means. Jetting of native soils will not be acceptable.

Under-slab trenches should also be compacted to project specifications. If select granular backfill (SE > 30) is used, compaction by flooding may be acceptable.

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6.2.10 Backcut Stability
Temporary backcuts, if required during unsuitable soil removals, should be made no steeper than 1:1 without review and approval of the geotechnical consultant. Flatter backcuts may be necessary where geologic conditions dictate and where minimum width dimensions are to be maintained.

Care should be taken during remedial grading operations in order to minimize risk of failure. Should failure occur, complete removal of the disturbed material will be required.

In consideration of the inherent instability created by temporary construction backcuts for removals, it is imperative that grading schedules are coordinated to minimize the unsupported exposure time of these excavations. Once started, these excavations and subsequent fill operations should be maintained to completion without intervening delays imposed by avoidable circumstances. In cases where five-day workweeks comprise a normal schedule, grading should be planned to avoid exposing at-grade or near-grade excavations through a non-work weekend. Where improvements may be affected by temporary instability, either on or offsite, further restrictions such as slot cutting, extending work days, implementing weekend schedules, and/or other requirements considered critical to serving specific circumstances may be imposed.

6.3 Storm Water Infiltration Systems
From a geotechnical perspective, allowing storm water to infiltrate the onsite soil in concentrated areas increases the potential for settlement, liquefaction, and water-related damage to structures/improvements, such as wet slabs or pumping subgrade, and should be avoided where possible. If infiltration systems

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are required on this site, care should be taken in designing systems that control the storm water as much as possible.

Preliminary infiltration testing was as part of Alta’s geotechnical investigation.

The resulting infiltration rates for P-1 and P-2 were 0.8 and 0.1-inches per hour, respectively. The results do not include a factor of safety.

The Project Geotechnical Consultant should review the final WQMP design prior to construction.

6.4 Boundary Conditions
Construction of retaining/screen walls along the site boundaries may require additional geotechnical recommendations concerning unsuitable soil removals and foundation design parameters. Boundary conditions for the project should be reviewed by the Project Geotechnical Consultant as the design progresses.

7.0 DESIGN CONSIDERATIONS

7.1 Structural Design
It is anticipated that multi-story wood-framed residential structures with slab ongrade and shallow foundations will be constructed. Upon the completion of rough grading, finish grade samples should be collected and tested in order to provide specific recommendations as they relate to the individual building pads.

These test results and corresponding design recommendations should be presented in a final rough grading report. Final slab and foundation design recommendations should be made based upon specific structure sitings, loading conditions, and as-graded soil conditions.

It is anticipated that the majority of onsite soils will possess “very low” to “low” expansion potential when tested in general accordance with ASTM Test Method D: 4829. For budgeting purposes, the following foundation design requirements for a range of potential expansion characteristics are presented.

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7.1.1 Foundation Design
Foundations may be preliminary designed based on the values presented in Table 7-1 below.

Table 7-1
Foundation Design Parameters*
Allowable Bearing 2000 lbs/ft2 (assuming a minimum embedment depth and width of 12 inches)
Lateral Bearing 250 lbs/ft2 at a depth of 12 inches plus 250 lbs/ft2 for each additional 12 inches of embedment to a maximum of 2000
lbs/ft2
.

Sliding Coefficient 0.30
Settlement Static Settlement – 0.5 inch in 40 feet
Dynamic Settlement – 0.5 inch in 40 feet
*These values may be increased as allowed by Code to resist transient loads such as wind or seismic. Building code and structural design considerations may govern depth and reinforcement requirements and should be evaluated.

7.1.1 Conventional Foundation Systems
Based on the onsite soils conditions and information supplied by the CBC 2022, conventional foundation systems may be designed in accordance with Tables 7-1 and 7-2.

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TABLE 7-2

CONVENTIONAL FOUNDATION DESIGN PARAMETERS
Expansion Potential Very Low to Low
Soil Category I
Design Plasticity Index 12
Minimum Footing
Embedment 12 inches*
*The minimum footing imbedments presented herein are based on expansion indexes. The structural engineer should determine minimum embedments based on the number of floors supported by the footings, the structural loading, and the requirements of the latest California Building Code.

Minimum Footing Width
12-inches-The structural engineer should determine the minimum footing width based on loading and the latest California Building Code.

Minimum Footing Reinforcement No. 4 rebar, one (1) on top, one (1) on bottom Minimum Slab Thickness 4 inches (actual)
Minimum Slab Reinforcement No. 3 rebar spaced 18 inches on center, each way Under-Slab Requirement See Section 7.2
Slab Subgrade Moisture Minimum of 110 percent of optimum moisture to a depth of 12 inches prior to placing concrete.

Footing Embedment Adjacent to
Swales and Slopes
If exterior footings adjacent to drainage swales are to exist within five (5) feet horizontally of the swale, the footing should be embedded sufficiently to assure embedment below the swale bottom is maintained. Footings adjacent to slopes should be embedded such that at least five- (5) feet is provided horizontally from edge of the footing to the face of the slope.

Garages
A grade beam reinforced continuously with the garage footings shall be constructed across the garage entrance, tying together the ends of the perimeter footings and between individual spread footings. This grade beam should be embedded at the same depth as the adjacent perimeter footings. A thickened slab, separated by a cold joint from the garage beam, should be provided at the garage entrance. Minimum dimensions of the thickened edge shall be six (6) inches deep. Footing depth, width and reinforcement should be the same as the structure. Slab thickness, reinforcement and under-slab treatment should be the same as the structure.

7.1.2 Post-Tensioned Slabs/Foundation Design Recommendations Post-tensioned slabs for the project may be designed utilizing the parameters presented in Tables 7-1 and 7-3. The parameters presented herein are based on methodology provided in the Design of PostTensioned Slabs-On-Ground, Third Edition, by the Post-Tensioning Institute, in accordance with the 2022 CBC.

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TABLE 7-3

POST-TENSION SLAB DESIGN PARAMETERS
Category Expansion Potential Minimum
Embedment*
Edge Lift Center Lift
Em (ft) Ym
(inch) Em (ft) Ym (inch)
I Very Low to Low 12 inches 5.4 0.61 9.0 0.26
Slab Subgrade Moisture
Category I Minimum 110% of optimum moisture to a depth of 12 inches prior to pouring concrete
Embedment*
The minimum footing embedments presented herein are based on expansion indexes. The structural engineer should determine minimum embedments based on the number of floors supported by the footings, the structural loading, and the requirements of the latest California Building Code. If mat slabs are utilized, alternate embedment depths can be provided.

Moisture Barrier
A moisture barrier should be provided in accordance with the recommendations presented in Section 7.2 The parameters presented herein are based on procedures presented in the Design of Post-Tensioned Slabs-OnGround, Third Edition. No corrections for vertical barriers at the edge of the slab, or for adjacent vegetation have been assumed. The design parameters are based on a Constant Suction Value of 3.9 pF.

7.2 Moisture Barrier
A moisture and vapor retarding system should be placed below the slabs-ongrade in portions of the structure considered to be moisture sensitive and should be capable of effectively preventing the migration of water and reducing the transmission of water vapor to acceptable levels. Historically, a 10-mil plastic membrane, such as Visqueen, placed between two to four inches of clean sand, has been used for this purpose. The use of this system or other systems can be considered, at the discretion of the designer, provided the system reduces the vapor transmission rates to acceptable levels.

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7.3 Seismic Design
The site classes were determined based on the referenced reports and published geologic maps in the area in general conformance with Chapter 20 of ASCE 7-16.

Based on the density of the underlying soils, a Site Class of C (shear wave velocity of 259 m/s) was selected. The seismic design parameters were calculated using a program based on the USGS website and ASCE 7-16 procedures. The resulting values are presented in Table 7-4.

TABLE 7-4 Seismic Ground Motion Values
2022 CBC and ASCE 7-16
Parameter Value
Site Class C
Site Latitude 33.8899
Site Longitude -117.8009
Spectral Response Acceleration Parameter, SS 1.845
Spectral Response Acceleration Parameter, S1 0.65
Site Coefficient, Fa 1.2
Site Coefficient, Fv 1.4
MCE Spectral Response Acceleration Parameter, SMS 2.215 MCE Spectral Response Acceleration Parameter, SM1 0.909 Design Spectral Response Acceleration Parameter, SDS 1.476 Design Spectral Response Acceleration Parameter, SD1 0.606 Peak Ground Acceleration, PGAM 0.95

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7.4 Block Walls
Block walls, if used, should be embedded a minimum of 2 feet below the lowest adjacent grade. Construction joints (not more than 20 feet apart) should be included in the block wall construction. Side yard walls should be structurally separated from the rear yard wall.

7.5 Footing Excavations
Soils from the footing excavations should not be placed in slab-on-grade areas unless properly compacted and tested. The excavations should be cleaned of all loose/sloughed materials and be neatly trimmed at the time of concrete placement.

7.6 Retaining Wall Design
Retaining walls should be founded on compacted fill and should be backfilled with granular soils that allow for drainage behind the wall. Foundations may be designed in accordance with the recommendations presented in Table 7-1, above. Unrestrained walls, free to rotate at least 0.001 radians, may be designed to resist lateral pressures imposed by a fluid with a unit weight determined in accordance with Table 7-5 below. The table also presents design parameters for restrained retaining walls. These parameters may be used to design retaining walls that may be considered as restrained due to the method of construction or location (corner sections of unrestrained retaining walls).

TABLE 7-5
Equivalent Fluid Pressures for 90% Compacted Fill
Backfill Active Pressure (psf/ft) At-Rest Pressure (psf/ft) Level 35 55

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Per the requirements of the CBC, the seismic force acting on the retaining walls with backfill exceeding 6-feet in height may be resolved utilizing the formula

19.5H2 lb/lineal ft (H=height of the wall). This force acts at approximately 0.6H above the base of the wall (inverted triangle). The seismic value can be converted as required by the retaining wall engineer. Retaining walls should be designed in general accordance with Section 1807A.2 of the 2022 CBC.  Restrained retaining walls should be designed for “at-rest” conditions, utilizing at-rest pressure.
 The design loads presented in the above table are to be applied on the retaining wall in a horizontal fashion and as such friction between wall and retained soils should not be allowed in the retaining wall analyses.  Additional allowances should be made in the retaining wall design to account for the influence of construction loads, temporary loads, and possible nearby structural footing loads.
 Select backfill should be granular, structural quality backfill with a Sand Equivalent of 20 or better and an ASCE Expansion Index of 20 or less. The backfill must encompass the full active wedge area. The upper one foot of backfill should be comprised of native on-site soils (see Plate A).  The wall design should include waterproofing (where appropriate) and backdrains or weep holes for relieving possible hydrostatic pressures. The backdrain should be comprised of a 4-inch perforated PVC pipe in a 1 ft. by 1 ft., ¾-inch gravel matrix, wrapped with a geofabric. The backdrain should be installed with a minimum gradient of 2 percent and should be outletted to an appropriate location.
 No backfill should be placed against concrete until minimum design strengths are achieved.

It should be noted that the allowable bearing and lateral bearing values presented in Table 7-1 are based on level conditions at the toe. Modified design parameters can be presented for retaining walls with sloping condition at the toe.

Other conditions should be evaluated on a case-by-case basis.

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RETAINING WALL BACKFILL DETAIL
NATIVE

BACKFILL
12 tN. MtN.
*OR AS MODIFIED

BY A SPECIFIC REPORT
DRAIN I.ATERALLY,

OR PROVIDE WEEP

HOLES AS REQUIRED

TO DMIN
PIPE: 4-INCH PERFORATED PVC, SCHEDULE 40, SDR35 OR APPROVED ALTERNATE MINIMUM 8 PERFORATIONS (1/4-IN. DIA.) PER LINEAL FT. IN BOTTOM HALF OF PIPE
ROCK: MINIMUM VOLUME OF 1 CU. FT. OF 3/4_IN. MAX. ROCK PER. LINEAL FOOT

OF PIPE, OR APPROVED ALTERNATE
FILTER FABRIC: MIRAFI 140 FILTER FABRIC OR APPROVED EQUIVALENT "64
ALTA cALTFoRNTA eEorEcl{NrcAL, tNc,
'vER, tTto PI-ATE A
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7.7 Exterior Slabs and Walkways
Exterior concrete slabs and walkways should be designed and constructed in consideration of the following recommendations.

7.7.1 Subgrade Compaction
The subgrade below exterior concrete slabs should be compacted to a minimum of 90 percent relative compaction as determined by ASTM Test Method: D 1557.

7.7.2 Subgrade Moisture
The subgrade below concrete slabs should be moisture conditioned to a minimum of 110 percent of optimum moisture prior to concrete placement.

7.7.3 Concrete Slab Thickness
Concrete flatwork and driveways should be designed utilizing four-inch minimum thickness.

7.7.4 Concrete Slab Reinforcement
Utilization of reinforcement for flatwork and driveways is subject to a cost/benefit analysis for the developer. Reinforcement will decrease the amount of cracking that may occur in flatwork, however, planning for occasional repairs may be more cost effective. Utilizing closely spaced control joints is likely more cost-effective than utilizing reinforcement.

The majority of the soils onsite are classified as medium to high in expansion potential. Consideration should be given to reinforcing flatwork with irregular (non-square/rectangular) shapes. Reinforcement may consist of 6x6 W.14/W1.4 welded wire mesh or an equivalent section of rebar.

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7.7.5 Control Joints
Weakened plane joints should be installed on walkways at intervals of approximately eight feet. Exterior slabs should be designed to withstand shrinkage of the concrete.

7.8 Concrete Design
As stated in Section 5.1.6, negligible concentrations of sulfates were detected in the onsite soils. Therefore, the use of sulfate resistant concrete is not required per ACI 318-14 at this time. Post-grading conditions should be evaluated, and final recommendations made at that time.

7.9 Corrosion
Based on preliminary testing from our investigation and the previous investigation, the onsite soils are classified as “non-corrosive” (Caltrans, 2022).

Consideration should be given to protecting buried metals from corrosion.

Typical measures may include using non-corrosive backfill, protective coatings, wrapping, plastic pipes, or a combination of these methods. A corrosion engineer should be consulted if specific design recommendations are required by the improvement designer.

Per ACI 318-14, an exposure class of C1 would be applicable to metals encased in concrete (rebar in footings) due to being exposed to moisture from surrounding soils. Per Table 19.3.2.1 of ACI 318-14, the requirements for concrete with an exposure class of C1 are a minimum compressive strength of 2500 psi and a maximum water-soluble chloride ion content in concrete of 0.30 (percent by weight of cement).

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7.10 Pavement Design
Pavement sections for the proposed streets shall be designed based on laboratory testing conducted on samples taken from the soil subgrade.

Preliminarily, based on an assumed R-Value of 30, the pavement may be designed utilizing the sections presented in Table 7-6. These sections should be verified upon the completion of grading, based on R-Value testing. The ultimate pavement section design for public streets is under the City of Yorba Linda’s purview.

Table 7-6
Preliminary Pavement Sections
Traffic
Index
Pavement Section Options
OR

5.0 3-inch AC on 6-inch AB 4-inch AC on 4-inch AB

5.5 3-inch AC on 7-inch AB 4-inch AC on 5-inch AB

6.0 3.5-inch AC on 7.5-inch AB 4.5-inch AC on 6.5-inch AB AC-Asphalt Concrete
AB-Caltrans Class II Base
Construction of the streets should be accomplished in accordance with the current criteria of the City of Yorba Linda. Prior to the placement of base material, the subgrade should be suitably moisture conditioned, processed and compacted to a minimum 95 percent of the laboratory maximum density (ASTM:

D 1557) to at least twelve (12) inches below subgrade. After subgrade compaction, the exposed grade should then be "proof"-rolled with heavy equipment to ensure the grade does not "pump" and is verified as non-yielding.

Aggregate base material should be placed on the compacted subgrade and compacted in-place to a minimum 95 percent of the laboratory standard obtained per ASTM: D 1557.

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7.11 Site Drainage
Positive drainage away from the proposed structures should be provided and maintained. Roof, pad, and lot drainage should be collected and directed away from the structures toward approved disposal areas through drainage terraces, gutters, down drains, and other devices. Design fine grade elevations should be maintained through the life of the structure or if design fine grade elevations are altered, adequate area drains should be installed in order to provide rapid discharge of water, away from structures.

8.0 LOT MAINTENANCE
Ongoing maintenance of the improvements is essential to the long-term performance of structures and slopes. As such, the owners must implement certain maintenance procedures. The attached "Maintenance and Improvement Considerations" presented in Appendix D should be reviewed for issues related to drainage, slopes, maintenance, backyard improvements, etc. The following recommendations should also be implemented.

8.1 Lot Drainage
Roof, pad and lot drainage should be collected and directed away from structures and slopes and toward approved disposal areas. Design fine grade elevations should be maintained throughout the life of the structure or if design fine grade elevations are altered, adequate area drains should be installed in order to provide rapid discharge of water, away from structures and slopes.

Residents should be made aware that they are responsible for maintenance and cleaning of all drainage terraces, down drains, and other devices that have been installed to promote structure and slope stability.

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8.2 Burrowing Animals
Residents or owners should undertake a program for the elimination of burrowing animals. This should be an ongoing program in order to maintain slope stability.

9.0 FUTURE PLAN REVIEWS
This report represents a geotechnical review of the tract map. As the project design progresses, site specific geologic and geotechnical issues need to be considered in the design and construction of the project. Consequently, future plan reviews may be necessary. These reviews may include reviews of:
 Grading Plans
 Foundation plans
 Utility Plans
These plans should be forwarded to the Project Geotechnical Consultant for review.

10.0 CLOSURE

10.1 Geotechnical Review
For the purposes of this report, multiple working hypotheses were established for the project, utilizing the available data and the most probable model is used for the analysis. Future information collected during the proposed grading operations is intended to evaluate the hypothesis and as such, some of the assumptions summarized in this report may need to be changed. Some modifications of the grading recommendations may become necessary, should the conditions encountered in the field differ from the conditions hypothesized in this report.

Plans and sections of the project specifications should be reviewed by Alta, to evaluate conformance with the intent of the recommendations contained in this report. If the project description or final design varies from that described in

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herein, Alta must be consulted regarding the applicability of the recommendations contained herein and whether any changes are required. Alta accepts no liability for any use of its recommendations if the project description or final design varies and Alta is not consulted regarding the alterations.

10.2 Limitations
This report is based on the following: 1) the project as presented on the attached plan; 2) the information obtained from the subsurface investigation at the approximate locations indicated on the plans included herein; and 3) from the information presented in the referenced reports. The findings and recommendations are based on the results of the subsurface investigation, laboratory testing, and office analysis combined with an interpolation and extrapolation of conditions between and beyond the subsurface excavation locations. However, the materials adjacent to or beneath those observed may have different characteristics than those observed, and no precise representations are made as to the quality or extent of the materials not observed. The results reflect an interpretation of the direct evidence obtained.

Work performed by Alta has been conducted in a manner consistent with the level of care and skill ordinarily exercised by members of the geotechnical profession currently practicing in the same locality under similar conditions. No other representation, either expressed or implied, and no warranty or guarantee is included or intended.

The recommendations presented in this report are based on the assumption that an appropriate level of field review will be provided by a geotechnical consultant who is familiar with the design and site geologic conditions. That field review shall be sufficient to confirm that geotechnical and geologic conditions exposed during grading are consistent with the geologic representations and corresponding recommendations presented in this report.

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The conclusions and recommendations included in this report are applicable to the specific design of this project as discussed in this report. They have no applicability to any other project or to any other location and any and all subsequent users accept any and all liability resulting from any use or reuse of the data, opinions, and recommendations without the prior written consent of Alta.

Alta has no responsibility for construction means, methods, techniques, sequences, procedures, safety precautions, programs in connection with the construction, acts or omissions of the CONTRACTOR or any other person performing any of the construction, or for the failure of any of them to carry out the construction in accordance with the final design drawings and specifications

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APPENDIX A

REFERENCES

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APPENDIX A
Selected References
California Code of Regulations, 2022, California Building Code, Title 24, Part 2, Volume 2, Based on the 2021 International Building Code, Effective Date January 1, 2023.

California Department of Water Resources, Water Data Library, 2022, Website, http://www.wdl.water.ca.gove/waterdatalibrary/
California Division of Mines and Geology, 2008, Guidelines for evaluating and mitigating seismic hazards in California: Department of Conservation, Special Publication 117a.

California Geological Survey, 1999, Earthquake Fault Zones, A Guide for Government Agencies, Property Owners/Developers, And Geoscience Practitioners for Assessing Fault Rupture Hazards in California, Special Publication 42, Revised 1999.

California State Water Resources Control Board, Geotracker, 2024, Website, https://geotracker.waterboards.ca.gov/
Dibble, 2001, Geologic Map of the Whittier and La Habra quadrangles, Western Puente Hills, Los Angeles and Orange Counties, California.

Historical Aerials.com, 2024, online vertical and color aerials photographs from 1946 through 2022, viewed January 2025, http://www.historicaerials.com/ Jennings, C.W., and Bryant, W.A., 2010, Fault Activity Map of California: California Geological Survey Geologic Data Map No. 6, map scale 1:750,000.

Jennings, C. W., and Bryant, W. A., 2021, An explanatory test to accompany the Fault Activity Map of California: California Department of Conservation, California Geological Survey.

Jennings, C. W., 1985, An explanatory text to accompany the 1:750,000 scale fault and geologic map of California: California Division of Mines and Geology, Bulletin 201, 197p.

Romanoff, Melvin, 1989, Underground Corrosion, NBS Circular 579, Reprinted by NACE, Houston, TX, 1989.

U.S. Geological Survey, 2008, National Seismic Hazards Maps – Source Parameters, http://geohazards.usgs.gov/cfusion/hazfaults_2008_search/query_main.cfm.

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APPENDIX B
Subsurface Investigation

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APPENDIX B
Subsurface Investigation
Alta's subsurface investigation consisted of excavating, logging, and sampling five (5) hollowstem auger borings. In addition, two shallow borings were advanced for preliminary infiltration testing. Details of the subsurface investigation are presented in Table B-1. The approximate locations of the exploratory excavations are shown on the accompanying Plate 1 and the Geotechnical Logs are attached.

TABLE B-1

SURFACE INVESTIGATION DETAILS
Equipment Range of
Depths
Sampling Methods Sample Locations
8” HollowStem Auger Up to 51.0
feet

1. Bulk Samples

2. Ring Samples

1. Bulk-Select Depths

2. Ring-Every 2.5 or 5.0 feet.

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UNIFIED SOI L CLASSIFIICATION SYSTEM
Major Divisions lfl tr Description Major Divisions an tr Coarse
Grained
Soils
N4ore than
50%
retained on
No 200
steve
Gravel
and
Sravelly
Soils
han 50%
frachon
relained
on No, 4
'l
ts
*
,-l*
EIF
GW
Well-graded grcvels or gravel sand
mixtures, little or no fines
Fine
(lrained
isoils
l\lore than
Silts
And
Clays
LL,<50
n
ML
Inorganic silts and very fine sands,
rock flour, silty or clayey fine sands
or clavev silts with slioht olasticitv
GP
Poorly-graded gravels or gravel
sand mixture, little or no fines CL
Inorganic clays of low to medium
plasticity, gravelly clays, sandy
clays, silty clays, lean clays Silty gravels, gravel-sand-silt mixtures
OL
Organic silts and organic silt-clays
of low plasticity
Clayey gravels, gravel-sand-clay
mixtures
Silts
And
Clays
LL,<50
MF
Inorganic silts, micaceous or
diatomaceous fine or silty soils,
elastic silts Sand
and
Sandy
Soils
than 50%
fraclion
Passes
on No, 4
i'+.
3_'. JV!
Well-graded sands or gravelly
sands, little or no fines
on No 200
steve VH
Inorganic clays of high plasticity,
fat clays SP
Poorly-graded sands or gravelly
sands, little or no fines
SM Silty sands, sarrd-silt mixtures OF
Organic clays of medium to high
plasticity
sc Clayey sands, and-clay mixtures Highly Organic
Soils PT Peat and other highly organic soils
BoUNDARY CLASSIFICATIoN: Soils possessing characteristics of two groups are designated by combinations of group symbols PARTICLE SIZ:E LIMITS
U.S. STANDA,RD SiERIES SIEVE
200 40 10 4

CLEAR SQUARE SIEVE OPENINGS
3t4" 3,, ,t2"

LABORATORY TESTS
Symbol Tesl
DS
DSR
cc)N
SA
MAX
RV
EI
SE
AL
CHEM
HY
Direct Shear
Direct Shear
(Remolded)
Sieve Analysis
Maximum Density
Resistance (R) Value
Expansion Index
Sand Equivalent
Atterberg Limits
Chemical Analysis
Hydrometer Analysis

SOIL MOISTURE

SIZE PROPORTIONS
Trace - <5%
Few-5to10%
Some - 15 to 25%
Increasing \/isual Moisture Content
Silts
an0
Clays
Sand Gravel
Cobbles Boulders
Fine Medium Coarsi€r Fine Coarse

RELATIVE DENSITY
Sands and Gravels Blows/Foot (SPT)
Very Loose
Loose
Medium Dense
Dense
Very Dense
<4
4-10
11-30
31 -50
>50

CON SI STENCY C IASSI FI CATI ON
Silts and Clays Criteria
Very Soft
Soft
Firm
stiff
Very Stiff
Thumb penetrates soil >1 in.

Thumb penetrates soil 1 in,
Thumb penetrates soil 1/4 in
Readily indented with thumbnail
Thumbnail will not indent soil

HARDNESS
KEY TO EXPLORATORY BORING LOGS}
,n
/L>//J, ALTA CALIFORNTA GEOTECHNTCAL tNC.
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APPENDIX C
Laboratory Testing

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LABORATORY TESTING
The following laboratory tests were performed on representative samples in accordance with the applicable latest standards or methods from the ASTM, California Building Code (CBC) and California Department of Transportation.

Classification
Soils were classified with respect to the Unified Soil Classification System (USCS) in accordance with ASTM D-2487 and D-2488.

Particle Size Analysis
Modified hydrometer testing was conducted to aid in classification of the soil. The results of the particle size analysis are presented in Table 7-1 and Table C.

Maximum Density/Optimum Moisture
The maximum dry density and optimum moisture content of one (1) representative bulk sample was evaluated in accordance with ASTM D-1557. The results are summarized in Table C.

Expansion Index Tests
One (1) expansion index test was performed to evaluate the expansion potential of typical onsite soil. Testing was carried out in general conformance with ASTM Test Method D-4829. The results are presented in Table C.

Consolidation Tests
Consolidation testing was performed on two (2) relatively “undisturbed” soil sample at their natural moisture content in accordance with procedures outlined in ASTM D-2435. The samples were placed in a consolidometer and loads were applied incrementally in geometric progression. The samples (2.42-inches in diameter and 1-inch in height) were permitted to consolidate under each load increment until the slope of the characteristic linear secondary compression portion of the thickness versus log of time plot was apparent. The percent consolidation for each load cycle was recorded as the ratio of the amount of vertical

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compression to the original 1-inch height. The consolidation test results are shown on Plate C1.

Chemical Analyses
Chemical testing was performed on one select sample. The results of this test (sulfate content, resistivity, chloride content and pH) is presented on Table C.

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APPENDIX D
Maintenance and Improvement Considerations

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MAINTENANCE AND IMPROVEMENT CONSIDERATIONS
General
Owners purchasing property must assume a certain degree of responsibility for improvements and for maintaining conditions around their home. Of primary importance from a geotechnical standpoint are maintaining drainage patterns and minimizing the soil moisture variation below all improvements. Such design, construction and owner maintenance provisions may include:
 Employing contractors for improvements who design and build in recognition of local building codes and specific site soils conditions.
 Establishing and maintaining positive drainage away from all foundations, walkways, driveways, patios, and other improvements.
 Avoiding the construction of planters adjacent to structural improvements.

Alternatively, planter sides/bottoms can be sealed with an impermeable membrane and drained away from the improvements via subdrains into approved disposal areas.  Sealing and maintaining construction/control joints within concrete slabs and walkways to reduce the potential for moisture infiltration into the subgrade soils.  Utilizing landscaping schemes with vegetation that requires minimal watering. Watering should be done in a uniform manner, as equally as possible on all sides of the foundation, keeping the soil "moist" but not allowing the soil to become saturated.  Maintaining positive drainage away from structures and providing roof gutters on all structures with downspouts that are designed to carry roof runoff directly into area drains or discharged well away from the foundation areas.  Avoiding the placement of trees closer to the proposed structures than a distance of one-half the mature height of the tree.
 Observation of the soil conditions around the perimeter of the structure during extremely hot/dry or unusually wet weather conditions so that modifications can be made in irrigation programs to maintain relatively uniform moisture conditions.

Sulfates
Owners should be cautioned against the import and use of certain inorganic fertilizers, soil amendments, and/or other soils from offsite sources in the absence of specific information relating to their chemical composition. Some fertilizers have been known to leach sulfate compounds into soils and increase the sulfate concentrations to potentially detrimental levels.

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Site Drainage
 The owners should be made aware of the potential problems that may develop when drainage is altered through construction of hardscape improvements. Ponded water, drainage over the slope face, leaking irrigation systems, overwatering, or other conditions which could lead to ground saturation must be avoided.  No water should be allowed to flow over the slopes. No alteration of pad gradients should be allowed that would prevent pad and roof runoff from being directed to approved disposal areas.
 Drainage patterns have been established at the time of the fine grading should be maintained throughout the life of the structure. No alterations to these drainage patterns should be made unless designed by qualified professionals in compliance with local code requirements and site-specific soils conditions.

Slope Drainage
 Residents should be made aware of the importance of maintaining and cleaning all interceptor ditches, drainage terraces, down drains, and any other drainage devices, which have been installed to promote slope stability.
 Subsurface drainage pipe outlets may protrude through slope surfaces and/or wall faces. These pipes, in conjunction with the graded features, are essential to slope and wall stability and must be protected in-place. They should not be altered or damaged in any way.

Planting and Irrigation of Slopes
 Seeding and planting of the slopes should be planned to achieve, as rapidly as possible, a well-established and deep-rooted vegetal cover requiring minimal watering.  It is the responsibility of the landscape architect to provide such plants initially and of the residents to maintain such planting. Alteration of such a planting scheme is at the resident's risk.
 The resident is responsible for proper irrigation and for maintenance and repair of properly installed irrigation systems. Leaks should be fixed immediately.  Sprinklers should be adjusted to provide maximum uniform coverage with a minimum of water usage and overlap. Overwatering with consequent wasteful runoff and serious ground saturation must be avoided.
 If automatic sprinkler systems are installed, their use must be adjusted to account for seasonal and natural rainfall conditions.

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Burrowing Animals
 Residents must undertake a program to eliminate burrowing animals. This must be an ongoing program in order to promote slope stability.

Owner Improvement
Owner improvements (pools, spas, patio slabs, retaining walls, planters, etc.) should be designed to account for the terrain of the project, as well as expansive soil conditions and chemical characteristics. Design considerations on any given lot may need to include provisions for differential bearing materials, ascending/descending slope conditions, bedrock structure, perched (irrigation) water, special geologic surcharge loading conditions, expansive soil stresses, and long-term creep/settlement.

All owner improvements should be designed and constructed by qualified professionals utilizing appropriate design methodologies, which account for the on-site soils and geologic conditions.

Each lot and proposed improvement should be evaluated on an individual basis.

Setback Zones
Manufactured slopes may be subject to long-term settlement and creep that can manifest itself in the form of both horizontal and vertical movement. These movements typically are produced as a result of weathering, erosion, gravity forces, and other natural phenomenon. A setback adjacent to slopes is required by most building codes, including the California Building Code. This zone is intended to locate and support the residential structures away from these slopes and onto soils that are not subject to the potential adverse effects of these natural phenomena.

The owner may wish to construct patios, walls, walkways, planters, swimming pools, spas, etc. within this zone. Such facilities may be sensitive to settlement and creep and should not be constructed within the setback zone unless properly engineered. It is suggested that plans for such improvements be designed by a professional engineer who is familiar with grading ordinances and design and construction requirements. In addition, we recommend that the

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designer and contractor familiarize themselves with the site specific geologic and geotechnical conditions on the specific lot.

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APPENDIX E
Earthwork Specifications

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Legend
Approximate Location of Hollow Stem Auger Boring
Approximate Location of Infiltration Test
200 ft
N
➤

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Attachment F : Hydrology Calculations

Educational Materials

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Never allow pollutants to enter the
The Ocean Begins at Your Front Door
Follow these simple steps to help reduce water
pollution:

Household Activities
Do not rinse spills with water. Use dry cleanup
methods such as applying cat litter or another
absorbent material, sweep and dispose of in
the trash. Take items such as used or excess
batteries, oven cleaners, automotive fluids,
painting products and cathode ray tubes, like
TVs and computer monitors, to a Household
Hazardous Waste Collection Center (HHWCC).

For a HHWCC near you call (714) 834-6752 or
visit www.oclandfills.com.

Do not hose down your driveway, sidewalk or
patio to the street, gutter or storm drain. Sweep
up debris and dispose of it in the trash.

Automotive
Take your vehicle to a commercial car
wash whenever possible. If you wash your
vehicle at home, choose soaps, cleaners, or
detergents labeled non-toxic, phosphate- free
or biodegradable. Vegetable and citrus-based
products are typically safest for the environment.

Do not allow washwater from vehicle washing
to drain into the street, gutter or storm drain.

Excess washwater should be disposed of in the
sanitary sewer (through a sink or toilet) or onto
an absorbent surface like your lawn.

Monitor your vehicles for leaks and place a pan
under leaks. Keep your vehicles well maintained
to stop and prevent leaks.

Never pour oil or antifreeze in the street, gutter
or storm drain. Recycle these substances at a
service station, a waste oil collection center or
used oil recycling center. For the nearest Used
Oil Collection Center call 1-800-CLEANUP or
visit www.1800cleanup.org.
street, gutter or storm drain!
Lawn and Garden
Pet and animal waste
Pesticides
Clippings, leaves and soil
Fertilizer
Common Pollutants
Automobile
Oil and grease
Radiator fluids and antifreeze
Cleaning chemicals
Brake pad dust
Home Maintenance
Detergents, cleaners and solvents
Oil and latex paint
Swimming pool chemicals
Outdoor trash and litter
Trash
Place trash and litter that cannot be recycled in
securely covered trash cans.

Whenever possible, buy recycled products.

Remember: Reduce, Reuse, Recycle.

Pet Care
Always pick up after your pet. Flush waste down
the toilet or dispose of it in the trash. Pet waste,
if left outdoors, can wash into the street, gutter
or storm drain.

If possible, bathe your pets indoors. If you must
bathe your pet outside, wash it on your lawn or
another absorbent/permeable surface to keep
the washwater from entering the street, gutter or
storm drain.

Follow directions for use of pet care products
and dispose of any unused products at a
HHWCC.

Pool Maintenance
Pool and spa water must be dechlorinated and free
of excess acid, alkali or color to be allowed in the
street, gutter or storm drain.

When it is not raining, drain dechlorinated pool and
spa water directly into the
sanitary sewer.

Some cities may have ordinances that do not allow
pool water to be disposed of in the storm drain.

Check with your city.

Landscape and Gardening
Do not over-water. Water your lawn and garden by
hand to control the amount of water you use or set
irrigation systems to reflect seasonal water needs.

If water flows off your yard onto your driveway or
sidewalk, your system is over-watering. Periodically
inspect and fix leaks and misdirected sprinklers.

Do not rake or blow leaves, clippings or pruning
waste into the street, gutter or storm drain. Instead,
dispose of waste by composting, hauling it to a
permitted landfill, or as green waste through your
city’s recycling program.

Follow directions on pesticides and fertilizer,
(measure, do not estimate amounts) and do not use
if rain is predicted within 48 hours.

Take unwanted pesticides to a HHWCC to be
recycled. For locations and hours of HHWCC, call
(714) 834-6752 or visit www.oclandfills.com.

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Did You Know?
Most people believe that the largest source
of water pollution in urban areas comes from
specific sources such as factories and sewage
treatment plants. In fact, the largest source
of water pollution comes from city streets,
neighborhoods, construction sites and parking
lots. This type of pollution is sometimes
called “non-point source” pollution.

There are two types of non-point source
pollution: stormwater and urban runoff
pollution.

Stormwater runoff results from rainfall.

When rainstorms cause large volumes
of water to rinse the urban landscape,
picking up pollutants along the way.

Urban runoff can happen any time of
the year when excessive water use from
irrigation, vehicle washing and other
sources carries trash, lawn clippings and
other urban pollutants into storm drains.

Where Does It Go?
Anything we use outside homes, vehicles and
businesses – like motor oil, paint, pesticides,
fertilizers and cleaners – can be blown or washed
into storm drains.

A little water from a garden hose or rain can also
send materials into storm drains.

Storm drains are separate from our sanitary
sewer systems; unlike water in sanitary sewers
(from sinks or toilets), water in storm drains is
not treated before entering our waterways.

Even if you live miles from the Pacific
Ocean, you may be unknowingly
polluting it.

Sources of Non-Point Source Pollution
Automotive leaks and spills.

Improper disposal of used oil and other engine
fluids.

Metals found in vehicle exhaust, weathered paint,
rust, metal plating and tires.

Pesticides and fertilizers from lawns, gardens and
farms.

Improper disposal of cleaners, paint and paint
removers.

Soil erosion and dust debris from landscape and
construction activities.

Litter, lawn clippings, animal waste, and other
organic matter.

Oil stains on parking lots and paved surfaces.

The Effect on the Ocean
Non-point source
pollution can have
a serious impact
on water quality
in Orange County.

Pollutants from the
storm drain system
can harm marine life
as well as coastal and wetland habitats. They can
also degrade recreation areas such as beaches,
harbors and bays.

Stormwater quality management programs have
been developed throughout Orange County to
educate and encourage the public to protect water
quality, monitor runoff in the storm drain system,
investigate illegal dumping and maintain storm
drains.

Support from Orange County residents and
businesses is needed to improve water quality
and reduce urban runoff pollution. Proper use
and disposal of materials will help stop pollution
before it reaches the storm drain and the ocean.

Dumping one quart of motor oil into a
storm drain can contaminate 250,000
gallons of water.

Page 1603 of 2028 ends

For More Information
Aliso Viejo (949) 425-2535
Anaheim Public Works Operations (714) 765-6860
Brea Engineering (714) 990-7666
Buena Park Public Works . . . . . . . . . . . . (714) 562-3655 Costa Mesa Public Services (714) 754-5323
Cypress Public Works (714) 229-6740
Dana Point Public Works (949) 248-3584
Fountain Valley Public Works . . . . . . . . . . (714) 593-4441 Fullerton Engineering Dept. (714) 738-6853
Garden Grove Public Works (714) 741-5956
Huntington Beach Public Works . . . . . . . . (714) 536-5431 Irvine Public Works (949) 724-6315
La Habra Public Services (562) 905-9792
La Palma Public Works (714) 690-3310
Laguna Beach Water Quality (949) 497-0378
Laguna Hills Public Services (949) 707-2650
Laguna Niguel Public Works . . . . . . . . . . (949) 362-4337 Laguna Woods Public Works (949) 639-0500
Lake Forest Public Works . . . . . . . . . . . . (949) 461-3480 Los Alamitos Community Dev. (562) 431-3538
Mission Viejo Public Works (949) 470-3056
Newport Beach, Code & Water
Quality Enforcement (949) 644-3215
Orange Public Works (714) 532-6480
Placentia Public Works (714) 993-8245
Rancho Santa Margarita (949) 635-1800
San Clemente Environmental Programs . . . . (949) 361-6143 San Juan Capistrano Engineering (949) 234-4413
Santa Ana Public Works . . . . . . . . . . . . . (714) 647-3380 Seal Beach Engineering . . . . . . . . . . . . .(562) 431-2527 x317 Stanton Public Works (714) 379-9222 x204
Tustin Public Works/Engineering (714) 573-3150
Villa Park Engineering (714) 998-1500
Westminster Public Works/Engineering . . . .(714) 898-3311 x446 Yorba Linda Engineering . . . . . . . . . . . . (714) 961-7138 Orange County Stormwater Program (877) 897-7455
Orange County 24-Hour
Water Pollution Problem Reporting Hotline
1-877-89-SPILL (1-877-897-7455)
On-line Water Pollution Problem Reporting Form
w w w.o c w a t e r s h e d s.c o m
The Ocean Begins
at Your Front Door
California Environmental Protection Agency
www.calepa.ca.gov
• Air Resources Board
www.arb.ca.gov
• Department of Pesticide Regulation
www.cdpr.ca.gov
• Department of Toxic Substances Control
www.dtsc.ca.gov
• Integrated Waste Management Board
www.ciwmb.ca.gov
• Office of Environmental Health Hazard
Assessment
www.oehha.ca.gov
• State Water Resources Control Board
www.waterboards.ca.gov
Earth 911 - Community-Specific Environmental
Information 1-800-cleanup or visit www.1800cleanup.
org
Health Care Agency’s Ocean and Bay Water Closure
and Posting Hotline
(714) 433-6400 or visit www.ocbeachinfo.com
Integrated Waste Management Dept. of Orange
County (714) 834-6752 or visit www.oclandfills.com for
information on household hazardous waste collection
centers, recycling centers and solid waste collection
O.C. Agriculture Commissioner
(714) 447-7100 or visit www.ocagcomm.com
Stormwater Best Management Practice Handbook
Visit www.cabmphandbooks.com
UC Master Gardener Hotline
(714) 708-1646 or visit www.uccemg.com
Printed on Recycled Paper
The Orange County Stormwater Program has created
and moderates an electronic mailing list to facilitate
communications, take questions and exchange ideas among its users about issues and topics related to stormwater and urban runoff and the implementation of program elements.

To join the list, please send an email to
[email protected]
Orange County Stormwater Program

Page 1604 of 2028 ends

Pet Waste
• Pollution: Pet waste carries bacteria through
our watersheds and eventually will be washed
out to the ocean. This can posea health risk to
swimmers and surfers.
• Solution: Pick up after your pets!
Trash and Debris
• Pollution: Trash and debris
can enter waterways by
wind, littering and careless
maintenance of trash
receptacles. Street sweeping
collects some of this trash;
however, much of what isn’t
captured ends up in our storm
drain system where it flows untreated out to the
ocean.
• Solution: Don’t litter and make sure trash
containers are properly covered. It is far more
expensive to clean up the litter and trash that ends
up in our waterways than it is to prevent it in the
first place. Come out to one of Orange County’s
many locations for Coastal and Inner-Coastal
Cleanup Day, which is held in September.

Motor Oil / Vehicle Fluids
• Pollution: Oil and petroleum products from our
vehicles are toxic to people, wildlife and plants.
• Solution: Fix any leaks
from your vehicle and
keep the maintenance
up on your car. Use
absorbent material such
as cat litter on oil spills,
then sweep it up and
dispose of it in the trash.

Recycle used motor oil
ata local Household Hazardous Waste Collection
Center.

Low Impact Development, Water Conservation
& Pollution Prevention
The Ocean Begins at Your Front Door
DID YOU KNOW?
Homeowners Guide
for Sustainable Water Use

A TEAM EFFORT
The Orange County Stormwater Program has teamed with the Municipal Water District of Orange County (MWDOC) and the University of California Cooperative Extension Program (UCCE) to develop this pamphlet.

Low Impact Development (LID) and sustainable water use prevents water pollution and conserves water for drinking and reuse. Reducing your water use and the amount of water flowing from your home protects the environment and saves you money.

Thank you for making water protection
a priority!
For more information,
please visit
www.ocwatersheds.
com/publiced/
www.mwdoc.com
www.uccemg.com
Pesticides and Fertilizer
• Pollution: The same pesticides
that are designed to be toxic to
pests can have an equally lethal
impact on our marine life. The
same fertilizer that promotes plant
growth in lawns and gardens
can also create nuisance algae
blooms, which remove oxygen
from the water and clog waterways
when it decomposes.
• Solution: Never use pesticides or fertilizer within 48 hours of an anticipated rainstorm. Use only as much
as is directed on the label and keep it off driveways and sidewalks.

Dirt and Sediment
• Pollution: Dirt or sediment can impede the flow of the stormwater and negatively impact stream habitat as it
travels through waterways and deposits downstream.

Pollutants can attach to sediment, which can then be
transported through our waterways.
• Solution: Protect dirt stockpiles by covering them with tarps or secure plastic sheets to prevent wind or rain from allowing dirt or sediment to enter the storm drain system.

Metals
• Pollution: Metals and other toxins present in car wash water can harm important plankton, which forms the base of the aquatic food chain.
• Solution: Take your car toa commercial car wash
where the wash water is captured and treated ata local
wastewater treatment plant.

The Pollution Solution
Several residential activities can result in water pollution. Among these activities are car washing and hosing off driveways and sidewalks. Both activities can waste water and result in excess runoff. Water conservation methods described in this pamphlet can prevent considerable amounts of runoff and conserve water. By taking your car toa commercial car wash and by sweeping driveways and sidewalks, you can further prevent the transport of pollutants to Orange County waterways. Here are some of the common pollutants for which you can be part of the solution:

To report a spill, call the Orange County 24-Hour Water Pollution Prevention Reporting Hotline
at 1-877-89-SPILL \ (1-877-897-7455)
Special Thanks to
The City of Los Angeles Stormwater Program for the use of its artwork The Metropolitan Water District of Southern California for the use of the CaliforniaFriendly Plant and Native Habitat photos Did you know that most of the pollution found in our waterways is not from a single source, but from a “nonpoint” source meaning the accumulation of pollution from residents and businesses throughout the community

Page 1605 of 2028 ends

Options for Rainwater
Harvesting and Reuse
Rainwater harvesting is a great way to save
money, prevent pollution and reduce potable
water use. To harvest your rainwater, simply
redirect the runoff from roofs and downspouts to rain barrels.

Rain gardens are another option; these reduce runoff as well as encourage infiltration.

Downspout
Disconnection/Redirection
Disconnecting downspouts
from pipes running to the gutter
prevents runoff from transporting
pollutants to the storm drain.

Once disconnected, downspouts
can be redirected to rain gardens
or other vegetated areas, or be
connected to a rain barrel.

Rain Barrels
Rain barrels capture rainwater
flow from roofs for reuse in
landscape irrigation. Capacity
of rain barrels needed for your
home will depend on the amount
of roof area and rainfall received.

When purchasing your rain barrel,
make sure it includes a screen, a
spigot to siphon water for use, an
overflow tube to allow for excess
water to run out and a connector if
you wish to connect multiple barrels to add capacity of water storage.

Mosquito growth prevention is very important when installing a rain barrel.The best way to prevent mosquito breeding is to eliminate entry points by ensuring all openings are sealed tightly. If these methods are unsuccessful, products are available to kill mosquito larvae, but that are harmless to animals and humans. Regular application of these products is essential.Please visit the Orange County Vector Control website for more information at
www.ocvcd.org/mosquitoes3.php.

Rain Gardens
Rain gardens allow runoff to be directed from your roof downspout into a landscaped area. Vegetation and rocks in the garden will slow the flow of water to allow for infiltration into the soil. Plants and soil particles will absorb pollutants from the roof runoff. By utilizing a native plant palate, rain gardens can be maintained all year with minimal additional irrigation.

These plants are adapted to the semi-arid climate of Southern California, require less water and can reduce your water bill.

Before modifying your yard to install a rain
garden, please consult your local building and/or
planning departments to ensure your garden plan
follows pertinent building codes and ordinances.

Besides codes and ordinances, some home
owner associations also have guidelines for yard
modifications. If your property is in hill areas
or includes engineered slopes, please seek
professional advice before proceeding
with changes.

R unoff , R ainwater and R euse
For information on how to disconnect a
downspout or to install and maintain a
rain barrel or rain garden at your home,
please see the Los Angeles Rainwater
Harvesting Program, A Homeowner’s
“How-To” Guide, November 2009 at
www.larainwaterharvesting.org/
Water runoff from sprinklers left
on too long will carry pollutants
into our waterways.

Permeable pavement allows water runoff to
infiltrate through the soil and prevents most
pollutants from reaching the storm drain system.

What is Low Impact Development (LID)?
Low Impact Development (LID) is a method of development that seeks to maintain the natural hydrologic character of an area. LID provides a more sustainable and pollution-preventative approach to water management.

New water quality regulations require implementation of LID in larger new developments and encourage implementation of LID and other sustainable practices in existing residential areas.

Implementing modifications to your lawn or garden can reduce pollution in our environment, conserve water and reduce your water bill.

Where Does Water Runoff Go?
Stormwater, or water from rainfall events, and runoff from outdoor water use such as sprinklers and hoses flows from homes directly into catch basins and the storm drain system. After entering the storm drain, the water flows untreated into streams, rivers, bays and ultimately the Pacific Ocean. Runoff can come from lawns, gardens, driveways, sidewalks and roofs. As it flows over hard, impervious surfaces, it picks up pollutants.

Some pollutants carried by the water runoff include trash, pet waste, pesticides, fertilizer, motor oil and more.

Water Conservation
Pollution not only impairs the water quality for habitat and recreation, it can also reduce the water available for reuse. Runoff allowed to soak into the ground is cleaned as it percolates through the soil, replenishing depleted groundwater supplies. Groundwater provides at least 50% of the total water for drinking and other indoor household activities in north and central Orange County. When land is covered with roads, parking lots, homes, etc., there is less land to take in the water and more hard surfaces over which the water can flow.

In Orange County, 60-70% of water used by residents and businesses goes to irrigation and other outdoor uses. Reusing rainwater to irrigate our lawn not only reduces the impact of water pollution from runoff, but it also is a great way to conserve our precious water resources and replenish our groundwater basin.

Permeable pavement allows water
runoff to infiltrate through the soil
and prevents most pollutants from
reaching the storm drain system.

Other Water Conservation and
Pollution Prevention Techniques
Native Vegetation and Maintenance
“California Friendly” plants or native vegetation can significantly reduce water use. These plants often require far less fertilizers and pesticides, which are two significant pollutants found in Orange County waterways. Replacing water “thirsty” plants and grass types with water efficient natives is a great way to save water and reduce the need for potentially harmful pesticides and fertilizer.

Please see the California Friendly Garden Guide produced by the Metropolitan Water District of Southern California and associated Southern California Water Agencies for a catalog of California friendly plants and other garden resources at
www.bewaterwise.com/Gardensoft.

Weed Free Yards
Weeds are water thieves.

They often reproduce quickly
and rob your yard of both
water and nutrients. Weed
your yard by hand if possible.

If you use herbicides to
control the weeds, use only
the amount recommended on
the label and never use it if
rain is forecast within the next
48 hours.

Soil Amendments
Soil amendments such as green waste (e.g. grass clippings, compost, etc.) can be a significant source of nutrients and can help keep the soil near the roots of plants moist. However, they can cause algal booms if they get into our waterways, which reduces the amount of oxygen in the water and impacts most aquatic organisms. It is important to apply soil amendments more than 48 hours prior to predicted rainfall.

IRRIGATE

EFFICIENTLY
Smart Irrigation
Controllers
Smart Irrigation Controllers have
internal clocks as well as sensors
that will turn off the sprinklers
in response to environmental
changes. If it is raining, too windy or too cold, the
smart irrigation control sprinklers will automatically shut off.

Check with your local water agency for available rebates on irrigation controllers and smart timers. • Aim your sprinklers at your lawn, not the sidewalk – By simply adjusting the direction of your sprinklers
you can save water, prevent water pollution from
runoff, keep your lawn healthy and save money.
• Set a timer for your sprinklers – lawns absorb
the water they need to stay healthy within a few
minutes of turning on the sprinklers. Time your
sprinklers; when water begins running off your
lawn, you can turn them off. Your timer can be set
to water your lawn for this duration every time.
• Water at Sunrise – Watering early in the morning
will reduce water loss due to evaporation.

Additionally, winds tend to die down in the early
morning so the water will get to the lawn as
intended.
• Water by hand – Instead of using sprinklers,
consider watering your yard by hand. Handwatering ensures that all plants get the proper amount of water and you will prevent any water
runoff, which wastes water and carries pollutants
into our waterways.
• Fix leaks - Nationwide, households waste one
trillion gallons of water a year to leaks – that is
enough water to serve the entire state of Texas for
a year. If your garden hose is leaking, replace the
nylon or rubber hose washer and ensure a tight
connection. Fix broken sprinklers immediately.

Page 1606 of 2028 ends

Do your part to prevent water
pollution in our creeks, rivers, bays
and ocean.

Clean beaches and healthy creeks, rivers,
bays, and ocean are important to Orange
County. However, many common household
activities can lead to
water pollution if you’re
not careful.

Litter, oil, chemicals and
other substances that
are left on your yard or
driveway can be blown
or washed into storm
drains that flow to the
ocean. Over-watering
your lawn and washing
your car can also flush
materials into the storm
drains. Unlike water in sanitary sewers
(from sinks and toilets), water in storm
drains is not treated.

You would never pour soap, fertilizers or oil
into the ocean, so don’t let them enter
streets, gutters or storm drains. Follow the
easy tips in this brochure to help prevent
water pollution. GENUINE

RECYCLED
P APER
50% PRE-CONSUMER
AND
15% POST-CONSUMER

REMEMBER THE

WATER IN YOUR

STORM DRAIN

IS NOT TREATED
BEFORE

IT ENTERS OUR

WATERWAYS
The Ocean Begins at Your Front Door
For more information,
please call the
Orange County Stormwater Program
at 1-877-89-SPILL (1-877-897-7455)
or visit
www.ocwatersheds.com
To report a spill,
call the
Orange County 24-Hour
Water Pollution Problem
Reporting Hotline
1-877-89-SPILL (1-877-897-7455).

For emergencies, dial 911.

The tips contained in this brochure provide useful
information to help prevent water pollution while
performing everyday household activities. If you
have other suggestions, please contact your city’s
stormwater representatives or call the Orange
County Stormwater Program.

Help Prevent Ocean Pollution:

Household Tips

Page 1607 of 2028 ends

Gardening Activities
� Follow directions on pesticides and
fertilizers, (measure, do not estimate
amounts) and do not use if rain is
predicted within 48 hours.
� Water your lawn and garden by hand to
control the amount of water you use. Set
irrigation systems to reflect seasonal
water needs. If water flows off your yard
and onto your driveway or sidewalk,
your system is over-watering.
� Mulch clippings or leave them on the
lawn. If necessary, dispose in a green
waste container.
� Cultivate your garden often to control
weeds.

Washing and Maintaining Your Car
� Take your car to a commercial car wash
whenever possible.
� Choose soaps, cleaners, or detergents
labeled “non-toxic,” “phosphate free” or
“biodegradable.” Vegetable and citrusbased products are typically safest for the environment, but even these should
not be allowed into the storm drain.
� Shake floor mats into a trash can or
vacuum to clean.
� Do not use acid-based wheel cleaners and
“hose off” engine degreasers at home.

They can be used at a commercial facility,
which can properly process the washwater.
� Do not dump washwater onto your
driveway, sidewalk, street, gutter or
storm drain. Excess washwater should
be disposed of in the sanitary sewers
(through a sink, or toilet) or onto an
absorbent surface like your lawn.
� Use a nozzle to turn off water when not
actively washing down automobile.
� Monitor vehicles for leaks and place
pans under leaks. Keep your car well
maintained to stop and prevent leaks.
� Use cat litter or other absorbents and
sweep to remove any materials deposited
by vehicles. Contain sweepings and
dispose of at a HHWCC.
� Perform automobile repair and
maintenance under a covered area and
use drip pans or plastic sheeting to keep
spills and waste material from reaching
storm drains.
� Never pour oil or antifreeze in the
street, gutter or storm drains.

Recycle these substances at a service
station, HHWCC, or used oil recycling
center. For the nearest Used Oil
Collection Center call 1-800-CLEANUP
or visit www.ciwmb.ca.gov/UsedOil.

Pollution Prevention
Household Activities
� Do not rinse spills with water! Sweep
outdoor spills and dispose of in the trash.

For wet spills like oil, apply cat litter or
another absorbent material, then sweep
and bring to a household hazardous waste
collection center (HHWCC).
� Securely cover trash cans.
� Take household hazardous waste to a household hazardous waste collection center. � Store household hazardous waste in closed,
labeled containers inside or under a cover.
� Do not hose down your driveway, sidewalk or
patio. Sweep up debris and dispose of in trash.
� Always pick up after your pet. Flush waste
down the toilet or dispose of in the trash.
� Bathe pets indoors or have them
professionally groomed.

Household Hazardous Wastes include:
� Batteries
� Paint thinners, paint strippers and removers
� Adhesives
� Drain openers
� Oven cleaners
� Wood and metal cleaners and polishes
� Herbicides and pesticides
� Fungicides/wood preservatives
� Automotive fluids and products
� Grease and rust solvents
� Thermometers and other products
containing mercury
� Fluorescent lamps
� Cathode ray tubes, e.g. TVs, computer
monitors
� Pool and spa chemicals
For locations and hours of Household Hazardous Waste Collection Centers in Anaheim, Huntington Beach, Irvine and San Juan Capistrano, call (714)834-6752 or visit www.oclandfills.com. Page 1608 of 2028 Clean beaches and healthy
creeks, rivers, bays and
ocean are important
to Orange County. However,
many common activities such as
pest control can lead to water
pollution if you’re not careful.

Pesticide treatments must be
planned and applied properly
to ensure that pesticides do
not enter the street, gutter or
storm drain. Unlike water in
sanitary sewers (from sinks and
toilets), water in storm drains is
not treated before entering our
waterways.

You would never dump pesticides
into the ocean, so don’t let it
enter the storm drains. Pesticides
can cause significant damage
to our environment if used
improperly. If you are thinking
of using a pesticide to control a
pest, there are some important
things to consider.

For more information,
please call
University of California Cooperative
Extension Master Gardeners at
(714) 708-1646
or visit these Web sites:
www.uccemg.org
www.ipm.ucdavis.edu
For instructions on collecting a specimen
sample visit the Orange County
Agriculture Commissioner’s website at:
http://www.ocagcomm.com/ser_lab.asp
To report a spill, call the
Orange County 24-Hour
Water Pollution Problem
Reporting Hotline
at 1-877-89-SPILL (1-877-897-7455).

For emergencies, dial 911.

Information From:

Cheryl Wilen, Area IPM Advisor; Darren Haver,
Watershed Management Advisor; Mary
Louise Flint, IPM Education and Publication
Director; Pamela M. Geisel, Environmental
Horticulture Advisor; Carolyn L. Unruh,
University of California Cooperative
Extension staff writer. Photos courtesy of
the UC Statewide IPM Program and
Darren Haver.

Funding for this brochure has been provided in full
or in part through an agreement with the State Water
Resources Control Board (SWRCB) pursuant to the
Costa-Machado Water Act of 2000 (Prop. 13).

Help Prevent Ocean Pollution:

The Ocean Begins
at Your Front Door
Responsible
Pest Control

Page 1609 of 2028 ends

Yorba Linda City CouncilFebruary 3, 2026

Yorba Linda City Council
February 3, 2026